Diseases of garden plants
Flowers - Annuals
Flowers - Perennials
Native Plant gardening
Flowers - Perennials
|Can I cut back the green leaves of my irises since they have already bloomed? They are crowding other plants nearby. Dolores, Mt. Washington|
|Hello, Dolores in Kentucky: Iris provide wonderful color in the spring garden. This large genus has hundreds of species ranging in color as well as size. As with all plants, just because they have finished blooming does not mean it is time to cut back the foliage. In fact, this can jeopardize next season’s flowers. It is important to leave the foliage alone so it can collect the nutrients it needs to remain healthy and flower again for you year after year. Iris benefit from being divided every few years. They spread and become overcrowded, forcing them to compete for nutrients, and as a result we get fewer blooms. So if you have not divided them recently, you can put this on your list of garden chores for late winter or early spring as soon as the soil can be worked. If you must divide them now go ahead and cut back the foliage, dig them up, and replant them but keep in mind that you may not get any blooms next spring. It could take them a couple seasons to produce flowers again. If you can wait until later this winter or early next spring just as the foliage begins to emerge, that would be ideal.
|How can I take care of an outdoor lamb's ear plant? Glenda, Glasgow|
|Hello, Glenda: The most common lamb’s ears (Stachys byzantina) are silvery-blue in color and the foliage is very soft, almost velvety, to the touch. Most of the Stachys are low-growing, spreading perennials. They are wonderful groundcovers and when combined with other plantings add a different color and texture to the garden. Lamb’s ears can be finicky when it comes to planting site and drainage. They require full to part sun and excellent drainage. With the clay soil that we as Kentucky gardeners are dealing with, drainage can be an issue. If the soil is compacted, amending it with an expanded slate material such as Permatill will help to break up the clay and improve drainage. Rot can be a problem during our hot, humid summer months. Excessive rainfall can also make these plants look ratty but just cut back any withered foliage. These herbaceous perennials do not require much in terms of fertilization. They are drought-resistant once established and produce lavender spikes in the late spring to the summer months.|
|How can you kill out Japanese anemone in an established perennial bed? It ends up taking over before summer's end! Am I going to have to start all over and kill out everything? Christee, Paris|
|Hello, Christee: The good news is that you certainly do not have to start all over again. Some perennials spread more than others and Japanese anemone, once they become established, can spread rapidly. Japanese anemone species hupehensis, tomentosa, as well as the hybrids, are herbaceous perennials that really put on a show in the fall garden. They can reach up to 5 feet tall and 3 feet across. They are available in single, semi-double, and double blooms ranging in color from white to lilac. These fibrous-rooted perennials can be thinned out so they do not take over the garden. Spring is a good time to do this so as soon as you see the foliage coming up in your garden, get out the hand trowel and start dividing. This will keep them in check and free up space needed for your other perennials. Share your divisions with your gardening friends or donate them to your county Master Gardener program. They will likely have a spring plant sale and will be happy to take them off your hands. If you find that later on in the season you did not remove enough, you can always take more out. It will likely be harder to dig out and may not transplant well at this time of year, but for your purpose it will get the job done.|
|I am removing two overgrown large boxwood shrubs that have gotten too tall in front of my house. I would like to replace with low-growing perennials. The space is 9 feet long and I don't want anything over 18 inches tall. Do you have any suggestions? Pamela, Grayson|
|Hello, Pamela: There are a few things to consider when it comes to choosing your new plants. Most important is the amount of sunlight that space receives. Six hours of direct sun is considered full sun. Less than three is considered shade, and anything in between is part sun. Not knowing how much light your space gets I will give you options for both. Sun-loving perennials that do not get more than 18” tall would be dianthus, geraniums, creeping phlox, and Veronica ‘Georgia Blue.’ These all have different bloom colors so if you have specific requests let me know and I can give you more details. Shade-loving options would be ferns, heuchera, tiarella, Hakone grass, hosta, and rumex. Some varieties of ferns and hosta will grow larger but for the most part they are lower growing perennials. You may just want to wander around your favorite garden center to see what catches your eye. Let me know if you need further suggestions.
|I bought a hollyhock plant and woke up this morning to water it and found that it had been either chewed or stepped on and was broken. Can it be saved? The roots are still in the ground: will another plant emerge from the root that remained in the ground? I was so brokenhearted to see this. Kari, Chester|
|Hello, Kari in Pennsylvania: It is disappointing when we look forward to watching our perennials bloom only to find them chewed off or damaged before their time to flower arrives. Unfortunately, if the stems are completely broken there is no way for the plant to transfer moisture and nutrients needed for growth. Were all of the stems broken? If so go ahead and get your pruners out; cut back the foliage right below where it was damaged. The roots were not affected so the plant will attempt to put on new growth in an effort to survive. Make sure the roots are not allowed to dry out and you can feed with a well-balanced fertilizer such as 10-10-10. This will help to promote new growth. The good news is that we still have plenty of warm weather left before winter arrives and this means your hollyhock can produce new growth and potentially flower this season, but more importantly store up energy for next year's flowers. The plant is stressed so make sure the soil stays consistently moist and that it is planted in full sun. You might consider protecting it if you think a critter maybe chewed on it. Visit your local garden center to see what they carry in terms of deterrents and physical barriers.|
|I bought a home with several montauk daisy plants last fall. They bloomed in the fall, but they were floppy and fell from the weight. I pruned them low in December. I read that to prevent flopping, I should prune again in May. But there are some buds already on the branches. Should I prune now to prevent flopping in the fall? Or will cutting off the buds prevent flowering? Someone told me that if there are buds on it already, it will flower in the spring. Lauren, Louisville|
|Hi, Lauren in Kentucky: Montauk daisies (Nipponanthemum nipponicum) are a perennial favorite among many gardeners as well as butterflies. Planted in mass, they provide a lovely show in the fall. They thrive when grown in full sun and nutrient-rich, well-drained soil. Other than pruning they are considered a low-maintenance plant. If not properly pruned they become leggy and flop over in the fall when they are suppose to be in their prime. Like you mentioned, they should be cut back in the early spring to prevent them from flopping over later in the growing season. Go ahead and cut them back approximately one-third to one-half of their size. This will encourage your perennials to become fuller, more compact, and less leggy. It may seem drastic to remove some flower buds but they will certainly produce more and you will have a more attractive plant in the long run. These fall bloomers are best left alone to collect food and nutrients for next year's flowers so do as you did last year and wait until later in the winter to prune. You can protect them with a thin layer of mulch during the winter months.|
|I bought large 2' black-eyed Susan because people have been stealing my plants. I kept it inside longer than I should have. I put it out this week, but now I hear we may get snow. Should I dig it up, pot it, and try the basement? Jean, Akron, OH Jean, Akron|
|Hi Jean: Hopefully the people who are helping themselves to your flowers will be less likely to do so if you plant them in the ground. Black-eyed Susans belong to the Rudbeckia genus. Within this genus there are more than 20 species but most of the them are hardy to at least zone 4, which means that you can grow them as a perennial. They will be happier growing outdoors year-round and as long as they receive good light they will provide you with plenty of blooms. We don't want to plant perennials too late in the fall so get them in the ground as son as possible. Choose a space in your garden where these plants can naturalize and dig the holes twice as wide and just as deep as the containers they are growing in. Backfill with compost or the existing soil. Be sure to add a thin layer of mulch to help insulate the roots during the winter. Black-eyed Susan flowers attract birds and butterflies but hopefully not sticky fingers!|
|I have a Dinner Plate hibiscus and it has brown spots on the leaves. I repotted it into a larger pot and put rocks in the bottom for better drainage, and now it is getting new leaves on the lower half of the stems, but only a few from about 4-6 inches from the bottom up. Can I cut back the stems to an inch or two above where the new leaves basically stop and have it bush out better, or do I need to leave it alone and let nature take its course? I have it potted as I live in an apartment and I want to be able to take it with me when we move.
|Hello, Michelle in Florida: Hibiscus moschueutos, commonly referred to as a hardy or Dinner Plate hibiscus, produce very large blooms that give even a northern garden a tropical feel. Here in Kentucky we have to prune these plants back later in the fall, and the following spring they put on new growth. Since you are gardening in Florida I would suspect that you only prune to maintain size. The best time to prune hibiscus in warmer zones is during the late spring/early summer. A general rule for pruning shrubs is to not take off more than one-third of the plant each year. If you need to prune more than that it should be done year after year. In your case it sounds like you may just need to remove the foliage that does not look good and let it put on new growth to replace the lost. As long as the overall health of the plant is good, removing the spotty foliage should be all you need to do at this point. If you have seen insect activity or anything unusual about your hibiscus, you can take a sample to your County Cooperative Extension Office for the horticulture agent to look at. Otherwise make sure that the container has a drainage hole and that it is not blocked. Hibiscus thrive in full sun (six hours or more each day) and consistently moist but well-drained, fertile soil. You can feed your plant with a well-balanced plant food such as 10-10-10 once a month.|
|I have a huge Lord Baltimore hibiscus I need to move. Is it toxic to horses? My 32-year-old Arab will try to munch anything he can reach! Lisa, Hamilton|
|Hello, Lisa: Lord Baltimore hibiscus, commonly known as Rose Mallow, produces dinner plate-size blooms that are crimson red in color. They are prolific bloomers and can reach upwards of 5 feet tall with their burgundy stems. Hibiscus moscheutos ‘Lord Baltimore’ belongs to the Malvaceae family. According to the ASPCA/Animal Poison Control Center, some members of this family are poisonous to horses. The only one that is listed is Hibiscus syriacus, commonly known as Rose-of-Sharon. It does not list any Hibiscus moscheutos species as toxic to horses. You should contact your veterinarian to be certain. If you do end up moving your perennial hibiscus make sure to move it to a sunny location. When transplanting, it is always best to dig the new hole before digging up the existing plant so that it is less stressful on the plant. Try to keep as much of the root system attached as possible and keep the hibiscus watered well for the first couple of months. You will want to treat it like a new addition to the garden.|
|I have a sunny flower bed and I want to plant perennials with lots of color, but I can't seem to get a combination of plants to let me have color from April to August. I have daffodils that popped up in late February and are finished now. I have peonies that are up and I am guessing will bloom in three or four weeks. I have two butterfly bushes that I know will last through a big part of summer, and I have yellow coriopsis in front of those that will be good in the middle of summer too. But I don't have much that will be in bloom in late April, May, and early June. Can you make recommendations for what I could add to the bed (it is in sun most of the day) that would give me color at the time I am missing?
Gail Gail, Lexington|
|Hello, Gail in Kentucky: A well-landscaped perennial garden will provide interest during at least three seasons of the year, if not all four. The trick is planting perennials that will bloom at different times of the growing season. In general, perennials have a bloom time of about three weeks. Some are better bloomers than others but none provide as much color as an annual would. You might consider planting a few annuals among the perennial garden so that your space is never lacking in color. As far as sun-loving perennials that will bloom for you in April, May, and early June, there are too many to rattle off but here are a few suggestions: amsonia, which has a blue bloom early in the spring with stunning fall color. Baptisia is also a spring bloomer and available in purple and yellow. Dianthus is a low-growing grass-like perennial available in assorted colors. Hardy geraniums are great bloomers and typically come in purple or pink. Echinacea will provide blooms for a good part of the summer and are available in an array of color options. Pervoskia or Russian sage is a must-have in a sun-loving perennial garden. It blooms most of the summer, and is left up in the winter as its silvery foliage provides nice structure in the winter garden. Shasta daisies are good bloomers and nice for cut flower arrangements. These are just a few options but you should visit your local garden center to see what they have available. A knowledgeable staff member should be able to give you specifics in terms of bloom times. For a more detailed list of sun-loving perennials for Kentucky gardeners you can visit www.ca.uky.edu/agc/pubs/ho/ho76/ho76.htm
. This publication also has detailed information on bloom times.|
|I have blue iris in pots. The leaves are turning brown, but they are still blooming. Should I cut the fading leaves? What fertilizer should I use? Joyce H., Cadiz|
|Hi Joyce: Iris is a large genus with many species and even more varieties and cultivars. Bearded, Japanese, and Siberian irises are all grown from rhizomes but there are bulbous irises as well, so I am not sure which one you are growing. Regardless, it is concerning that the foliage is turning brown. At this time of the season the foliage should be green and lush no matter which iris you are growing. It is important for the foliage to remain healthy and green to collect nutrients for next year's flowers. Do the containers provide good drainage? Depending on the specific plant you are growing, they may be water lovers or prefer well-drained soil. It would be helpful to know which iris you are growing but in general, a well-composted manure or a 5-10-5 fertilizer will be beneficial to your plant. Before feeding you might want to make sure the rhizomes/bulbs are still firm. If they are soft and have a foul smell it is not worth feeding them. You will want to remove all brown foliage and inspect for any insect activity. Cadiz, KY|
|I have daylilies in my flower bed. They bloomed beautifully. Now that the blooms are drying, how do I dead-head? Is there anything I can do to extend the bloom season? Debbie, Alexandria|
|Hello, Debbie: Daylilies (Hemerocallis) are an old-fashioned favorite. Ditch lilies, as they are called in the trade, are in full bloom right now (mid-late June). Of course there are now many hybrids to choose from and like all perennials, daylilies have their bloom time, typically a three-week period in early summer. There are some varieties that are better re-bloomers than others. ‘Happy Returns’ is probably the most common re-bloomer. Certainly cutting back faded blooms will encourage more to come on. Use your gardening scissors or pruners and take back the flower and stem all the way to the base of the plant. Each stem will only produce one set of flowers each season so after the blooms have faded go ahead and remove them. Daylilies will bloom best when given optimal growing conditions; for these perennials this means they should be planted in full to part sun with nutrient-rich soil. Each spring it is a good idea to side dress the soil with organic matter or apply a fertilizer lower in nitrogen and higher in phosphorus and potassium. If your lilies are established and have been in the ground for three to five years they will benefit from being divided. Over-crowded plants do not bloom well.
|I have tall phlox that started out looking healthy; as they progressed the leaves have turned yellow with green and did not bloom. The ones at the front of the house did just fine, they have kept their green color and bloomed beautifully. Do you have a suggestion as to my problem? Gloria, Sault Ste. Marie|
|Hello, Gloria: Tall garden Phlox (Phlox paniculata hybrids) is a wonderful addition to any sun-loving, perennial garden. When they are planted in ideal conditions, they are prolific summer bloomers. As with any new addition to the garden, it may take a year for the plant to become established. If you just planted them this spring and the ones growing up front are not given the best growing conditions, it may be that they are using their energy to establish roots instead of the flowers. Are your phlox receiving the same amount of sunlight? The more sun the better when it comes to this perennial. What about the drainage? Does the area in the back of the house drain as well as the front? If not, the plant may be suffering from root rot and if you have had as much rain as we have had this summer, in combination with poor drainage this could certainly be the problem. Yellowing foliage can also be an indication of nutrient deficiency; both iron and nitrogen deficiencies can result in chlorotic foliage. This is most common in soils with a high pH. You can have your soil tested to make sure this is not the problem. The most common problem we see with phlox is powdery mildew, but from what you have described it does not sound like this is the problem with your phlox. The foliage would have more of a white cast to it than a yellow one if this were the case. You can take a sample of your phlox to a local garden center with a knowledgeable staff and they will be able to look at your sample and give you a more definitive answer.|
|I have two Snow Hill salvias in my front yard. They are exposed to full sun. This is my second year of having them. My question is, is it natural for them to lie down almost flat? They look more like a life preserver wrapped in white. What can I do, if anything, to correct this? Robert H., Union Furnace|
|Hello, Robert in Ohio: Salvia x sylvestris ‘Snow Hill’ is an herbaceous perennial that provides pure white, spike-like flowers in the sun-loving garden. A favorite among bees and butterflies, it has a compact growth habit usually reaching about 20 inches tall each growing season. It is not common for this plant to flop or become leggy simply because it has a compact growth habit, but if it is growing in a moist soil that does not drain well or exposed to extreme humid conditions it can cause the salvia to flop over. This salvia prefers to grow in well-drained soils and will tolerate drought conditions. Another possibility is an animal lying down in the plants. These perennials in general are considered low-maintenance and do not have many insect or disease problems. It sounds like your plants are receiving sufficient sunlight so this should not be an issue. At this point staking or pruning may be necessary to keep the plants upright. Visit your local garden center to see what they carry in terms of stakes, or get your pruners out and cut all the way back to where the new foliage has emerged. It is still very early in the growing season so pruning may be your best option at this point. Removing spent blooms will encourage this salvia to continue blooming.|
|I live in Kentucky and want to plant perennials that will come up every year, but don't want hybrids because so many times they didn't come back the next year. I hear that hybirds are unreliable. What are some great perennials I could plant in my garden with sucess? Sharma, Catlettsburg|
|Hello, Sharma: A hybrid is a cross between two parent plants. This happens both naturally and with the help of humans. When we create hybrids, the parents are intentionally picked because of their admirable characteristics, and then one plant is created that has good attributes from each parent. The hybrid perennials that you will find in any reputable garden center are there because they are reliable, disease-resistant plants. Although these hybrids may not come true to seed, they are still well worth planting in the garden. There are many reasons for plant failure but I would not suspect that the reason for plant failure is due to it being a hybrid. Choosing the right plant for the right space is essential in being a successful gardener. You will want to consider the available sunlight, soil conditions, and preferences that you have in terms of color, height, etc. If you give me more details of your garden I will be happy to give you specific suggestions. For now visit www.ca.uky.edu/agc/pubs/ho/ho76/ho76.htm
. These links are publications from the Kentucky Cooperative Extension Service in collaboration with research universities that have detailed lists of perennials that are all good choices for perennial gardens here in Kentucky. The list includes both hybrids and species.|
|I live in Lexington, KY. This is my second year planting flowers in my front yard. I was successful last year and would like to attempt it again. Last year, I planted them in mid-May. I am anxious to plant them now. Is it too early? I would like to plant perennials. Jennifer, Lexington|
|Hello, Jennifer in Kentucky: Gardening is certainly addictive and it sounds like you have caught the bug! All plant material has ideal planting times, and in Kentucky perennials can be planted throughout the spring, summer, and early fall. The only time we want to avoid planting them is late fall and winter. This is due to the potential of the soil freezing and thawing, which results in heaving of roots that are not yet established, making them susceptible to winter damage. When we plant the other times of the year they have enough time to get their roots settled before the cold weather arrives. There are benefits to planting in the spring since the temperatures are typically cooler and rainfall is common. This is helpful in terms of good conditions for the plants to get established. We will likely have to water more during the hot summer months if this is when we do our planting. So, certain times of the year it is less maintenance on our part if Mother Nature cooperates. No matter when you decide to plant, it is always important to choose plant material that will be happy growing in conditions that you can provide. Sunlight, soil, and nutrients all need to be taken into consideration when designing your garden. If you have not had your soil tested, you may want to so you know what nutrient levels you are dealing with. You can contact your County Cooperative Extension Service for details on having your soil tested. Happy planting!|
|I live in Monticello, Kentucky. I have a groundcover plant I would like to have identified. It has green oval leaves that are silvery white on the underneath. It blooms white flowers on a 6-8" stem in the spring. The green leaves are about 1-1/2" long. Can you help me out? Sue, West Chester|
|Hello, Sue: For a positive identification I would like to see a picture of your groundcover. You are welcome to send a photo to my e-mail at firstname.lastname@example.org. Without seeing a picture I can only speculate what you have growing in your garden. My first thoughts were possibly Tiarella, Lamium (Dead nettle), or pachysandra but none of these fit your exact description. Is this plant growing in the sun or the shade? Does the foliage have smooth edges or are they scalloped or toothed? When it blooms is it a single flower or one stem with multiple flowers on each stem? All of these answers will help me determine what you have but a picture would be even better. Sorry I don’t have an answer for you yet.|
|I live in northern Kentucky, zip code 41008. When can I cut my rose bush back? Sally, Carrollton|
|Hello, Sally in Kentucky: The best time to prune your rose is during the late winter/early spring months before the new growth begins. During this time your rose will be dormant, which makes it less susceptible to winter injury and other potential problems. This is especially true if you are pruning to control the size. As a general rule, it is best not to remove more than one-third of the size of the rose at one time. If you need to drastically reduce the size of your rose, it is a good idea to take off one-third each year and then do this year after year to maintain the size you want. When it is time to prune be sure to use a clean, sharp, and rust-free pair of pruners. Make your cuts flush to the nearest intersecting branch so there are no stubs. If your reason for pruning is to remove dead/diseased or crossing canes, go ahead and get your pruners out now. Good sanitation practices are always important in terms of the health of our plants so be sure to clean up all plant debris after you prune. Leaving it provides a wonderful environment for insects/diseases to thrive.|
|I live in southeast Wisconsin. I need to dig up several hostas and store the rhizomes until spring. Construction will destroy all of them if not dug up and stored. Can I dig them, dry them, and store them in peat until spring? Then should I soak them in water for a time before planting? I am hoping to save them all, approximately 50-60 mature, large, blooming plants. Jean, Genessee Depot, WI
Jean, Genesee Depot|
|Hi Jean: This sounds like a big job but if you want to save your hostas they will certainly need to be moved before construction begins. Your best option is to dig up the perennials, keeping the fleshy roots and spreading rhizomes intact. Keeping the moist soil around the roots is important in terms of reducing stress during this transition. If you have a space in the garden that is not going to be disturbed during construction this would be ideal as a temporary home for your plants. Given the number you are dealing with you have a couple of options, you can either put them back in the ground or purchase inexpensive nursery containers and pot them up. Visit your local garden centers and see if they save or recycle their nursery containers and if you're lucky they may give them to you. Hostas are hardy to USDA zone 3 so they are very cold tolerant but they will still need to be protected from the harsh winter weather. Place the containers on the north side of your home if possible and snuggle them close together. Use straw bales, bags of mulch, or even bags of soil between them. You will want to water them immediately after they are dug up but rain and snow should be sufficient moisture during the winter months. Cut back the foliage as you normally would after the first killing frost and then add a couple inches of mulch to the top of each container to help retain warmth and moisture. Depending on what Mother Nature brings this winter you may have some loss but one or two is better than 50-60!|
|I planted two perennial false spirea plants in my front yard that is mostly shady. I have watered them, used Miracle Gro and Root Plus spring, summer, and fall but they aren't doing well. The leaves get dry and brown, the flowers don't turn pink or purple, and dry out and wilt. I have pruned them back in the fall two years in the row and in the spring, new leaves have sprouted and it begins to get full and really look nice, but then near the end of summer they dry out again and look terrible. My neighbor who also lives on the same side of the street as I live on said she didn't have any luck with the false spirea and they dried out for her and she pulled them out of the ground. The only thing that has really grown well for me with little maintenance is the azalea plant bush. Should I dig up the false spirea and plant something else like an azalea? Evelyn, Maple Heights|
|Hi Evelyn: Astilbe, or false spirea as it is sometimes called, is a shade-loving perennial that will bloom best if given morning sun. The foliage will burn if the plant is not given sufficient moisture, especially if exposed to hot afternoon sun. Astilbe prefers a nutrient-rich, moist soil. From what you have described, and the fact that these perennials are not prone to insect or disease issues, I suspect the issue may be insufficient moisture. Keep this in mind for next growing season and if it is still not happy then you might consider transplanting it to another part of the garden. Bloom color will depend on variety and the color will not change according to soil acidity. For now, cut back the foliage after the first hard freeze and add a thin layer of mulch. Next spring, side dress with compost and keep it well-watered and hopefully it will be a happier plant. Otherwise some shade-loving shrub options include: aucuba, mahonia, pieris japonica, hydrangea, taxus, boxwood, or more azaleas. There are many other shade-loving perennials to choose from as well: ferns and hostas are the most common but heuchera, tiarella, hellebore, Chinese wild ginger, columbine, epimedium, plumbago, acanthus, and spigelia are also interesting options.|
|I purchased two mature foxglove plants. I put them in the ground and the leaves seem wilted, althought the flowers look great. Why are the leaves wilting? The soil seems to be good, not too wet or dry. Also, after the stalk blooms and the flowers are done, I cut on the stalk and hope more produce over throught the summer, assuming the plant makes it. Any other suggestions would be great.
|Hello, Theresa: I am sure the foxglove (digitalis) was beautiful when you purchased it. It likely has done some traveling before it ended up in your garden. If the garden center where you bought your plant does not grow their own, this plant probably has some miles under it. When we move plants from one environment to the next, there is always a certain amount of transplant stress involved. It is important to give these new additions extra attention until the roots have had time to take hold and establish. Since the plant is in bloom, it is using most of its energy on the flowers and not on the roots. You might consider cutting the flowers and enjoying them in a vase so the energy can be concentrated on root development. This will make for a happier/healthier plant in the long run. Yes, in the future when the flowers have faded you should cut the flower stalk back and this will encourage more blooms throughout the spring and early summer months. As with any new addition to the garden, we are responsible for making sure it has the right growing conditions. Foxglove should be planted in a space where it will receive part sun and moist but well-drained soil. I would suspect that since the foliage is wilting it is in need of additional moisture. Water the base of the plants so the roots receive the moisture as opposed to the foliage. It is better to water deeply and less often than to water shallow and more often. Avoid fertilizing for the first year. It is best to let the perennial become established in the environment that occurs naturally.|
|I read in your magazine about amsonia and want to know where this may be purchased? Paula, Clarkson|
|Hello, Paula: Thanks for reading the Kentucky Living magazine! Amsonia is a must-have perennial for any sun-loving garden. It has a very light and airy characteristic to it and puts on a stunning show later in the fall. As far as locating this plant, it should be available at your local garden centers and/or nurseries later in the spring. I would not expect to find it at a Home Depot or Lowes. You may start calling around to see who carries it locally and ask them to call you when they receive their shipment. If you need help finding sources, contact your County Cooperative Extension Service. The Grayson County horticulture/agriculture agent can be reached at (270) 259-3492. If you cannot find it in your county, we at The Plant Kingdom in Louisville consider it one of our favorites and try to always have a good supply. Let us know if you need us to hold one for you. Our phone number is (502) 893-7333.|
|I'd like some information on growing Joe-Pye Weed in the home garden for butterflies. I hear there are some very nice new plants available. Rosie, Lebanon|
|Hi, Rosie: There are many species of Joe-Pye Weed (Eupatorium) and even more cultivars. All belonging to the aster family, these herbaceous perennials are happiest growing in full sun to part shade and require moist soils. They should not be allowed to dry out between waterings. A favorite among butterflies, these clump-forming perennials can reach anywhere from 2-10 feet tall and 2-3 feet wide, depending on variety. They are not susceptible to any serious insect or disease problems but leaf scorch can occur during hot and dry periods. Depending on the species, Eupatoriums are native from the eastern and northern United States all the way to Asia. Again depending on variety they produce either dark/light pink or white blooms from July through September and the seed heads provide winter interest. This perennial can be used in fresh cut or dried floral arrangements. Not to get too technical with the species for this purpose, we can concentrate on the cultivars that are commercially grown and available for home gardeners. ‘Little Joe’ is a dwarf variety reaching 3-4 feet tall with lavender blooms. ‘Pink Frost’ is a variegated variety with pink blooms, and ‘Atropurpureum’ has purple stems, foliage, and flowers. ‘Album’ and new this year ‘Ivory Towers’ are both white bloomers. Check with your local garden center to see what they carry, or Plant Delights Nursery online is a reliable source for mail order; they typically have some unusual ones.|
|My cat likes to eat my dianthus flowers--will it make her sick? Cynthia, Saint Albans|
|Hi, Cynthia: I will start by saying that I am not a veterinarian, but as a gardener I can tell you that some plants or parts of plants are more dangerous than others when it comes to toxicity. Certain plants are more harmful than others depending on the animal in question. The list of toxic plants available from the Animal Poison Control Center and the ASPCA does list Dianthus caryophyllus as a plant that is toxic to cats. As far as the parts of a plant that are toxic, we know that the seed is as well as the foliage if consumed in large amounts. Animals have a good sense about them and usually stay away from plant material that could potentially be harmful to them, but just to be safe you should contact your veterinarian.|
|My climbing rose is 3 years old and struggling. It had three branches this spring and one gave me a nice rose. Shortly after, it started to drop all the leaves. It has some live growth at the bottom but now the other branches look like they are dying. Should I cut off the three branches? What can I do to help my rose bush? Mary, Kenmore|
|Hi, Mary: Your climbing rose does not sound like it is very vigorous with little growth and few flowers. First, let’s make sure it is growing in the right conditions. Climbing roses should receive a minimum of six hours of direct sunlight each day. Ideally it should get eight or more but six will do. Roses do well in nutrient-rich, well-drained soil. If your climbing rose is planted in new construction with poor drainage or has not been given additional nutrients for three years, this may be part of the issue. As far as the three canes that do not look good, go ahead and remove them. It is fine to prune back dead or diseased canes anytime of the year. Other pruning should wait until the plant is dormant. Since the new growth looks healthy, let's encourage this to be the new climbing rose and hopefully it thrives. It will benefit from being fed if you have not done so recently. Always follow application rates with the fertilizer you choose. Too much can have the reverse effect in terms of flowers. You can take a sample of one of the canes that you remove to your horticulture agent with your County Cooperative Extension Service or to a garden center with a knowledgeable staff to find out why they declined.|
|My Easter lilies have nice folage but no blooms for several years now. Any thoughts? Doris, Frenchburg|
|Hello, Doris: Lilium longiflorum are commonly known as Easter lilies or white trumpet lilies. These herbaceous perennials are found in abundance this time of year. They are forced into bloom for the Easter season. In the garden they are mid-summer bloomers. There are many cultivars, some even blooming pink, yellow, or cream. ‘Nellie White’ is a cultivar that is sweetly scented and cottony white in color, typically grown in containers for Easter. In the garden, these perennials should be planted in a space where the soil is well-drained and the plant will receive full sun. If the lily does not get at least four to six hours of sun, it may not bloom. You might consider transplanting them to a sunnier location if you think this might be an issue. Have you fertilized at all? If not, you can go ahead and feed with either a water-soluble or a slow-release fertilizer. An all-purpose fertilizer is fine or a ratio of 5-10-5 will also be beneficial. Make sure to apply recommended amounts since over-fertilizing can cause our plants not to bloom. It sounds like your plants are happy, they just need to be encouraged to bloom.|
|My irises either bloom sparsely or not at all. I have divided them but only get a lot of leaves. I have them in different gardens and only the ones by my mailbox bloom but only a few every year. In late summer the leaves start to turn brown or yellow so I cut them back. Any advice would be welcome. Sheila, Cortland, NY Sheila, Cortland|
|Hi Sheila: Iris are an old-fashioned favorite and this large genus has hundreds of species and even more cultivars, but the Bearded, Siberian, and Japanese are the most common. You mentioned that you divided your iris and if these were older, crowded plants, this would explain the lack of blooms before they were divided. Iris like to be divided every few years; they spread and become overcrowded, forcing them to compete for nutrients, and as a result we get fewer blooms. After the iris have been divided, it could take them a couple seasons to produce flowers again. It is important that they spend their energy on establishing their roots before they use it to produce flowers. This ensures a healthy, long-lived plant. Provided that your iris are receiving enough sunlight and nutrients they will eventually bloom again. Be careful not to fertilize too much since too much nitrogen can promote leafy growth instead of flowers; a 5-10-5 fertilizer is a good ratio for iris. Leaving the foliage up until it turns brown or yellow in the fall is important so it can collect nutrients for future blooms.|
|My mother was interested in trying to find a nursery in Louisville, KY, that carries a plant names amsonia. Can you help? Bridget, Louisville|
|Hi, Bridget: Let your mother know she is in luck--The Plant Kingdom in Louisville has amsonia in stock. We have them available in both quart and gallon size containers. They are just coming up in the garden so they are not large plants at this point, but will certainly grow as the season continues. We are located at 4101 Westport Road in St. Matthews. The phone number is (502) 893-7333. We are open Monday-Friday from 9 am-6 pm, Saturday from 9 am-5 pm, and on Sunday from noon-5pm. We would be happy to hold a plant or two for your mother. Let us know if this would be helpful. You may also try some of the other garden centers in Louisville since they may have them as well.|
|Several months ago you talked about an ornamental grass, the picture showed it as a vivid yellow. I have lost the magazine; what is it called and where can I find it? Jill, Bradfordsville|
|Hello, Jill: The plant that was featured in the January issue of Kentucky Living magazine was amsonia, commonly known as Blue Star. It is a sun-loving perennial that has airy foliage with blue flowers this time of year. The picture was taken in the fall showing its stunning yellow color. You should be able to find this at your local garden center. You mcan just call around to see if anybody in your area carries it or if they would be willing to special order it for you. We at The Plant Kingdom in Louisville do carry this perennial and would be happy to hold one or more for you if you wanted to make the trip to get them. We are located on Westport Road and you can reach us at (502) 893-7333. Locally you can contact your County Cooperative Extension Agent to see if they have any suggestions or if they know anyone who grows them. Amsonia is a great plant that is somewhat whimsical in character. In my opinion it is a must-have for any sun-loving perennial garden. Let us know if you cannot find it locally. This plant has been very popular this year and we have shipped a few of them to gardeners who cannot find them in their area. We typically do not ship but there are always exceptions!|
|Someone stepped on my beautiful bleeding heart plant while it was still blooming. Most of the stems have been broken off at ground level. How do I save the plant or do I have to cut the entire plant down? Arlene, Colchester|
|Hello Arlene: We wait all year for some of our favorite plants to bloom in the garden and then when something like this happens it can be very frustrating, but the good news is that it did not kill your bleeding heart (Dicentra) though you will have to wait until next spring to enjoy the flowers again. Since the stems were broken there is no way for the plant to move moisture or nutrients to these parts so these stems will eventually die and will need to be cut back. If possible, it is important to keep as much of the foliage on the plant as you can. The foliage will collect much-needed nutrients for next year's flowers. These lovely woodland perennials tend to die back in the summer heat so it will not be an eyesore in the garden all year. For now, cut back just below where the stems are broken. Maybe some of them are just bent and not actually broken and if this is the case you can leave those alone. The plant may look a bit disproportioned but the roots were not damaged and so the plant will survive and thrive for years to come. Colchester, CT|
|The stems of some of my daylilies are hollowed out and the weight of the flowers causes some to break: what causes this? Woody, Morehead|
|Hi, Woody: Daylilies (Hemerocallis) are an old-fashioned favorite and are basically a given in most gardens these days. Thankfully they come in a wide array of colors. As a general rule these perennials are not subject to many insect or disease problems and none of them would affect the flower stem. Not to get too technical but the stem of your daylilies consists of different layers of tissue; though the thickness of each tissue layer may differ if you look close these herbaceous stems are all hollow. The thinner/weaker stems are certainly more vulnerable to drooping caused by heavy rainfall and/or high winds. Staking is always an option if you want them to be more upright or you can use them in a cut flower arrangement for a couple of days.
|We are going to do the bourbon tour this spring. What is the optimum time to see the flowers blossom? Dave, Rougemont|
|Hello, Dave: I am certain the bourbon will taste fine anytime of the year, but if your goal is to visit while the flowering gardens are at their peak you should plan your stay anytime from mid-April to mid-June. Technically spring begins March 20, but it can still be quite chilly and hit-or-miss in terms of flowering plants, so just as long as you wait until mid-April I do not think you can go wrong. Depending on the time you choose to go, there will be different plants in bloom since they all have their own bloom time. Mid-April will invite you with spring-flowering plants. Later in June you will get to see all different bloomers put on a show. Enjoy the bourbon and the scenery!
|We had some sedums professionally planted last summer and they were damaged by high winds/rain and actually broke the stem so the plant is lying sideways. What is the best way to care for these plants at this point? Jayme, Albertville|
|Hi, Jayme: Sedums are low-maintenance, hardy perennials that provide late-season color to the garden. They will tolerate a wide range of soil conditions and are drought-tolerant once established. Ideally they should be planted in a space where the soil is well-drained and they will receive a minimum of six hours of direct sunlight to be happy. They are succulents so less is better in terms of water. Taller varieties such as ‘Autumn Joy’ are good bloomers but as you have found out, they can become top heavy and easily broken or damaged by severe weather. At this point they make great cut flowers since the seedheads will dry on the stem. The flowers that have fallen over in your garden will not have any long-term effect on the overall health of the plant. As long as the roots are not damaged, new growth will occur and you will be able to enjoy your sedum year after year. Just prune back any damaged stems and dispose of them or use them as cut flowers. Leaving them on or near the plant will increase potential insect or disease problems so good sanitation practices are always a good idea. They are very tough plants so do not spend too much time worrying about them. I have no doubt they will be just fine. This is the most common problem we see with the taller sedums.
|What is the best way to kill the wild violet in my lawn ? Kevin, New Milford|
|Hi, Kevin: The common wild violet (Viola papilionacea) is a relentless perennial weed. Native to North America, it has become a nuisance for many gardeners. Eliminating violets from the lawn can be a daunting task and your lawn may never be violet-free, but keeping them under control is the goal. It may take a couple of years to get rid of most of the violets, but getting them under control in terms of population will help reduce new ones from popping up the next year. Wild violets are perennial broadleaf weeds that spread by underground rhizomes. It is best to dig them up as soon as you notice them so they cannot flower and set seed. Unfortunately, they have already flowered and set seed this year--when the grass was mowed the seeds were spread, so keep an eye out for new plants throughout the growing season and next spring. Hand digging is the most effective means of elimination because it removes the root system as well as any potential flowers. This task it much easier done with a weeding tool to ensure that you get not only the foliage but the fibrous root system as well. I realize this is quite an undertaking and depending on the space involved, hand digging may not be feasible. It is always much easier to pull these violets after a good rain. Wild violets have a waxy coating on the foliage that protects them against many common organic and chemical sprays. Using an herbicide containing 2,4-D
(2,4-dichlorophenoxyacetic acid) in combination with Triclopyr (Turflon or Weed-B-Gone) once in the spring as the foliage emerges and again in the fall will help reduce the population. Be sure to read and follow all recommendations when spraying any product in the lawn/garden. Do not be too discouraged when they keep appearing, this will be an ongoing job and requires a bit of patience.
|What type of perennials can I plant that will bloom at different times of the year, so I will always have something blooming from spring to fall? Stacy, Albany|
|Hello, Stacy in Kentucky: A well-landscaped perennial bed will provide you with blooms from early spring through the fall. This is easier in terms of flowers if you have a bed that is situated where it will receive a minimum of six hours of direct sunlight. You did not specify what growing conditions you are dealing with but you mentioned flowers, so I am going to speculate that you have more sun than shade. Let me know if this is not the case and I will give you other suggestions. Of course, numbers of plants will depend on the amount of space you have, and as a general rule we tend to plant in odd numbers for visual interest. As for early spring bloomers, daffodils (narcissus) are always a great choice. They scream spring and are planted as perennial bulbs in the fall. Those and crocus bulbs are some of the first to bloom in the early spring. Creeping phlox (Phlox subulata) and dianthus are both early spring bloomers. Later in the spring, baptisia, amsonia, perennial geraniums, peonies, and iris are all good choices. Summer bloomers include echinacea (coneflower), rudbeckia (black-eyed Susans), crocosmia, shasta daisy, perovskia (Russian sage), and coreopsis. Late summer and fall blooming choices include: solidago (goldenrod), aster, Japanese anemone, and amsonia, which blooms in the spring and is well worth planting just for its stunning fall color. These are just a few suggestions but you can visit the following publication for more planting suggestions for Kentucky gardeners: www.ca.uky.edu/agc/pubs/ho/ho76/ho76.htm
|What would be a good ground cover for a very shady area? Ginny, Somerset|
|Hello, Ginny in Kentucky: There are certainly options for shade-loving ground covers, but the plant selection will depend on what type of shade you are dealing with. Is there any filtered light at all or are you dealing with deep shade? Is it dry shade, meaning that you are planting under a tree where the roots are going to compete for moisture, or is there ample moisture? If you are planting under a tree, you will need to make sure your plants receive sufficient moisture while becoming established and potentially extra moisture during dry periods. The most common shade-loving ground covers are ivy, pachysandra, ajuga, plumbago, and lily-of-the-valley. These are all good options in terms of spreading habit. There are also a lot of shade-loving perennials that you might consider, the most common being ferns and hostas, but other possibilities include columbine, heuchera, tiarella astilbe, euphorbia, spigelia, bleeding heart, helleborus (Lenten rose), and acanthus. Depending on the space you are dealing with, it is sometimes nice to combine perennials to create contrasting colors and textures. In some cases a spreading ground cover is the best choice. At this time of year you are better waiting until spring to plant, but you can get the area ready for planting and ponder exactly what you would like to grow.|
|Where can I buy Spigelia plants? Peggy, Lewisburg|
|Hi, Peggy: Spigelia is a great native perennial; unfortunately it is not very commonly grown. You will have better luck finding it at garden centers that specialize in native plant material. I am not familiar with the garden centers or nurseries in your area so calling your local stores or contacting your County Extension Service for local suggestions will help get you on the right track. If your local centers do not typically carry this plant you can ask them if they would be willing to try to find it for you. If you have local farmers' markets this might be a good place to look as well. The following are links to Dropseed Nursery and Shooting Star Nursery here in Kentucky, who both specialize in native seeds. I did not see it on their list of available seeds but if you contact them they may be able to find them for you. www.dropseednursery.com/seeds.html
If you cannot find it locally or through mail order, The Plant Kingdom in Louisville does carry this plant when available but we have not been able to find it recently. We would be happy to let you know when we do. Our phone number is (502) 893-7333.
|Where can i find amsonia? Gary, Milton|
|Hello, Gary: Amsonia is a popular perennial this year. It is just breaking dormancy so it should be available soon. I am not familiar with the garden centers/nurseries in your county, but I suspect you should be able to find it locally. Call around to see if this is a plant that any of your local suppliers carry. They may be willing to special order it for you if this is a perennial they usually do not have. Your Cooperative Extension Service will have local suggestions for you if you need it. You can contact the Trimble County horticulture/agriculture agent(s) at (502) 255-7188 or stop by the offices at 43 High Country Lane in Bedford. If you are not able to find it locally, The Plant Kingdom in Louisville typically has it available in both quart-size and gallon-size containers. It is one of our favorite perennials so we keep it in stock; we do run out on occasion but we would be happy to hold one or more for you if you wanted to make the trip. You can reach us at (502) 893-7333. We are located at 4101 Westport Road in Louisville. Amsonia is a great addition to any sun-loving garden. It is light and feathery through the summer months with powdery-blue flowers, but the real show comes in the fall when the brilliant color emerges. The more sun the plant receives the better the fall color.
|Where in my local area can I find the bush that is shown in the Jan. 2010
magazine, amsonia? Joseph, Mount Vernon|
|Hello, Joseph: The perennial that was featured in the January issue of Kentucky Living magazine was amsonia, commonly known as Blue Star. I am sorry I am not familiar with the garden centers/nurseries in your area, so I cannot give you specific recommendations. Your County Cooperative Extension Service will be a reliable source of information for you. The Rockcastle County offices are located at 1050 West Main Street in Mount Vernon and the phone number is (606) 256-2403. The horticulture/agriculture agent(s) will be able to give you suggestions. You can just call around to the garden centers listed in the phone book to see if they carry this plant or if they could possibly get it for you. If you do not have any luck, let us know at The Plant Kingdom. We are located in Louisville so it would be a drive, but we would be happy to hold one or more for you if you wanted us to. Under normal circumstances we do not ship plants, but this one has been so popular that we have made exceptions to gardeners in Kentucky that cannot find this plant near their homes. We can be reached at (502) 893-7333.|
|Will a lily plant come back next year if it breaks at the bottom of the plant?
|Hello, Tasha: More than likely your lily will return and bloom next year. It is hard to say for certain but lilies are pretty tough plants and it has had quite a bit of time to store up nutrients for next year. Ideally, of course, we want the foliage to remain until the first hard freeze zaps it but at least this did not happen earlier in the spring. It is very likely that your plant will still put on new growth this summer. It would not hurt to give it a half dose of liquid fertilizer; nitrogen would be the most important since it promotes growth but any well-balanced fertilizer such as 10-10-10 will work. As long as the root system was not damaged and it was just the foliage that was taken back your perennial should be fine. Make sure it receives enough moisture, especially if this is a new addition to the garden. I am not sure why the foliage was removed but you may consider putting a border around it just to protect it for the rest of the season.|
|Winter is soon to start. I have perennials I did not get to plant yet. How can I save my plants? Can I put them in my basement during the winter? Laurie, North St Paul|
|Hello, Laurie: Winter is fast approaching and it always seems like there is one more thing to do in the garden before putting it to bed for the winter. We all run out of time and I can promise you that you are not the only gardener that has perennials that still need to be planted. Unfortunately it really is getting to the point where if you do not get them in the ground in the next week or so you are better off waiting until the spring. As the ground freezes and thaws it can heave up newly planted perennials that have not established their roots, making them more susceptible to winter damage. Over-wintering your perennials in their nursery pots is fine; the main concern is that the roots do not freeze. If you can dig a larger hole and place the plants in their containers in the hole, back-fill with the soil, and then add a layer of mulch, this will help to insulate the plants. Otherwise, you can place them in your garage or your basement if you have to. You do not want to fertilize your plants at all during the winter and only water when necessary. They are dormant at this time of year and placing them in warmer temperatures will confuse them, so no additional light is needed either. Because these hardy perennials would prefer to have colder temperatures during the winter months, if you have an unheated garage/shed this may be a better option. If you were dealing with tender perennials or tropicals then yes, your basement would be a good option. Unless of course your basement is cooler and does not have much light. Otherwise, leaving your hardy plants outside in their containers either buried in the ground or surrounded by pine straw or mulch to help protect them should be just fine. Keeping them close to the house will also provide some protection and radiant heat. Then you can get them in the ground next spring. Another option would be to create a mini greenhouse for them using plastic and bamboo or wood. If you have no other options, then by all means bring them into your basement to protect them.||