Story and Photography by Janet B. Carson
August gardening is all about surviving. The heat and humidity are usually at their peak, and rain can be spotty when it happens. Try to get your gardening chores done early in the day, and don’t forget to water. Water is the most critical factor for success this month, but unfortunately, there isn’t a watering formula that works in every yard. It all depends on what you are growing, what type of soil you have and how much sunlight the plants are getting. Container plants, in particular, can’t go too many days without water when it is hot and dry. Raised beds will also dry out more quickly than in-ground gardens. Daily watering does leach out nutrition as well, so more frequent applications of fertilizer will be necessary. Be sure to water the fertilizer in well and apply light applications so you don’t burn the plants.
If you are lucky enough to have a sprinkler system, monitor it occasionally when you are awake. Many gardeners run their systems while they are sleeping and can’t spot a broken head or a problem. Watering is best done early in the day so your plants are well hydrated before the temperatures get hot. If you don’t own a sprinkler system, then watering will have to occur when you have time. Even though you may not be as water-efficient watering mid-day, it is more important that you water. The key is to try and get it done before the sun sets; you want the foliage of your plants to dry before nightfall. Typically the temperature drops at night, humidity can rise and the chance for more diseases will occur with wet foliage. It is always best to water deeply than shallow sprays of water. Mulching will also help as it is more attractive than bare soil, but it also moderates the soil temperatures, holds moisture in and helps to keep weeds out. Weeds never seem to slow down, even when it is hot.
If you are taking a vacation this month, find a friend or neighbor to monitor your garden. If you have a lot of containers and you have a sprinkler system, try to group as many of your containers as possible in your sprinkler zones, so they can get watered while you are gone. If you have a vegetable garden, it is important that you also have someone check on it and harvest as needed. If overripe vegetables are left to rot on the vine, disease and insect problems will be a huge problem when you get home. And speaking of insects and diseases, it has been quite a year for them. From powdery mildew to leaf spots, stink bugs to Japanese beetles, we have had quite a range of problems. Scout all your gardens at least weekly and try to spot the problems quickly before they take over.
Now is a great time to take stock of your garden and find out what works in your yard and what doesn’t. Some annuals and perennials thrive in the heat of an Arkansas summer better than others. Lantana, periwinkle (vinca), pentas, begonias and zinnias tend to be strong performers in full sun. Coleus is another colorful foliage plant that can take sun or shade depending on the variety. Sunpatiens are doing fantastic in full sun to partial shade, and torenia and common impatiens are doing great in the shade, provided you are watering. If you have plants that have seen better days, go visit your local nursery or garden center. The amount and quality of plant material that is available all summer long is amazing. Often you can find some interesting new plants later in the season. From ornamental bananas to tropical vines and plants, they can give you blooms until frost which is still months away. Fertilize your annuals and tropical flowers regularly to keep them blooming. Use caution when using fertilizers and chemicals now. The combination of heat and humidity with fertilizer or chemicals can lead to some burn, so err on the side of light applications. Deadhead frequently to keep more blooms coming on.
Perennial plants that are thriving now include liatris, Echinacea (coneflower), agastache (hyssop), and gaillardia. Deadheading is important to prevent seed set which will encourage more blooms. Perennial hardy hibiscus is also still blooming. These plants should bloom from mid-June through August. Newer cultivars are more compact with the large dinner plate-sized blooms. Most lilies have finished blooming, and some are beginning to die back. Once dieback begins, you can cut the plants back. If you have irises that need dividing and you didn’t get it done last month, there is still time to divide, but make sure to do it soon. Be aware that iris plants usually don’t bloom well if they are overcrowded or in too much shade.
Annuals and perennials aren’t the only way to add color to a garden; we have some nice summer-blooming shrubs as well. Althea or rose of Sharon is still going strong, and we have lots of blooms still on panicle hydrangeas, abelia, and buddleia (butterfly bush). It has also been a stellar year for crape myrtles. They have been blooming well and will continue to bloom for another month or more. If you can reach the spent blooms, you can also deadhead these. Removing the spent blooms directs energy back into the plants instead of spending time producing seeds. This should encourage more rapid repeat blooms. We are still getting reports of the crape myrtle bark scale, but less than in past years. Those that have been treated with an insecticide are seeing at least two years or more of prevention.
Gardening can be challenging when it is hot and dry but having blooming plants and producing vegetables in all seasons is what we hope for. By working smart and getting things done early in the day — and watering — those goals can be met.