Beat the heat and keep your plants healthy with a bit of strategy and a few tricks while southern states’ gardening.
The first year I tried gardening in Sugar Land, Texas, in the Houston suburbs, I harvested a grand total of four tomatoes. The fifth and final year I gardened at that house, I had so many tomatoes I had to buy a canner. In the interim, I learned that Southern gardens can be wonderfully productive, but it takes some planning.
Heat and humidity dominate every aspect of gardening in the South. High levels of rainfall can lead to fungal problems and acidic soils. Summers are hot enough to prevent many popular garden plants from setting fruit. The high heat and humidity together are ideal for all kinds of insect pests. Fortunately, there are ways to cope with all of these issues that don’t involve chemical sprays.
When planning your garden, ask yourself: How high is the drainage table? To avoid pooling and fungal problems, many gardeners use raised beds. When I made my raised beds, I used cinder blocks. This wasn’t the cheapest option, but heat and humidity break down untreated lumber within a few years. And treated lumber is usually treated with copper or arsenic, which I didn’t want near my food.
I lived about an hour away from the coast. The water table was high, so we installed drainage tiles adjacent to the vegetable garden. Between the raised beds and the drainage tiles, the vegetables never suffered from fungal problems.
After considering your drainage table, find out what kind of soil you have. Soils in the South are typically acidic, but gardening lime (calcium carbonate), which increases soil’s pH, is inexpensive and readily available. It’s also considered acceptable in organic gardening, so I added a small amount. I added lava sand and Texas greensand the first year for the minerals, but after that, our homemade compost was enough. If you’re unsure what kind of soil you have, state extension offices usually offer relatively inexpensive soil-testing kits. If your soil is acidic enough that you want to add lime, soil tests can help determine the proper amount of that too.
There are three main types of soil: Clay has the smallest particles, sand has the biggest, and loam has a good range of sizes. Loam is the most desirable for gardening, but if you don’t have it right away, don’t despair. Mixing organic material, such as finished compost, into the soil will improve its texture over time.
One of the biggest perks of gardening in the wetter South is the speed with which you can make homemade compost. The heat and humidity break down everything so quickly. I had a pile in a corner of the yard where we dumped our lawn and vegetable kitchen waste. I sprayed it with the hose every time I watered the garden, turned it occasionally, and dug finished compost out of the bottom of the pile twice a year.
My biggest mistake that first year – the reason I didn’t really harvest anything – was in my timing. I grew up in the Chicago area and had no idea how heat affected plants. I simply thought, “Well, Houston has a long growing season, so I can plant whatever, whenever.”
Nope! Heat affects plants almost as much as frost does. Tomatoes, for example, may struggle to set fruit if nighttime temperatures are above 75 degrees Fahrenheit and daytime temperatures are above 95 degrees, which is much of the summer. I found I needed to start my tomato seedlings indoors toward the end of January and set them out around Valentine’s Day to get them growing and setting fruit before the really hot weather showed up in May.
I needed to plant cucumbers and bell peppers early too. Bell peppers set fruit and develop well when temperatures are between 60 and 80 degrees. In the South, that’s fall and spring weather. Cucumbers still grow in heat, but their flavor suffers once daytime temperatures are consistently above 90 degrees.
My squash plants grew beautifully, but direct sun in the heat of summer wilted their leaves, along with the cucumber leaves. So, we put in a shade cloth, which is just burlap stretched over some wooden frames, to help de-stress the plants.
Once temperatures cooled in fall, I could just take down the burlap. Some Southern gardeners let their tomato plants live through summer and set another round of fruit in fall, and that’s definitely an option. However, I yanked my tomato and cucumber plants after harvesting all the fruit in late summer. This gave me room for fall vegetables.
My garden near Houston was Zone 9, which meant it did freeze every year, but the temperature rarely dropped below 25 degrees. As Northern gardeners know, many vegetables won’t be harmed by a few days of temperatures that hover around freezing.
So, toward the end of summer, I’d remove my spent tomato and cucumber plants, add finished compost, and then put in my plants that enjoyed cooler temperatures. We could get Swiss chard, carrots, and turnips through winter months until all danger of frost was past, and then it was time to return to summer vegetables.
Reading your seed packets is important when gardening anywhere, but it’s especially important in the South, because the intense heat restricts what you can grow. For the same reason, I also strongly encourage anyone in the South to find a locally owned and operated garden center. They’re far more likely to carry well-adapted varieties than national chains are.
Gardeners in the South are Zones 8 through 10, and knowing your Zone will tell you your area’s average low temperature. You’ll also need to know your average day for the last frost. In Sugar Land, my average last freeze date was around Feb. 15. If you’re unsure, you can check online or ask at a garden center.
Also, watch the weather forecast and exercise common sense. If your average last freeze date is approaching but so is an unseasonable cold snap, delay planting as needed.
Circumstances other than freeze dates affect how well plants will do too. The right varieties can make a world of difference. For example, onions come in varieties specific to day length. Gardeners in Chicago need to use long-day onions, while gardeners in Houston need short-day varieties. Gardeners in Nashville may get lucky either way, but if a Houston gardener tries growing a Chicago onion, the bulb won’t develop.
Some varieties also perform better in resisting insect attacks. The squash vine borer can cause a lot of trouble in Southern gardens, but Florida’s landrace ‘Seminole’ pumpkin (Cucurbita moschata) suffers less than other varieties.
Many popular vegetables are native to temperate climates, though cultivars bred to thrive in humid subtropical climates exist. You just need to look for them. And some lesser-known, but still quite delicious, edible plants are native to the South.
In general, native plants require the least amount of maintenance, because they co-evolved with the climate and other plants and organisms, including pests. If you don’t plan on moving anytime soon, many native plants provide delicious fruit. Persimmons (Diospyros texana), pawpaws (Asimina triloba), and scuppernong grapes (Vitis rotundifolia) are all native to the Southern United States and will require less maintenance than many non-native fruits.
I feel strongly about gardening organically for a variety of reasons and didn’t consider chemical sprays an option. Within two years, I found that providing good drainage and partial shade during the hottest time of the year, feeding my soil with compost, finding my ideal planting times, and using well-adapted varieties solved most of my pest problems.
Foliar feeding every two weeks helped as well. Texas gardening stores carried a mix called Garrett Juice, which I haven’t seen in other parts of the country. It was great! If you don’t have it in your area, you can order it online. Crop rotation was also important for breaking the life cycle of various pests. I had three sections of garden I rotated through, so nothing grew on the same ground more than once every three years.
Gardening in the South takes some investigative work and experimentation. Most of the popular gardening books and websites are aimed at gardeners in more temperate climates, though Howard Garrett’s Texas Gardening the Natural Way is a great resource for Southern gardeners who want to go organic.
The Southern states are lush and full of life. Many Southern gardeners harness that natural energy to create beautiful gardens. With some research and planning, you can too.
Joanna Silosky got really good at gardening along the Gulf Coast just in time to move to central Colorado, where she’s been gardening and raising animals for her family and friends since 2014.