Gardening

The Best Time to Water Your Plants—& Why It’s Crucial

Yep, there's a best time to water them.

May 24, 2021
Photo by Ty Mecham

A perfect amount of rainfall is every gardener’s dream, but the reality is that almost every summer, there are stretches of hot, dry days when we need to water to keep our plants alive. The question of when it’s the best time to water your garden goes hand in hand with the question of how to water. To help you get the most out of that precious H2O, here are some watering basics:

Why Water Is Necessary

You’ll recall from biology class that water is necessary for plants to perform photosynthesis—the process of transforming water into sugar and oxygen when the leaves are exposed to light. But water does more than that, it also transports nutrients inside the plant, so even in the richest of garden soils, plants will be undernourished if the water supply is insufficient.

How Much Water?

The basic rule is that your vegetable garden or raised beds needs 1 inch of rain every week. So for every 100 square feet, that translates into 62 gallons of rain. If it rained but you don’t have a rain gauge and you’re not sure how much it rained, check the local weather information.

Or, check whether the soil feels dry 2 inches below the surface. If you mulched your plants, poke a hole in the mulch to get to the soil. Don’t go by how the soil looks; instead, stick your index finger in it to feel whether it’s dry. (This is one of the few gardening activities for which I don’t wear gloves.)

Join The Conversation

Top Comment:
“Using a hose is great if you can control the flow and you have the outside connection, but for those of us you have to physically carry a watering pot, checking the soil is needed even just to make sure that the soil is draining well, especially if you are growing a container garden versus in-ground plants. Soil drainage is important. During the growing season, you should be aware of your plants' needs so they thrive well.”
— cinamibun
Comment

There are exceptions to the 2-inch rule though—sandy soil lets water run through much faster than heavier clay soil, so it needs more frequent watering to make up for the loss.

When To Water

The best time to water is early in the morning when it’s still cool, which preps the plants for a hot day, but that’s not always easy to accomplish with a busy schedule. The second-best time is late in the afternoon or early evening. Unless you’re using drip irrigation or a soaker hose, watering in the late evening after dark is not a good idea, as the leaves won’t be able to dry off, which can spread fungi (tomatoes are prime candidates for this). That being said, always try to spray as little water on the leaves as possible and target the soil with your watering can or hose; don’t shower the plants from above. That’s why drip irrigation and soaker hoses are ideal—and they help you save water.

Again, there are exceptions to the early morning and early evening watering rule. If your plants look wilted, they are under drought stress. In this case, don’t wait—water them right away, even if it’s in the middle of a hot afternoon. The other big exception is with container plants, which need much more water than plants in the ground. They should be watered daily, even twice a day on hot days, until water drips out of the drain holes.

Go Into Slow Motion

When it hasn’t rained and the soil or the mulch layer on top is very dry, you should water very little at first, using the nozzle of the watering can or a spray nozzle of a hose, until the top layer is soaked; otherwise, the water will just run off. Be patient, as it can take a few repetitions until you see the water disappearing into the soil.

Plants That Need Extra TLC

Just because it hasn't rained for a while doesn’t necessarily mean that you need to water anything and everything in your yard. The motto here is: Water as needed. If a plant, even an established one, looks wilted and under drought stress, it needs water.

However, there are some candidates that always need your special attention: Anything newly planted (whether it’s a tree, a shrub, or a perennial) needs regular watering at least during the first year. In the absence of abundant rain, water it until the soil around the plant is well saturated.

Also, anything you have seeded needs to be kept consistently moist in order to germinate, whether it’s the lettuce in your garden or raised bed or the wildflower seeds you scattered. Unless it rains every day, you need to water those daily, and very gently, so you don’t wash out the seeds. Using a hose or a watering can fitted with a fine spray nozzle works best.

Do you have any other watering tips to share? Let us know in the comments!

See what other Food52 readers are saying.

  • Esse
    Esse
  • cinamibun
    cinamibun
  • Irina
    Irina
  • Smaug
    Smaug
  • AntoniaJames
    AntoniaJames
Writer, editor, and translator

11 Comments

Esse May 30, 2021
Good tips!
 
cinamibun May 29, 2021
It depends on the plant and the method of giving water used. Using a hose is great if you can control the flow and you have the outside connection, but for those of us you have to physically carry a watering pot, checking the soil is needed even just to make sure that the soil is draining well, especially if you are growing a container garden versus in-ground plants. Soil drainage is important. During the growing season, you should be aware of your plants' needs so they thrive well.
 
Irina May 29, 2021
Where can I find a same terracotta pots as it shown on this picture? What’s a name of it? Thank you.
 
Smaug May 24, 2021
Not bad as generalizations go, but don't let general rules stop you from considering individual situations. On very hot days (it may hit 120 for days at a time where I live) plants may have plenty of water in the soil and not be able to take it up fast enough through their roots. Practically all plants can absorb water through their leaves; spraying with water will cool the plant down and give it some added water- often enough to save it in a heat wave. Wilting plants aren't necessarily lacking water in the soil (though if a plant suddenly wilts on a hot day that's a pretty good guess). It may also be a sign of a compromised root system. This could be caused by gopher damage (or other subterranean creatures- it's usually gophers in my area.) It could be from getting dry enough to shrivel the roots (mostly for small plants and annuals) or too wet, starving the roots for oxygen and promoting fungus growth. Poorly draining soil and overwatering contribute to this. There are also fungus diseases that can plug the vascular systems of woody plants- this can be hard to spot and impossible to cure.
If you're using an automatic watering system, it's important to understand how it works and to check it regularly. These systems are very prone to malfunctions- most often connections coming apart or sprinkler heads falling off, and most people set them for very early morning so they never see the malfunction, which not only wastes water, it can result in no water where you want it and too much where you do. Also, hired gardeners tend to set them for excessive watering to make sure everything is green and lush.
 
AntoniaJames May 24, 2021
Great advice, smaug! You’re quite a gardening resource. I always learn something from your comments. ;o)
 
Smaug May 24, 2021
Thanks- I really am trying to be helpful; I realize that some people tend to find my way of expressing myself a bit abrupt. I have been gardening seriously going on 50 years- enough to give me a smattering of information on gardening in a couple of locations 15 miles apart, and a thorough respect for the vastness of the subject.
 
cinamibun May 29, 2021
The same thing occurs in the container plantings, you need to know what's going on with your soil, plus any critter visitors. I specifically changed the types of plants ( I mostly grow perennials) to discourage certain bugs (ants and spiders) and squirrels from digging. Every year gives me a new experience in maintaining the flowering members of my plants because the weather in my area (New York) doesn't follow the pattern for the grow area
 
Smaug May 29, 2021
Interesting about the squirrels- do you have something to stop them besides having the pot full or covered? Most years here they're just a nuisance for a few weeks in fall; unfortunately that coincides with the time I'm putting out a lot of pots of bulbs- bare soil until they sprout, to the squirrels- and newly repotted plants, and the squirrels go nuts planting acorns in them unless I cover them somehow. This (last?) year produced an acorn crop such as I've never seen, and I still have squirrels digging into my pots in late May. I guess I could grind up a bunch of Habaneros or buy a bunch of Cayenne, but is that any way to live?
 
4376ab May 30, 2021
Smaug, perhaps you can help me. I also live in a hot dry climate and have been told that my trees need to be watered if I want to keep them in good health. I don’t know how much or how often. Can you give me some advice? I have a regular hose, but should I get a soaker hose?
 
Smaug May 30, 2021
4376ab "Trees" covers an awful lot of ground. If you're in the western US, the ground water supply this year is severely limited, and plants that usually require no water may need it this year. For most trees, almost all, you want to water deeply, every 4-6 weeks at a guess. As with everything in gardening, there are a ton of variables- soil type, sun exposure, slope etc. There are devices to help- soaker hoses are pretty good; at any rate you want to spread the water around out to the tree's drip line (basically its shadow with the sun straight overhead)- a low sprinkler will do the job, but to avoid evaporation should be done very early, preferably on a day that's not hot or windy. I like to use a "root feeder"- a device that injects the water down 12"-18"; it's made for feeding, but I usually leave the food out; someone probably makes something just for watering- I'm not much of a shopper. There are far too may different trees to go into any detail, but I've found that in normal years trees more than a few years old require no irrigation; however, if you're irrigating anywhere in the yard tree roots will probably find it. By the way, if you leave a potted plant with a drainage hole on the ground- tree roots will likely find their way into the pot, making life very difficult for the plant.Fruit trees are a little different; for good fruit production most will require a fair amount of water. Underwatered citrus will produce scanty, often thick skinned fruit and production will be low with most. Figs do pretty well in hot dry areas, but they will search out water over a wide area. On the other hand, I have an apricot that I never water. It's production wouldn't thrill a farmer, but it turns out more fruit than I can use. Some ornamentals- Japanese Maples come to mind- also will probably need irrigation. If you're taking up gardening and you live in the west, I would recommend Sunset's "Western Garden Book" as an absolutely essential resource, and it could give you some more specific information on your plants. One would hope that whoever planted them chose trees suitable to your area- good luck with it.
 
4376ab June 1, 2021
Smaug,
What a generous reply! We are in central AZ at an elevation of 5800 feet so the drought factor is high. Our trees are a combination of needles and leaves (that shows you the extent of my garden expertise). I’ve ordered the watering spikes and book from Sunset. I feel that at least I can be giving these trees a boost to help them through the heat of the next season. The garden was in place long before we arrived, but the summers are hotter and drier than ever so a helping hand is in order.
An apricot tree sounds like heaven. Apricot jam, apricot ice cream, apricot tarts; what a luxury! Lucky woman. Thanks for being so kind with your advice.