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Fertilizers

Can tomato fertilizer hurt your rose bush? Peggy, Zolfo Springs
Hello Peggy, You should not be too concerned about using a fertilizer that is labeled for tomatoes on your roses. Looking for the right fertilizer for specific plants can be a daunting task since there are so many options on the market. Both granular and water-soluble options are available in many formulations, and some fertilizers are best suited for specific plants, but as long as you do not overfertilize then it really cannot damage your roses. Overfeeding them can have the reverse effect in terms of flower production so this would be the main concern. A well-balanced fertilizer is fine such as 10-10-10 but too much nitrogen (the first number N-P-K) can cause leafy growth and prevent flower production, so avoid using any fertilizer with a higher nitrogen number. As with any product, always follow recommended application rates. It will be less maintenance on your part and more consistent in terms of available nutrients if you choose a granular plant food. These products do not need to be applied as often as water-soluble ones, and the nutrients are available over time as opposed to immediately with the water soluble options. Zolfo Springs, FL

Can you give me any information on GreenGanic? It's supposed to be the number-one fertilizer in New Zealand. Roy, Park Hill
Hi, Roy: I am not personally familiar with the GreenGanic product. All the information I have is solely based on literature as I have no experience using this fertilizer. As you mentioned, this product is made in New Zealand, it was developed in 1975, and since 2008 it has been available to gardeners in the States. GreenGanic is a liquid concentrate. This organic fertilizer has a base of liquid blood and bone meal. Blood, usually blood meal as gardeners use it, is a natural source of nitrogen that improves foliage color and encourages rapid growth. Although bone meal provides some nitrogen, it is typically used as a source of phosphorous as well as calcium. This promotes healthy roots and improves flower production. For more specific information on this product, visit www.greenganic.com. Before adding amendments to your soil, it is always a good idea to have your soil tested to know if it is lacking any elements. This can be done for a minimal fee through your county cooperative Extension Service. The Cherokee County Extension Office is located at 908 S. College in Tahlequah. The agriculture/horticulture agent(s) can be reached at (918) 456-6163.

I have leftover Miracid and Miracle Grow from last year. Is it good this year? Jane, Maysville
Hello, Jane in Kentucky: The answer to your question depends on the form of your plant food. Powder-based fertilizers should last for several years if properly stored in a dry space at room temperature. Liquid fertilizers, on the other hand, have a shorter shelf life and should be used within two years of purchase. Ideally they are stored at room temperature between 60 and 70 degrees F. If liquid fertilizers are subject to drastic temperature changes, especially freezing temperatures, this can cause separation to occur, changing the chemical composition of the product. Plant food comes in a variety of different sizes in granular, water soluble, and liquid form. You usually get a better price if you purchase a larger quantity but if it is not going to be used within a season it really is best to buy the smaller size and start fresh each growing season. That way there is no guessing whether or not your plant food is still viable.

Is it a good idea to fertilize plants that seem to need a boost or does that stress them even more? B., Lancaster
Hello, B.: The answer to this question depends on a few different factors. First, are we talking about plants in the garden such as perennials, shrubs, trees etc., or are we talking about houseplants or possibly annuals? If your answer is perennials or shrubs and they have been in the ground for a full year then yes, go ahead and give them some fertilizer. As a general rule any well-balanced fertilizer such as 10-10-10 will work fine, but in some cases there are different fertilizers for certain plants; if you could be more specific I can give you more detailed suggestions. Houseplants can be fertilized once a month durning the warmer months with your favorite liquid food, or you can also use a granular product that will only need to be applied every few months. Annuals will benefit from regular fertilizer every couple of weeks; again, you can use liquid or granular form. Compost is always beneficial and more economical if you have created your own. If these are plants that have not been fed in a couple of months, go ahead and give them a boost. Be careful not to overfertilize since this can actually burn your plants. Always follow instructions on the fertilizer package. If you have other concerns about these plants in terms of their health, you can always take a sample to your local garden center with a knowledgeable staff or your County Cooperative Extension Service.
Angie McManus Our Garden Expert Angie McManus will answer your questions.