When it’s hot and humid out, most people can get themselves to a comfortable place, either in the shade or in air-conditioning. And once there, we can perk ourselves up with a cool beverage.
But that's not the case for garden plants, which can’t just pull up roots and move to a different spot. A University of Wisconsin Extension horticulture expert said that keeping an eye on how much moisture plants are receiving is the key component to gardening success.
During the summer months, plants rely on either rain or the garden hose to bring them some water. Many gardeners say that it can tricky to know how much rain has fallen during a shower or even a downpour, and the amounts can vary a lot in a small area.
Barb Larson, a UW Extension Horticulture Educator for Kenosha County , said she recommends a rain gauge as the best way to know what precipitation there has been so you can figure out what is needed.
“Deep watering is really important,” Larson said. “I talked to somebody this week that was having a lot of trouble with their vegetables, and we talked about how they were watering them. They were just going out with a hose and standing there for a couple of minutes and sprinkling it. … That’s not going to do it. Those roots are down a good 6 or 8 inches, and you have to get the water down to where those roots are.”
Deep, slow, and less frequent watering of about one inch a week is a good guideline to keep in mind. Once or twice a week instead of every day is better, as long as it is a good soaking, she said.
But how do you know if you’ve watered long and deep enough? Larson said that measuring is the best solution.
“One of the things I like to do is to use either a soaker hose or a trickle, or something like that, and run it for an hour or so, and then see how far down it’s gotten wet. … The easy way to do [that is to] use a bamboo stake or you can straighten a coat hanger, or you can use anything that’s kind of long and narrow," she said. "And then after it soaks in, I push that down into the ground and when I run into resistance, that’s the dry soil. Then I can pull it up, kind of mark the ground line with my finger, and see how far down it’s gotten wet.”
She said following this procedure gives her a baseline of how much water comes from that hose or sprinkler for that amount of time.
Soaker hoses, which release water slowly and directly onto the ground, are great for vegetables, but also for flowers, Larson said.
"(This is ) because it keeps the leaves dry. So, I can water during the day. I have one soaker hose where it’s kind of an ‘oozer,'" she said. "It takes so long for it to ooze out enough water to get down very far, I can even turn it on in the morning and let it slowly ooze all day, and then it off when I get home.”
Scott, a phone caller from Hayward, said he built nine raised beds for this year’s garden and decided to bury soaker hoses right in the beds about halfway down.
“So, that they’re really watering the roots. Actually, when it’s hot out, the soil seems dry on top, but it’s nice and moist down deep. It really seems to be working. Our garden is looking fabulous," Scott said.
Larson agreed that it’s a good approach.
“We have a number of master gardener  projects where they’re doing raised beds and several of them do that. It works really well,” she said.
She added that a good, organic mulch can help keep that top layer of soil moist, too.
Larson said the best time of day to water depends on how it's being done. The old garden wisdom is that it’s not good to water in the evening, but it really depends on how the water is being delivering to the garden.
Larson said that at UW Extension, they “don’t recommend in the evening if you’re using something like a sprinkler, so that you wet the leaves in the evening because it takes longer for those leaves to dry out. And that wet leaf surface makes them more susceptible to fungal leaf diseases. If you’re watering in the evening and you’re using a soaker hose, then you’re probably OK with it.”
If the leaves do get wet when watering, she said it’s better to do it when the temperatures are still rising, instead of falling.
Larson said that those who would like to install some soaker hoses to improve the health of their garden, but are afraid of the cost, they're in luck. For those with a little do-it-yourself spirit, people can make their own.  She also suggested keeping your eyes open on free recycling lists and even the curbside are good ways to find damaged but useable garden hoses.