Looking for the best way to water your vegetable garden? Climates may differ, but the essentials of how to properly water a garden are the same everywhere. There are four key things to keep in mind to keep your garden thriving all summer long.

The best way to water your vegetable garden

Summer has arrived in California with record high temps, and in my garden we have already passed the point where the vegetables can get enough moisture from the soil. Until the rains start again in late October it is up to me to supply enough water to keep them alive. This is the most important summer gardening activity and if it isn’t done properly there really won’t be much of a vegetable garden to bother with.

Your climate may differ from mine, but the essentials of watering are the same everywhere. These are four things to keep in mind to make sure your garden thrives all summer long:

A close up image of a yellow sunflower with a small insect on the center, with green leaves behind itWatch your plants

If you know what to look for it is easy to tell when plants are suffering from lack of water. The first sign is that they lose the sheen on their leaves and start to sag slightly instead of standing rigidly upright. It is important to water immediately when you see this happening, as further stress will slow their growth.

More extreme signs of water stress include curling leaves, floppy growing tips, and dying leaves. All of these are signs the plant is severely distressed and has basically stopped growing, and is struggling to stay alive.

Simple wilting of leaves isn’t always a sign of stress however. Many plants (especially those with large leaves such as squash and cucumber) do it intentionally in hot sunny weather as a means of reducing water loss. They recover quickly when the temperature drops though, whereas water stressed plants recover more slowly. This is why you should check plants for water stress in the cool of early morning or evening and not in the midday heat.

Sunflowers are particularly prone to water stress. Because they wilt before almost anything else, they can be used as a living indicator of when the soil is starting to get dry before your other plants begin to suffer. Simply plant a few sunflowers in your garden bed and when they show signs of wilting, it is time to water the entire bed.

Image of a watering can watering plants in a garden. Photo source: Markus Spiske, UnsplashHow much to water

The general rule of watering says to give your plants 1″ of water per week in summer and about ½” in spring and fall. An inch of water means ⅔ gallon per square foot, or 66 gallons per 100 square feet, which should be enough water to penetrate 6″ to 12″ into the ground.

Though 1″ per week is a reasonable average to start with, it is only a guideline and will need to be adjusted to account for temperature, humidity, soil type, crop, and other factors.

It is better to look at the plants themselves and the soil they’re growing in to determine if you are watering enough, and then adjust accordingly. After watering, the soil should be evenly moist all the way down.

One of the most common mistakes beginner gardeners make is to water only until the surface of the soil looks wet and then move on. Appearances can be deceiving. While the top of the ground looks wet, an inch or so down the soil may still be completely dry. If your plants are wilting again within 24 hours you didn’t give them enough water.

Time of day to water

In hot weather you should avoid watering in the middle of the day, because any water that lands on the leaves, or that stays on the soil surface, will quickly evaporate and be wasted. It’s best to water either in the morning before the sun it too high, or early enough in the evening so that any wet leaves can dry out before nightfall.

How to apply water

Water should only be applied as fast as it can soak in. If you apply water faster than this it will puddle and the surface structure may break down. Excess water may also run off of the bed and be wasted, taking valuable soil with it.

The method you use to apply the water depends on your garden set up. Whether you choose to set up an irrigation system (soaker hose or drip irrigation), or if you prefer to hand water or use an overhead sprinkler system, it is important to keep in mind the water needs of the different plants in your garden, your climate and soil type, and what you find to work best for you.

Fortunately, all of that information is easy to find in the Crop Care tab in the Plant Guide for each plant in your garden plan. Smart Gardener makes it easy to keep track of each step of planning, growing, and harvesting your own food.

Two more things: compost and mulch!

To help conserve all that precious water you just put into the garden, it’s important make sure your soil is full of water-holding compost, and to cover it with a layer of mulch.

Mulch is an indispensable part of the vegetable garden, with a multitude of benefits. We’ve got tips to help you know how much to add and when to add it.

How to apply mulch to a vegetable garden

Benefits of mulching

Mulch is an indispensable part of the vegetable garden. Adding a layer of mulch over your garden soil will pay off in a multitude of ways by:

  • slowing evaporation of water from the soil
  • preventing weeds (many weeds need bare soil)
  • supplying nutrients to the soil (as it breaks down)
  • protecting the soil from damage by sun and air
  • reducing disease (by preventing soil splashing on leaves)

If a genetically engineered commercial product did as much, it would be patented, hailed as a miracle of science, promoted in all of the garden magazines and sold for a hefty price. Yet mulch does all of these things and more and costs next to nothing.

Types of mulch

How to apply mulch to a vegetable garden - Image of a child's hands planting a small tomato plant in the soil under a thick layer of straw mulchThe best all-around material for mulching your vegetable garden is straw. Straw comes neatly compacted into a convenient (if rather heavy) bale, is clean and easy to use and looks quite attractive on the bed.

Just be sure to avoid the similar-looking hay at all costs! It is full of weed seeds which can turn your soil into a weedy nightmare!

If you don’t have access to straw, you can use grass clippings or chopped tree leaves (run these over with a lawnmower to chop them, or put them in a metal bin and shred them with a string trimmer).

Compost can be used as mulch too, if you have enough of it. You can also buy the hulls of cocoa bean, cottonseed, buckwheat, and other types of silage (and even pine needles in some areas!) for use as mulch, but they can sometimes be more expensive when compared to straw.

When to mulch

If you are growing transplants, you will need to spread a 2- to 3-inch layer of mulch around the newly planted plants (it will settle as you water). Just make sure to keep the mulch about 2 inches away from the stems of your plants. If you are direct sowing seeds, though, you will have to wait until the seeds have germinated and the plants are a few inches high before applying it.

When not to mulch

How to apply mulch to a vegetable garden - Image of small seedlings sprouted in soil and mulchMulching is probably the most important thing you can do for your garden, except in a couple of important situations. Primarily, I don’t recommend using mulch if you have a problem with slugs in your garden because it provides the perfect hiding places for them.

Additionally, it’s a good idea to skip mulching in the early spring if you want the soil to warm up rapidly, as natural mulch creates an insulation layer, keeping the ground under it cool. Leaving off the mulch will allow the warming rays of the sun to warm the soil.

How often to add mulch

The beauty of using mulch in the garden is that, as a natural material, it will add nutrients to your soil as it breaks down. But because it breaks down, you will have to add more mulch from time to time. Generally I reapply a layer of mulch when I am first starting my planting and that will last through the season.

The good news is that this year’s mulch will be easier to mix into the soil for next year’s garden, giving you a jump start on preparing your garden bed.