Gardening in a Summer Sandhills
What a summer we have so far. Wait: it’s still technically spring, and we’re experiencing high temperatures and little rain, closer to summer time than spring. Plants are much confused with the yo-yoing of temperatures, long periods of rain followed by drought. And we are just in May!
As I like to say, in the Sandhills we are still four days away from a drought. It might rain every day for a week, but after four days of summer without rain, the plants will wilt and the sandy soil may be dry. One inch of rain (or irrigation) will provide the equivalent of about 600 gallons of water per 1000 square feet; most plants and grass need at least an inch of water per week to thrive. Soil types have varying “water-holding capacities”: sandy soil can hold about 0.75 to 1.25 inches of water per foot of soil, while clay soil can hold more than twice as much. more, up to 2.50 inches (with other types of soil falling somewhere in between). If it rains 2 inches, the sandy soil is not able to hold all of that rain, and some of it escapes and travels downward out of reach of the plants. Not only can clay soil hold more water than sand, it can hold it longer. So a two-inch rain can be sustained longer in clay soil, allowing plants to access water over time.
While it can be tempting to add clay to your sandy soil to achieve some of these benefits, it’s not a recommended practice (people have tried it, and it hasn’t gone well. , resulting in something closer to concrete than to the ground). However, here are a few strategies that can help you have a landscape that can somewhat withstand the ravages of a Sandhills summer.
Number 1: Plant your trees, shrubs and perennials in the fall for better establishment. Because plants don’t have to struggle as much to beat the heat in the fall, they are less stressed and able to put more energy into developing a strong root system. The benefits of fall planting mean the plant is better able to cope with heat and drought by the time summer arrives.
Number 2: Mulch your trees, shrubs, and perennials with pine bark, pine straw, or even fall leaves, keeping the soil covered. Soil temperature stays cooler, reducing stress to plants; mulch helps slow water evaporation and retain moisture longer. Mulch helps keep weeds under control and will eventually decompose, adding organic matter to the soil, which will also help increase the soil’s long-term water-holding capacity.
Number 3: Water early in the morning or late afternoon. This reduces evaporative water loss that occurs when watering during the heat of the day. This allows the plant to hydrate well before it gets really hot. Be aware that even a plant that has moisture in the soil can wilt during the hottest part of the day. Withering can be a physiological defense
mechanism, because wilting reduces the surface area of the leaves, which reduces transpiration (movement of water out of the leaves), thus reducing water loss. If a plant is watered during the hottest part of the day when it is trying to conserve water by wilting, it can cause stress to the plant.
Number 4: When it comes to turf, choose a strategy to deal with the drought situation and stick to it. Most warm-season grasses such as centipedes, zoysia, and Bermudagrass go dormant to withstand heat stress and drought. They will turn brown, but they will not be dead. When the temperature drops and the rain begins, they will turn green again. Note that this is not a strategy for fescue, which can be killed under these conditions. On the other hand, you can irrigate your lawn, preferably three times a week for about an inch to an inch and a half of water in total, if you want your lawn to stay green. If you embark on this strategy, you must stick to it throughout the drought. Watering sporadically, preventing the grass from going dormant for protection, but not providing enough to keep it growing, could cause difficulty and even death for your weed.
Finally, keep a rain gauge in your yard, so you can track rainfall to know how much irrigation you need to make up for the lack of rain. The rains in summer can be extremely sporadic, with an area receiving a downpour while the sky is blue a mile away.
For help and answers to your landscape questions, call us at the NC Cooperative Extension, Richmond County Center, 910-997-8255. Follow us on Facebook and visit our website, Richmond.ces.edu.
Paige Burns Clark is the Horticultural Officer and Director of the Richmond County Co-op Extension.