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Flowers - Annuals

Can you transplant sunflowers when they are in full growth? Joy, Harrodsburg
Hi, Joy: Sunflowers cheer up a sun-loving garden like no other plant. I would not recommend transplanting them while they are full grown. The answer to your question all depends on the stage of growth your sunflowers are in. I assume you are growing the giant sunflowers that will reach 6 feet or larger and not the small varieties. If you are referring to the smaller ones that only reach a couple of feet, those you could transplant. This is especially true if they have been container grown. When digging up the larger sunflowers, you risk not keeping intact all the roots and jeopardize the stability of the plant. That being said, if you must move them, it is essential that you dig up as much of the root ball as possible. Take your spade and start digging a circle a couple feet around the plant, making sure not to sever any roots. Dig as deep or deeper than needed to keep the root ball together. Transplant immediately and water well. This will give you the best chance of success. It is always a good idea to have your new holes pre-dug so you can immediately replant. The longer the roots are out of the ground and exposed to the sunlight and wind, the more stressful it is on the plant. Summer transplanting is not recommended for this reason among others, but if you must move them or lose them it is certainly worth the effort to try to save them.

How large a planter should you plant Next Generation sunpatiens? Debbie, Arlington
Hello, Debbie in Texas: The very popular impatiens is no longer just a shade-loving plant. Sunpatiens are a newer hybrid impatiens that thrive in sun and part shade. They may not be considered an annual where you are gardening, but for those of us in Kentucky these annuals will soon be available in our local garden centers. Sunpatiens can be grown in the ground or in a container. They prefer to grow in moist, well-drained soil and require no dead-heading. As for how many plants to put in a container, this will depend on the size of the container, the pot size you purchase the sunpatiens in, and whether or not you are making a mixed container or a single planting. Here is the thing about creating a beautiful container: it should look full and lush when you have finished planting it. Yes, the plants will grow larger and fill in but the roots of the plants can grow down as opposed to out so planting them close together at the soil surface is just fine. I am not saying to cram them in there but do not leave too much empty space either. Leaving about ½ inch between plants is fine. Make sure to plant all the way to the edge of the container. Start from the middle and work your way outward. If you are planting a combination of plants, place the taller ones in the center, the more compact around the center plants, and the cascading ones on the edge of the planter. There are three series of sunpatiens, vigorous, compact, and mounding/spreading forms, and all have different growing habits. The compact and mounding forms are best for containers. The compact will be more dense and bushy, reaching 2-3 feet tall, and the mounding/spreading form will grow 30-40 inches tall and 3 feet wide, so it would be good in a hanging basket.

I have a stock plant that I took out of the ground for the winter and put in my house; will that harm the plant and will it come back next year? Sue, Schenectady
Hello, Sue in New York: Stock (Matthiola incana) is considered a cool-season annual where you are gardening. Native to the Mediterranean, this plant can tolerate a frost but will not survive a hard freeze. They grow best in full sun and a nutrient-rich, well-drained soil. Stock plants flower best when temperatures are cooler during the spring and fall months. The plant itself will survive the hot summer months but it will not continue to produce flowers until the temperatures drop again. There are many cultivars of stock and they range in size and color, but they all are commonly grown for cut flowers and their fragrance. As for over-wintering this annual, it should come indoors before the cold weather arrives. It will be happiest growing in a sunny window or any brightly lit room. Your watering schedule will depend on the temperature and humidity of your home but once a week should suffice. You want to allow the soil to dry out before adding additional moisture. Some annuals are easier to over-winter than others and it will likely not produce flowers, but it's worth the effort if the goal is just to get it to survive until you can take it back outdoors next spring. Fortunately stock plants are readily available and easily grown from seed.

I have my potted plants (most in clay pots) on my porch. Will they live through 20 degree weather if they are covered? Brenda, Columbia
Hi, Brenda in South Carolina: The answer to your question really depends on what plants you are growing in your containers. Each individual species of plant has its own tolerance in terms of low temperatures. If these are hardy plants, meaning they can survive the low temperatures in your hardiness zone, then they should be fine. The main concern is that the soil does not completely dry out or become water-logged due to improper drainage. Since they are on a covered porch you will have to hand water every couple of weeks, but you want to avoid fertilizing until the spring. When we grow hardy plants in containers we have to remember that there is always a chance of loss due to the fact that they do not have as much insulating soil surrounding them as they would in the ground. On the other hand, if these are annual or tropical plants you are trying to over-winter, you are better off putting them in a warmer space. Most annuals/tropicals will not tolerate the lows you will experience this winter. As a general rule, most annuals do not over-winter well but tropicals do quite well when brought indoors to survive the winter months. They will be happiest when placed in a south-facing window or any brightly lit space. If you give me more specifics in terms of what you are growing I can give you more detailed information.

I have noticed just recently that my newly planted annuals are not doing so well, so I fluffed the mulch around them only to find the nightly watering I do is not getting down to the roots. The perennials that share the same beds have been doing really well. The mulch I have down is just regular mulch. Veronica, Milton
Hi, Veronica: Watering our annuals is crucial for their success. This is especially true in the extreme heat we have had early this season. Annuals in the ground may require less moisture than those in containers but until they develop a larger root system they will likely need to be watered three to four times a week depending on rainfall amounts. If they get a good soaking rain they should not need to be watered daily. Ideally watering should be done in the morning or afternoon while the sun is still out and the foliage can dry off before nightfall. When we water at night the foliage does not have a chance to dry off and fungal problems are more likely to occur. As far as your perennials, they will not require as much moisture as your annuals will since they have established root systems that can find water further down in the soil. Overhead watering with a hose is usually how annuals get watered in the ground. This is fine as long as they receive enough moisture but if you have a nozzle with a soaker option this would be great. This option helps the water to be released in a concentrated area as opposed to the regular shower spray that randomly sprays droplets of water. So next time you water, make sure to give your annuals a good soaking. Feel the soil to be certain before rolling up your hose. The mulch will help keep the moisture in but make sure it is not too thick; it should only be 2 inches thick. Otherwise it's hard for the water to reach the root system and too much mulch can create an environment for insects and disease to live. Your annuals will also benefit from a slow-release or water-soluble fertilizer

I overwinter our geraniums in the garage and I'm curious how the blooms dry and remain red all winter but are dead on this living plant? Richard, Simpsonville
Hello, Richard from Kentucky: To answer your question simply, some flowers lose their color as the bloom ages while others do not. This is why when people make dried arrangements with their cut flowers they are choosing specific ones based on how long the colors and the bloom itself will hold up. There are certain blooms that last longer than others. The topic of bloom color is actually more complicated than one might think. Not to get too technical but the color we see is really light reflected from different plant pigments. Anthocyanidins are the main group of compounds that make up these pigments. Our perception of these colors may differ depending on the time of day, light conditions, moisture/nutrition levels, as well as changes in temperature. The fact that your geraniums are moved to a cooler space out of the direct sun may have an effect on the color fading or lack thereof. The main reason for bloom color is to attract pollinating insects. Although as gardeners we might think the colors are specifically for our satisfaction, and in some cases the flower color has actually been manipulated by scientists for gardening purposes, but the real purpose is for fruit production. As colors fade it can be an indication to pollinating insects that their service is no longer needed.

I recently asked you a question about tropical sage that I purchased in Florida. Looking back at the bottle where the seeds were contained, the other name is "Salvia Splendens-Red." Does that help you to determine if the seedlings will survive Kentucky winters? Perhaps the name "tropical sage" was just a local name. Donna, Versailles
Hello again, Donna: I am glad that you still had the seed packet. Salvia splendens is commonly known as red salvia or scarlet sage. It is indeed an annual for us here in Kentucky since it will not survive our winter temperatures. It is native to Brazil and considered a perennial for those gardeners in hardiness zones 8-10. These plants are readily available each spring at your local garden center. If you still have some seed, save it and plant it next spring either indoors four to six weeks before our frost-free date or directly sow outdoors after May 10. These annuals attract hummingbirds with their spiky, tubular flowers, which are most commonly red but are also available in pink, white, purple, and bi-colored flowers. They are great for a splash of color in the summer garden or in a container. They also work great for cut flowers. Salvia require full sun for the best blooms and prefer to grow in nutrient-rich, consistently moist soil.

I recently moved from California to Louisville, KY, and would like to beautify a prominent balcony at the front of our house with some blooming flowers and attractive plants. Could you please recommend some container plants that are fast growing, easy to take care of, and have a long blooming season? How do I take care of the plants in the winter to keep them from dying? The balcony is in full sun during part of the day and shade in the afternoon. Laura, Louisville
Hi, Laura in Kentucky: Welcome to Louisville! Gardening in Kentucky is very different from gardening in California, and as far as container gardening goes if you want them to look lush and beautiful all year round it is best to change them out seasonally. This is especially true if it is blooms you are after. Winter containers can be challenging in terms of blooms, but this does not mean you have to sacrifice color. Planting evergreens in your containers for the winter months will provide you with winter interest, but you can also create your own arrangement by using cut greens such as magnolia, pine, arborvitae, chamaecyparis, or any other evergreen and then add berries, pine cones, and red/yellow twig dogwood or even curly willow branches to create different colors and textures. This will last all winter long and is as easy as sticking the branches in soil. You can pull them out in the spring and your containers are ready for spring planting. Cool-season annuals will be available in the garden centers late February/early March and these usually consist of pansies/violas, snap dragons, alyssum, and dianthus, among others; these will bloom until the weather turns really hot. Our frost-free date in Louisville is May 10. This means we are safe to plant warm-season annuals that will provide color all summer long into the fall. There are a lot more choices to choose from for filling your containers this time of the year. A lot of these options may have been perennials for you in California. As the cooler temperatures arrive, the cool-season annuals will once again make an appearance and shortly thereafter we will be designing our winter arrangements for another season. Unfortunately there are not any plants that will bloom all year long or even survive in our containers all year long unless you want to plant evergreens and plant annuals around the base, switching them out as the seasons change. As with all containers , make sure they have proper drainage holes and are filled with a good potting mix. If you need suggestions for reputable garden centers in Louisville, The Plant Kingdom on Westport Road and Wallitsch on Hikes Lane are both great choices.

I'd like to plant tropical sage starter plants that I obtained from Florida in my Kentucky yard. However, will the plants survive the Kentucky winters? And if so, do I need to cut them back at the end of fall? Donna, Versailles
Hello, Donna: Tropical sage is a common name for many different varieties of Salvia. This is a large genus of plants that are available in a variety of colors and are a favorite among butterflies and hummingbirds. Any plant that is sold as a tropical is not winter-hardy for those of us gardening in Kentucky. There are some Salvia that are herbaceous perennials in our zone, but it does not sound like the plants you have purchased are winter-hardy. Was there a grower's tag in the plants? They can certainly be outdoors for now but before the first frost arrives, bring your plants indoors and place them in a south-facing window or any space where they will receive good filtered light. Treat it like any other house plant and cut back on the water as well as food during the winter months. They will not likely bloom during this time, but the idea is just to keep them alive so that after May 10 they can be taken back outdoors and gradually acclimated to the full sun. This way they will not burn and the transition is less stressful on the plants. Depending on how many plants you have, you might experiment and plant one in the garden in a protected spot and see if it over-winters or re-seeds in the garden.

It is okay to cut back annual empire red salvia when the blossoms are spent? Judith, Newnan
Hello, Judith in Georgia: Salvia splendens ‘Empire Mix’ is a popular sun-loving annual. This mix is available in an array of colors but red seems to be the most sought after. These plants are prolific bloomers, and given the right growing conditions they will provide color in your containers or garden all summer long. As the blooms fade it is a good idea to remove them since it will encourage the plant to use its energy to promote more flowers. Spent flowers are not aesthetically pleasing either, so you have two good reasons to remove them. Take the flower stalk all the way back while leaving the foliage. The foliage is needed to collect nutrients in order to encourage new blooms. These annuals can reach 12-18 inches tall and should be spaced 6 to 8 inches apart. They will tolerate intense heat as long as they are given sufficient moisture and they will benefit from a weekly or biweekly dose of your favorite liquid soluble fertilizer. If you use a slow-release granular food you will not need to feed this often. If your salvia is planted in a container it will need to be watered daily as we get into the heat of the summer. If they are planted in the ground and Mother Nature does not provide moisture for a few days, you will need to hand water your annuals.

My citronella geranium has abundant new growth at the base. Can I cut back the large top growth to allow the new growth to take hold? Beverly, Broken Arrow
Hello, Beverly in Oklahoma: Citronella scented geraniums (Pelargonium citrosum) are nice for repelling mosquitoes. They are grown for their aromatic characteristics as well as their foliage. It is certainly fine to remove some of the older foliage. In fact, this is beneficial in terms of encouraging new growth. The plant does not need to use up its stored nutrients on the larger/older growth that may not look so good; instead it can concentrate its energy on putting on new growth. It sounds like your plant is happy and geraniums are nice low-maintenance houseplants if you are interested in trying to over-winter it indoors. Bring it indoors before the first frost and place it in a sunny window or any brightly lit room. The light levels are much lower during the colder months so there is no need to fertilize. Your plant will not need to be watered as often as it does now since the temperatures will not be so extreme. For now take a pair of gardening scissors or pruners and remove the older foliage all the way back to the base of the plant.

My class has been working at our local greenhouse an I'm in charge of the flowers that we will sell. I was wondering if I could get a list of flowers (and the info about those flowers) that are annuals and can grow in Maysville, Kentucky. Samanatha, Maysville
Hello, Samantha in Kentucky: What a wonderful project you are involved in and a great way to get kids playing in the dirt! Annuals are separated into two different categories: sun and shade. Some of the most popular sun-loving annuals are petunias, lantana, verbena, salvia, pentas, and zinnias. Some common shade-loving annuals are impatiens, torrenia, caladium, and coleus. These are just a small fraction of the annuals that we grow in Kentucky. The list is entirely too long for me to just rattle off names and detailed information about growing them, but the Cooperative Extension Service is a great resource for home gardeners and they provide publications on many different gardening topics such as annuals for Kentucky gardeners. For more detailed information on which annuals to grow and details on how to propagate them, you can visit the following links: www.uky.edu/Ag/Horticulture/gardenflowers www.ca.uky.edu/agc/pubs/ho/ho47/ho47.htm www.ca.uky.edu/agc/pubs/ho/ho56/ho56.htm You can also contact the horticulture agent at the Mason County Extension office for copies of these publications. Their Web site is http://ces.ca.uky.edu/mason or you can reach them at (606) 564-6808.

My snapdragons keep dying this year. Can you tell me what's going on? Barbara, Bowling Green
Hello, Barbara: Not knowing the growing conditions of your snapdragons, it is hard to say for certain what is happening with them. Are you growing them in the ground or in a container? If they are in a container, make sure it is filled with a loose potting mix for containers and the container itself has a drainage hole. Snapdragons do not like to have “wet feet”: if the soil does not drain well the roots can rot. The soil should be consistently moist but not allowed to go bone dry. These annuals bloom best when they are planted in full to part sun. This means they should receive a minimum of four hours of direct sunlight. During the middle of the summer, they will benefit from shelter from the hot afternoon sun. Snapdragons like the spring and the fall the best in terms of growing conditions. In mid summer, they tend to wilt especially if they get all day sun. These annuals are available in a rainbow of colors and they are great for cut flowers. They will benefit from a well-balanced (10-10-10) slow-release fertilizer for the season or a liquid fertilizer every couple of weeks.

Please advise me of how I may contact the lady on the front cover of the March 2009 magazine. I am interested in purchasing the giant sunflower seeds shown on the cover. Viviane, Mt. Washington
Hello, Viviane: Thank you for your question. Esli Pelly and her wonderfully creative garden gifts are featured on the cover of the March issue of Kentucky Living magazine. Her business is The Garden Patch in Smiths Grove, Kentucky. I was unable to reach her to find out exactly what sunflowers she grows, but the phone number to the store is (270) 563-3411. If you are ever in the area the store is located at 1085 Hayes-Smith Grove Road. Just looking at the picture we can see that she is growing one of the giant sunflowers. There are many to choose from, including Mammoth, Lemon Queen, and Large Grey Stripe. Renee’s Garden is a great source for sunflower seeds. Check with your local garden centers/nurseries to see if they carry them. ‘Sunzilla’ is a giant edible available from Renee’s Garden. You can also purchase these online if your local sources do not carry them. Visit www.reneesgarden.com.

The rain gave my geraniums a real beating and the blooms are really low to the ground. Will they stand back up? Bertha, Donalsonville
Hello, Bertha in Georgia: Heavy rain and in climate weather can be damaging to our plants. Typically they will stand upright again but it really depends on if the stalk of the flower was damaged or not. If the blooms were fading and the stalks were not sturdy enough to withstand the heavy rain they may not stand up again. Fortunately, geraniums are prolific bloomers and will continue to provide you with lovely blooms all summer long. If the blooms do not stand up within a day or so go ahead and cut them back. You can enjoy them as cut flowers and removing them from the plant will encourage new flowers to form. Geraniums thrive in full sun and well-drained soil, and will benefit from a weekly or biweekly dose of fertilizer. Either liquid or granular is fine but make sure to follow recommended application instructions for your favorite brand. Too much fertilizer can actually have the oposite effect in terms of blooms. A well-balanced fertilizer is fine such as 10-10-10 or you can use one that has a higher potassium (third) number, which will promote blooms.
Angie McManus Our Garden Expert Angie McManus will answer your questions.