Summer Watering Schedule: How Often to Water Each Zone

The Summer Schedule at a Glance

In summer, water containers every day, give vegetable beds at least 1 inch a week split into two sessions, and check trees and shrubs planted in the last two years once a week. In a heat wave or in deep, sandy soil, vegetable beds may need up to 2 inches a week. Do all of it in the morning, and let a soil check overrule the calendar.

Zone	How often in summer	How much	Check before watering
Containers	Likely every day	Until water runs out of the drainage holes	Press a finger into the mix
Vegetable beds	Twice a week	Half an inch each time, 1 inch a week	Dig 6 to 8 inches down
Sandy vegetable beds	Often three times a week	Up to 2 inches a week in total	Dig 6 to 8 inches down
Seedbeds and new transplants	Daily on hot, sunny days	Keep the top 3 to 4 inches moist	Feel the surface soil
Trees and shrubs, first 2 years	When the weekly check finds dry soil	Deep soak	Feel the soil at 6 inches
Cool-season lawn kept green	Weekly	About 1 inch a week	None needed
Dormant cool-season lawn	Weekly	One-quarter inch; 1 to 1 1/2 inches once after 4 to 6 weeks dormant	None needed

The amounts include rain. A week that brings an inch of steady rain covers the vegetable beds, though pots under an eave or porch roof still need you.

Check the Soil Before You Water

A schedule is a starting point, and the soil gives the final answer. University of Maryland Extension’s method for trees and shrubs works anywhere in the yard: dig in with a trowel, a hand shovel or a screwdriver and feel the soil at a depth of about 6 inches. Water when it feels dry below the surface.

For vegetable beds, NC State Extension sets the goal as keeping the top 6 to 8 inches of soil moist. It also suggests checking your own work. Dig a hole 6 to 8 inches deep 30 minutes to an hour after watering and see how far the moisture went. If the soil is dry at 4 inches, the session was too short.

Water in the morning. University of Maryland Extension notes that watering in the heat of the day raises evaporation losses by as much as 40%. Clemson adds that early morning watering should reduce the chance of disease outbreaks, and that water belongs at the base of the plant, not on the foliage.

Containers: Likely Every Day

Plants in containers will likely need water every day during summer, according to NC State Extension. The mix volume is small, so there is little reserve.

Press a finger into the potting mix to check. When it is dry, water until it starts to run out of the drainage holes. University of Maryland Extension points out that several shallow waterings are not nearly as effective as one long application. Large containers hold more moisture and need water less often than small ones, and demand rises as plants get bigger and temperatures climb.

Two container problems catch people in July. Pots that sit close to a house, a building or a porch do not receive natural rainfall, so a wet week changes nothing for them. And a mix that has dried out completely resists rewetting. It takes repeated watering to rehydrate it, or you can stand the container halfway in a bucket or sink of water. Pot size and material also affect how fast containers dry, which the guide to containers for a balcony vegetable garden covers, and how often to water container plants in summer goes deeper on pots alone.

Vegetable Beds: 1 to 2 Inches a Week

Most vegetable and fruit crops need at least 1 inch of water a week from rain or irrigation during the growing season. That figure comes from NC State Extension, which adds that up to 2 inches a week may be needed in deep, sandy soil or during a heat wave.

Split the total. The same source recommends two applications of half an inch each per week. In very sandy soil, where water drains quickly, three applications a week are often needed. UF/IFAS explains why sand suits smaller, more frequent doses: in sandy soil a half-inch of water moistens down to about 6 inches, which it calls sufficient, and applying more wastes water. Tomatoes have their own routine, set out in how to water tomato plants.

It helps to know what an inch means in gallons. University of Maryland Extension gives 65 to 130 gallons per 100 square feet for 1 to 2 inches of water, the amount needed to wet soil at least 6 inches deep. For a 4 by 8 foot bed, that is roughly 21 to 42 gallons a week.

Some stages need closer attention. Clemson lists the first few weeks after planting or transplanting and the period when fruit or storage organs are developing as the times a shortage hurts most. For newly seeded rows, keep the top 3 to 4 inches of soil moist until seedlings are 4 to 5 inches tall, which can mean daily watering on hot, sunny days.

Drip lines and soaker hoses deliver water directly to the soil around the roots, with little lost to runoff or evaporation. NC State calls them the best way to water vegetables, herbs and fruits, and the guide to drip irrigation for a vegetable garden covers sizing a kit. If you will be away during the hottest weeks, see keeping the garden watered on vacation.

Trees and Shrubs: Young Plants First

New woody plants are the ones to watch. University of Maryland Extension’s schedule runs in two phases:

1. For the first 2 weeks after planting, check soil moisture daily and water deeply if the top 6 inches feels dry.
2. For the first two years after planting, check at least once a week and water if the soil feels dry at 6 inches.

When water is short, the same publication sets a priority order: young trees first, then shrubs, then herbaceous plants. Large, mature shade trees and shrubs can be left alone unless the drought is severe or they begin to wilt.

Lawns: Keep It Green or Let It Rest

Cool-season lawns such as Kentucky bluegrass respond to extended dry periods by going dormant: the foliage stops growing and turns brown. Iowa State University Extension says these grasses can generally stay dormant for 4 to 6 weeks without significant damage.

That leaves two workable plans. About 1 inch of water a week keeps the lawn green. The alternative is to let it go dormant and, if you can, apply one-quarter inch a week to improve its odds of survival. Once the grass has been dormant for 4 to 6 weeks, Iowa State says it is best to water it with 1 to 1 1/2 inches in a single application, which will not green it up but keeps the crowns and roots alive. Pick one and stay with it, because Iowa State advises against letting a lawn go in and out of dormancy through the summer.

Mulch and Soil Change the Numbers

Mulching vegetable beds with leaves, straw or bark reduces how much water they need. Around trees and shrubs, University of Maryland Extension recommends keeping the layer 2 to 3 inches thick.

Soil texture shifts the frequency more than the weekly total. Sandy beds need the three-session pattern because water moves through them quickly. Heavier soils hold water longer and do well on two sessions. If you are unsure which you have, the dig test after watering will show you within a week how deep each session reaches and how fast the bed dries.