Continue fertilizing annuals (including those in your vegetable garden). Stop feeding perennials. Summer just started a month ago but during July outdoor plants that are winter-hardy in Tennessee (perennials) are already preparing for cold temperatures and dormancy. Home gardeners need to back off on fertilizing and pruning woody perennials by the end of this month to avoid disrupting that natural cycle. If you follow the typical southern hydrangea schedule of two feedings (May and July), either fertilize before the end of this month or skip the second application. I put one slow-release fertilizer tablet (10-15-10) for water lilies and pond plants in each gallon-sized container twice each season (May and July). There are gold fish in my water garden and fish waste supplies enough nutrients to keep floating water plants happy. My yellow water lily has been blooming its heart out this year. Summer annuals should be fertilized with a plant food formulated to boost blooms. A higher percentage of phosphate (the middle number) encourages flower and root growth. I normally add water soluble fertilizer to the plant water for containerized annual flowers. Because we had lots of rain this spring and I wanted to give the plants nutrients without dumping even more water on them, I adapted to conditions by switching to a solid time-release fertilizer this summer.    

Increase the number of hummingbird feeders from July through October. Those who feed hummingbirds will see plenty of additional activity if they hang up extra feeders now. As you may know, hummingbird nectar is made using 4 parts hot water and 1 part granulated white sugar. (For a small amount use 2 cups water and 1/2 cup sugar. Make a large batch with 4 cups water and 1 cup sugar.) Store prepared nectar in the refrigerator for up to two weeks. Male ruby throated hummingbirds drink as much nectar as they can find and eat as many insects as they can catch to build up fat which energizes them on their 600 mile migration across the Gulf of Mexico. Male hummers from Tennessee move to the Gulf Coast early in July but those flying in from further north keep passing through. Female ruby throated humming birds and immature hummers born this year, leave their nesting grounds about one month after males from the area depart. While only ruby throated hummers nest east of the Mississippi River, other hummingbird species are seen in our state during migration. Keep your eyes peeled for the occasional black-chinned or rufus hummingbird.

Clean bird baths and fill them with water during hot, dry weather. Birds seek out locations with water for drinking and bathing. Our feathered friends are fun to watch and many of them help gardeners by eating harmful insects.

Keep up the weeding. Weeds are survivors because they are able to out-compete desirable plants for resources. Prevention is important in the battle against unwanted plants. Don’t let weeds take over gardens or disturbed soil at the edge of your lawn, woods and other natural areas. When weeds freely reseed, just one can produce hundreds of seedlings. Pull them up before seeds form. Or dispose of seedheads separately while adding stems and leaves to your compost pile. Green plant parts are good nitrogen sources for compost. Most soils benefit from added compost.

Adult Japanese beetles are insect pests that eat plant leaves and flowers during June and July in Tennessee. Japanese beetle traps are not a recommended remedy. More next week.    


Plateau Gardening is written by Master Gardeners for those tending home landscapes and gardens in Tennessee’s Upper Cumberland Region. UT Extension Cumberland County at P.O. Box 483, Crossville, TN 38557 (484-6743) has answers for horticulture questions, free publications and details on how to become a Master Gardener. Send email comments or yard and garden inquiries to Master Gardener Rae,