SIOUX FALLS, S.D. (KELO)– Local gardeners are having to keep an extra eye on their gardens as the drought effects their growing season.
Heidi Teal, Co-Owner of Cliff Avenue Greenhouse and Garden Center, says that they are having a fantastic gardening season, since people are able to water their gardens.
“Of course, spring started off before the heat did,” Teal said. “Things have slowed down a little bit because of the heat, but it seems like on the weekend it picks back up again.”
Kristine Lang, Assistant Professor and SDSU Extension Consumer Horticulture Specialist said it has been hotter and drier a lot sooner this summer than it has in many years.
It’s important to water deeply and getting the water onto the soil, Lang said. Plants need approximately an inch of water per week, which is approximately 62 gallons of water per 100 square feet of garden space.
What you’re seeing right now is people over-watering, Teal said. They think it is hot and dry, so they think it needs a drink of water, but you should really feel down and see how dry it is and then decide if you should water then.
When watering, dig down, Lang said. You might see that the top inch is dry, but there may still be moisture two, three or four inches down, so you probably don’t need to water yet, but probably the next day.
Sometimes, when using overhead sprinklers or a watering wand, the soil surface will look wet, but you need to make sure that the water is actually penetrating into the soil and getting to the plant roots, Lang said.
“The root zone for plants can be within six inches, some crops like tomatoes can go deeper, at least twelve inches,” Lang said. “So, making sure that if the soil is completely dry, it’s actually soaking through the soil profile.”
During these conditions, Lang said you can expect to water your garden more than normal. Once plants are established and rooted in, you can probably deep water two or three times a week.
“Everyone’s soil is different,” Lang said. “As plants grow and produce more foliage, they are going to be using more water, but realizing those roots are going deeper.”
Trees and shrubs that have been established, are things that don’t need to be watered everyday, Teal said.
“If we stay dry with no rain in the forecast, if it’s established it should make it about every two weeks,” Teal said. “If it’s a newly-planted, your ground doesn’t dry out as fast as something in a pot, so you’re usually going to water about once a week at the most.”
Don’t be afraid to check everyday when using containers, Lang said. Especially for smaller, 10 inch containers or a hanging basket, you should be giving that a good soak and letting that water drain through everyday.
If you’re still planting annuals or vegetables, realize that the transplants have tiny root systems and they are going to need to soak everyday because the roots aren’t reaching deeper into the soil profile, Lang said.
If you’re planting new plants, Teal recommends checking on them once or twice a day because the plant’s roots haven’t reached out and hooked on to the soil, so they dry out a little bit more, especially when they are in the top few inches of the soil.
Once you can get the garden well watered and the roots grow, they can make it for at least one to two days without being watered, Teal said. But, if it stays this hot, and the subsoil doesn’t come back, you will water your garden almost every day depending on the size of it.
“We don’t need to water our plants, we need to water our soils,” Lang said. “So getting that water on the soil, if you’re hand watering, just watering directly on the soil. If sprinklers are your only option, running those really early in the morning is a lot more water efficient than watering them during the middle of the day.”
If you can afford and have the time to install a drip-irrigation system, this is the year to do it, Lang said. Those are low volume systems that put the water directly on the soil.
Another important thing to do is conserve water, Lang said. You can use natural materials as mulch, such as straw or hay mulch, which are great options for vegetable and annual plants. You want to put the mulch down four to six inches thick, as it will compact down. Mulch not only conserves water, but it also prevents weeds.
You can also use newspaper as a mulch to your garden from drying out so back, Teal recommended.
“This year, with limited water sources, anytime you have a weed growing in your garden, that’s competing with your plants for nutrients as well as water,” Lang said. “So getting weeds out of the garden means that there’s more water for your plants to have.”
If you planted cool season annuals, it’s important to realize that some of those are probably going to start to die back and stop flowering and more of the heat tolerant annuals are going to take center stage, Lang said.
“You can definitely still have flowers this summer, but think about some drought tolerant annuals,” Lang said.
Look for plants that have hairy leaves, Lang said, because that slows down the wind and we have experienced a lot of hot, dry winds in the area. By slowing down the wind, there is not as much water loss through transpiration. Thick leaves are also good because they hold on to water.
Native plants are always good because in South Dakota, the native plants are prairie plants and they’re naturally adapted, Lang said. These plants have deep root systems and they’re able to tolerate drought conditions. The plants may be smaller this year, because they are adapting to their conditions.
“They’re going to live this year, but they aren’t going to grow as large,” Lang said.
Some of the plants that Teal said are thriving this summer include geraniums, vinca and petunias. All vegetables do well when there is full sun. Your tomatoes, peppers, cucumbers, all will thrive in those conditions and you will see some growth, as long as you are in full sun and are able to water.
“Actually your garden really thrives in heat and full sun,” Teal said. “Where you see a little more trouble where you don’t get that nice producing of it is when it is a lot of cloudy, cool weather you see more diseases. When it is hot and dry, you see more bugs.”
For those looking to start their garden this late in the season, it’s tough, Teal said. It is hard to start things from seeds and find vegetables to plant.
“But like peppers, tomatoes, there are some squashes still available you can still get planted, but things that are your cool crops, like your broccoli, cauliflower, your cabbage, those are cool crops and starting them now with it being heat can kind of change the taste of it,” Teal said. “It kind of makes it…not very tasty.”
If you’re doing a lot of container planting, this would be the year to make sure that if your container mix is super well drained, maybe add some additional compost or peat moss to hold on to the extra water in those containers.
“Keeping container gardens watered this summer is going to be tricky,” Lang said.
A lot of times, when the ground and air are warm, your produce will be ready earlier, Teal said. When it’s cool and cloudy out, a lot of times, plants don’t want to put their flower on to produce the produce and that’s why when it’s hot and dry, it really seems to thrive.
At Extension, Lang said they have been receiving a lot of questions about why the tomato leaves are curling. If you see tomato leaves curling up, that is a physiological leaf roll. It’s more common in some varieties of tomatoes than others, but they are seeing it more this year because of the drought. This condition is not something to be concerned about, unless you are seeing weird growth or other types of curling.
You may see other annual plants curling during the middle of the day, Lang said. This is just because they are trying to conserve moisture and prevent the wind from having as much surface area.
Some stress signs you may see in your garden include leaves curling inward, browning on the edges of the plants and crispiness, Lang said.
“Sometimes drought stress does get confused with herbicide damage,” Lang said. “But realizing those times when we just see plant leaves curling and we don’t see funky growth, just realizing that it’s been unprecedented hot, dry conditions.”
For weed control, anytime you can pull the weeds or prevent them, whether you’re using a mulch or a woven landscape fabric, it’s important, Lang said. If you do make an herbicide application, remember that any of the plants you want to keep are super stressed, so that makes them more susceptible to herbicide damage.
You can find more information on yard and garden care the SDSU Extension website. They also have three garden hotlines across the state, where any citizen of South Dakota can call any location and ask questions. You can also find garden resources specific to drought on the SDSU Extension drought page.