When to Water Your Vegetable Garden | Watering Chart

Watering Chart for Vegetables

May 29, 2019
Water Hose
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How much water do you really need? When is the best time to water your vegetables? See our tips on watering your garden—plus, a chart of when and how much to water specific crops.

According to some experts, less is often more when it comes to watering your vegetable crops. In areas without drought, a common mistake new gardeners make is watering too much!

Start With Good Soil

Healthy soil is the basis of healthy plants. You can’t just dig up dirt and put in plants. If you add a little mulch or compost, you are well on your way to making rich, well-balanced soil.

Regular applications of modest amounts of compost—one-quarter inch per season—will dramatically improve your soil’s water retention and help suppress disease. See our articles on soil types, soil testing, and the basics on amending your soil with NPK fertiliers and organic amendments,

When to Water

Don’t just water without thinking. Feel your soil! When the soil sticks in your hand and you can form it into a ball, it is moist enough. But, if it barely holds together in the palm of your hand, or if the surface looks hard, baked, or cracked, it is probably dry and it’s time to water.

It’s best to water early in the day so the foliage dries off by evening. When the plants are watered at night, the foliage stays wet for a long period of time and disease problems build up.

Believe it or not, sometimes the best time to water is during or immediately after a rainfall, especially if the rain shower amounts only to a half-inch or so of water. The reason for this is that you want to add sufficient water at the same time to ensure penetration down to 5 or 6 inches. If you wait another day or two to water, you will be adding only surface water, which evaporates rapidly. With only frequent, light watering (or rain showers), you never build up a reserve of water in the soil.

Lose Your Guilt About Wilt

Another sign is that the plants may wilt and look especially droopy. However, temporary wilting during the heat of midday does not mean that it’s time to water. Some plants go through an obvious midday slump, especially on very hot days, which is an indication of the plant’s natural adaptation to its environment. Visit your garden again in the early evening and see if the wilted plants have regained some turgidity. If they have come back—that is, if they look perkier—do not water.

Watering Guide: Critical Times to Water and Gallons Needed

To address the big watering question, below is a chart that tells you critical times to water each vegetable crop as well as the number of gallons of water needed.

This watering guide assumes summer vegetables and good, moderately-rich soil.  Water less often in cool spring or fall months. Water more often in hotter, dryer periods.

 Needs a lot of water during dry spells.  Needs water at critical stages of development.  Does not need frequent watering.
Vegetable Critical time(s) to water for a 5-foot row Number of gallons of water needed
Beans When flowers form and during pod development 2 per week depending on rainfall
Beets Before soil gets bone-dry 1 at early stage; 2 every 2 weeks
Broccoli Don’t let dry 4 weeks after transplanting. Head development.  1 to 1 ½ per week
Brussels sprouts Don’t let soil dry out for 4 weeks after transplanting. 1 to 1 ½ per week
Cabbage Head development. Water frequently in dry weather.  2 per week
Carrots Early root enlargement. Before soil gets bone-dry 1 at early stage; 2 every 2 weeks as roots mature
Cauliflower Head development. Water frequently for best crop. 2 per week
Celery Water frequently for best crop. 2 per week
Corn When tassels form and when cobs swell 2 at important stages (left)
Cucumbers Flowering and fruit development. Water frequently. 1 per week
Lettuce/Spinach     Water frequently for best crop. 2 per week
Onions In dry weather, water in early stage to get plants going. ½ to 1 per week if soil is very dry
Parsnips Before soil gets bone-dry 1 per week in early stages
Peas When flowers form and during pod-forming and picking 2 per week
  Peppers Steady supply from flowering through harvest 2 per week
Potatoes Tuber set and enlargement when the size of marbles 2 per week
 Radishes Plentiful, consistent moisture for root enlargement 2 per week
Squash Water frequently for best crop. 1 per week
Tomatoes For 3 to 4 weeks after transplanting and when flowers and fruit form 1 gallon twice a week or more

How to Measure Your Water

Another way to figure out how much water it follow a general rule of thumb of one inch of water per week. 

To measure overhead sprinkling, place 4 or 5 small containers (straight-sided) around the garden while the water is being applied. When 1 inch collects in the containers, that indicates that 1 inch of water was applied to the garden. Gardeners can recording the time needed to fill the container for timing future waterings.

How to Water

What you want in a healthy plant is deep root penetration, and the only way that you’re going to get deep roots is if there is water down deep.

Start at the very beginning: Saturate each plant hole when you transplant seedlings. When you do water, make sure that you get the soil saturated enough that the moisture percolates several inches down.

The disadvantage of using a sprinkler is that foliage is wetted by water dispersed via overhead application. This could lead to foliar diseases since the foliage remains wet for extended periods of time. An alternative is to lay the hoses directly on the ground near the plant so the water goes where it is needed. A board or rock placed under the water flow will prevent the water from eroding the soil. A good way to direct the water to the plants is to dig a little trench around the plants and allow water to flow into it.

Drip or trickle irrigation is also successful in the home garden. This is done mainly with hoses or plastic tubes with small holes in them that deliver a relatively small amount of water directly to the root zone; by supplying optimum moisture, periods of water stress can be avoided. The hoses or tubes are placed down the rows and water slowly trickles out. Regardless of method chosen, be sure to apply sufficient moisture.

Don’t Forget to Mulch!

Mulching is perhaps the #1 water-conserving technique for areas that receive less than 40 inches of rainfall annually. Organic mulches reduce evaporative moisture losses from the soil surface, and because the soil stays cooler, they also reduce transpiration water losses. Lay a thick layer of mulch down on top of soil. (Do not mix with soil.) Renew mulches that are in place for the entire growing season.

See our Mulching Guide for more information.

In Conclusion…

Don’t baby your crops; plants are incredibly adaptable. They have the ability to draw water from deep in the soil. Periodically, take a trowel and dig down several inches into the zone where the roots are most active. If the soil there is still moist, there would be no benefit from watering.

For more on watering the garden, especially in drought, read our article on “The Water-Wise Garden.”

See our video in which we will demonstrate the 10 smart watering tips for a healthier garden.

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Reader Comments

Leave a Comment

Watering

When I wrote promotional materials for Peters Professional Potting Soil and Plant Food, I discovered 30% of water is lost when irrigating by spraying water as opposed to using irrigation hoses.
I also find it interesting when experts suggest not to water a garden just before dusk, which supposedly can cause disease on wet plants. If this was true, then it had better not rain after 5 PM ever again in my garden! Plants seem to weather evening rain just fine.

watering

If I use drip or trickle irrigation can I lay the lines and mulch on top of them?

Watering a pallet garden

How often should a person water a pallet garden and how much at a time?

watering pallet garden

Because this garden is above ground, it will dry out more quickly. Like other containers, daily watering is likely. And your set-up should drain excess water to prevent root rot.

unwanted mushrooms

The last two years or so, we have been plagued with mushrooms coming up between the sidewalks and the lawn and in-between planted pots. The varieties are unknown to us (one is the common looking white button-top and the other is an elongated pink, pointy-top one). We have two young dogs who seem very curious and we are afraid they might eat them and become sick. How can we rid ourselves of the "schrooms" once and for all. We have tried soap, salt, weed killer, and shovel to no avail. We live in Albuquerque, NM so no overmoisture here!

Preventing Mushrooms

Look in your local garden center or hardware store for a pet-safe and lawn-safe fungicide. These are chemicals specifically formulated to get rid of fungi, such as mold, mildew, and mushrooms.

VEGETABLE GARDENING

I LIVE IN YUCCA VALLEY, CA. IT'S 98 DEGREES AND 70 OR SO AT NIGHT. THE WIND BLOWS 5 MILES PER HOUR FROM 10 A.M. TIL 4PM EVERYDAY. I WATER ONCE A DAY BUT YEILD IS NOT WHAT I'D LIKE. THE GARDEN IS SUN SCREENED. HELP??

yield troubles

The Editors's picture

To conserve moisture, make sure you provide a good layer of mulch around your plants. To prevent evaporation from wind, you might set up a windbreak. It could be, too, that it is not your watering but the heat itself that is affecting yield, as some plants slow down production in high heat. Sun screen is good to provide partial shade, especially during the times of strongest daylight. Perhaps next year, also look for heat-tolerant vegetable varieties. Your county’s Cooperative Extension might have further tips. For contact information, see: http://www.almanac.com/content/cooperative-extension-services  (At the California link, select “San Bernardino County”) Hope this helps!

Poor yields

I know this is a year late but also check your soil. I had to add better soil to one part of my garden .

Potted plants

When is water necessary for plants grown exclusively in pots? I live in apt and have several wild flowers that come back each year and also grow vegetables. Broccoli, squash, tomatoes and others. Thanks!

You can use the chart above,

You can use the chart above, even if you are gardening in containers.

I live in Fort

I live in Fort Lauderdale,Florida.Some days are really hot.My garden is,all about vegetable containers...do I water them twice a day or once a day? Because my tomatoes `leaves become yellow...do I need to water them until see water tp come out from the botton containers holes ? Thanks

It is easy to overwater when

The Editors's picture

It is easy to overwater when plants look stressed in the heat. Stick your finger in the soil to see how dry the soil actually is before grabbing the hose. Water when it is dry 2-3 inches down from the top. Yellow leaves on tomatoes are often a sign of overwatering or they could signal a soil deficiency.

tomato leaves turnig yellow

my experience tells me clearly having been a been a commercial organic grower of medicinal herbs which I specialize in and vegetable that a deficiency of nitrogen in the soil is usually the problem. If your soil has a high acidity level this disallowes the plant from drawing the nutrients it needs to grow naturally. Regards neil price a commercial organic grower of 20 odd years experience.

What is the best way to water

What is the best way to water Watermelon Plants & what type of feed should be given.I start mine from seed, but they don't seem to be doing well this year. Is there something I'm doing wrong

We planted more vegetables

We planted more vegetables this year. We have yellow pear tomatoes, Fourth of July tomatoes, lemon cucumbers, and a couple pepper plants. On this chart, the tomatoes and cucumbers are mentioned but not the peppers. Last year was our first attempt growing anything and it was cherry tomatoes. We had an over abundance! We just aren't sure how to care for this new garden. We have sandy, clay soil that gets FULL sun all day. Any advice on watering and care?

We'd advise having the soil

We'd advise having the soil checked again -- it won’t be both sandy AND clay. If it seems to be somewhere in between, it’s an ideal loamy soil, and full sun is good but in a very hot climate this may mean extra watering is required. The video has tips on watering -- tomatoes and peppers like plenty of water and it’s important not to let tomatoes in particular dry out too much before watering again, as the fruits can crack and it may also contribute to blossom end rot. Mulching is also important to help retain soil moisture.

I have a question about using

I have a question about using painted sticks as garden markers will the paint affect my garden

Hi, Momma: It sort of depends

Hi, Momma: It sort of depends on the paint type (should be outdoor), but it is hard for us to imagine much harm arising from this. Good luck!

Great tips! Sometimes when

Great tips!

Sometimes when you suffer from high water bills or dead grass, you might have a problem with your irrigation system. In the long run, installing the right irrigation system saves water and provides a healthy & beautiful landscape for your property :)

Is the "number of gallons per

Is the "number of gallons per week" column meant to list how many gallons per individual plant, or a 5-foot row like the "critical time..." column?

The number of gallons per

The number of gallons per week is for the 5-foot row, not the individual plants.

I am working on an article

I am working on an article that correlates plant water consumption and the one-inch of water per week rule of thumb. Runoff, percolation, transpiration, evaporation; plant spacing and that elusive well drained water retaining soil; it should all come together from the “Water Needed” column.

Used to garden big time in

Used to garden big time in Bakersfield, CA: SUN & FREE WATER!! Now I'm in Sacramento with a water meter and I'm at a loss as to how to afford the water. . .

Your best bet is to build a

Your best bet is to build a "reservoir" that will capture rain water. Build it up high, with a valve at the bottom, so that gravity can feed it for you. Otherwise you will need a pump to get it out. You can find out more about doing this online. You can really use this to save HUGE on water bills. Thank God I have a pump and a well where I live. Still pay for electricity though!

Robert Leavitt
leaveittoleavitt
Gardening on a shoestring budget

reservior

Robert, it rarely rains in CA during the summer.

Just dig your own water well.

Just dig your own water well. There are many websites with instructions on how to do thiis on your own, and on a low budget, I adapted the methods I saw to work at high elevation in North Texas. About $50 in PVC and another $30 added to the water bill I was able to use water pressure to dig a hole in the ground to the water table. Of course I had many problems, the you may not encounter as your a few hundred feet closer to sea level, I had to find the saturation zone, provided by lakes and rivers, you will find the saturation zone more shallow as the ocean is closer and helping bring the saturation level up.

Hi read your comments on

Hi read your comments on drilling our own well.Please could you provide details.I live in Cranbrook B.C. My understanding is this used to be an ancient lake.There are creeks that run under ground through the city in areas.and If this is of any help to you to help me I would appreciate it
Thankyou in advance
sincerely
Paul Valentine.

Drilling your own well.

Before drilling your own well always remember to check with local authorities to find out about any restrictions. It may save you a lot of time, trouble and expense.

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