How Often to Water Tomatoes, Plus 7 Tomato Watering Tips (2024)

Figuring out how often to water tomatoes can be a challenge for beginner and experienced gardeners alike. Excessive watering can result in diseased plants and rotten tomatoes. But not watering often enough may weaken plants and give you small, mealy fruit. The trick is to pay attention to your soil and the cues your plants give you so you can grow armloads of delicious, juicy tomatoes. These tips will help you figure out exactly how often to water tomatoes for the best harvest.

Know Your Soil

The best soil for tomatoes is moist to the touch but not sopping wet.Be wary of soil that is dripping with water when you squeeze it together in your hand; too much soil moisture limits the oxygen available to plant roots, slowly suffocating the plant. Soil that is excessively crumbly, dry, or dusty has very little moisture available to plant roots.

Soil that contains a lot of sand doesn't hold water well and dries quickly. Because of this, tomato plants growing in sandy soil may need to be watered more often, about every three or four days. Clay soil, on the other hand, holds water well. Plants growing in clay soil usually only need to be watered once a week. Tomatoes growing in pots often demand daily water because the limited soil volume in containers dries out quickly.

The very best way to know if it’s time to water your tomato plant is to grab a handful of soil from a couple of inches below the soil surface. This is dirty work but is truly the most accurate way to know if you should add more water. If the handful of soil feels moist, wait a day and check it again. But if the soil is dry to the touch, water the plants deeply.

Water Needs Based on Growth Stages

Tomato plants have different watering needs based on their growth stage. Make sure you're giving your plants exactly what they need, based on their size and when they were planted in your garden.

1. Seedlings

Your tomatoes need to be watered the most frequently when you first finish planting their seeds. Make sure the soil is damp well below the surface so the roots can establish themselves. If you're using a spray bottle during this stage, you should only need four or five squirts for your tomato seedlings to get the proper amount of water.

2. Young Transplants

Consistency is most important during this stage. Make sure you're giving your newly transplanted tomatoes a good soak. When the soil gets dry, repeat the process.

3. Mature Plants

Pay close attention to the weather during this time. If it rains enough, skip watering and if it's hot and dry, water more so that your plants get at least an inch of water every week. A rain gauge can help you determine exactly how much water is required.

4. Fruiting Plants

Once the fruits set, reduce the volume of water you give your plants during each watering but water more frequently. During this stage, overwatering could cause splitting. However, underwatering could cause the plant to produce less fruit.

Tips for Watering Tomato Plants

Once you've figured out how often to water tomatoes based on your soil's moisture levels and the plant's life cycle, use the following tips for watering your tomato plants properly.

1. Deliver water to the base of the plant.

Avoid getting leaves and stems wet when watering tomatoes. Bacterial and fungal tomato diseases are spread more easily when the foliage is wet. Instead, deliver water directly to the base of a plant using a watering wand, drip hose, or watering can with a long spout.

2. Water slowly.

Water from a fast, heavy rain shower often flows away from plants instead of soaking into the soil. The same is true when plants receive a blast of water from a garden hose or watering can. Turn down the flow on your garden hose or water slowly when using a watering can. Better yet, use a drip hose to slowly soak the soil.

3. Soak, soak, soak.

When watering aim to soak the soil to the depth of 10 inches. Deep watering promotes a deep root system. A deep root system will not only anchor the plant in the ground well, it will also equip the plant to reach far and wide for water when needed.

4. Check the depth.

After a watering session, use a garden trowel to dig a narrow, 10-inch-deep hole about 5 inches from the base of the plant. If the plant has been watered adequately, soil at the bottom of the hole will be moist. Adjust watering time in the future if needed.

5. Add a layer of mulch.

Conserve soil moisture by spreading a 2-inch-thick layer of organic mulch over the root zone of a tomato plant. The mulch will insulate the soil, preventing big temperature swings. Mulch also helps to keep water-stealing weeds at bay, and will slow down soil moisture evaporation. Shredded bark mulch and weed-free grass clippings are good choices.

6. Check containers daily.

Tomatoes growing in pots have high water needs. The relatively small soil volume in the container limits the amount of water available to plants. During the heat of summer, container-grown tomatoes often need to be watered daily. Hot, windy conditions might require twice daily watering.

7. Water early in the morning.

In order to keep the soil moist throughout the heat of the day, you should be watering early in the morning. If you water in the afternoon, plants may already be stressed from lack of moisture.If you water too late at night, cooler and damp conditions could promote diseases.