The tomato watering mistake almost everyone makes

Cracked tomatoes. Blossom-end rot. Fruit that tastes watery instead of sweet. Many of the biggest tomato-growing frustrations actually start with one simple mistake: inconsistent watering. Here’s how often tomatoes really need water—and the signs you’re giving them too much or too little.

But if you’re a newbie to the world of growing tomatoes, you may not be sure exactly how much water to give them. If they don’t get enough, the plants won’t fruit, or the tomatoes will be undersized. If they get too much, or if you water inconsistently, you risk mealy tomatoes, split skin, dry patches, blossom rot, or other issues.

How to Tell Your Plants Need Watering

While you might think a wilting plant is a sign that it needs water—and it sometimes is—it’s not the most reliable indicator. Young tomato plants can wilt in the heat, even if they have enough water.

The best way to tell is to feel the soil. If the top inch of soil feels dry and crumbly, chances are that your tomatoes need to be watered.

How to Water Tomatoes

The goal when watering tomatoes is to keep the soil consistently moist. If the plant spends too many days dry then gets a deluge of water, the fruit will develop dry patches on its skin, which then split when it attempts to grow—and the split skins can lead to rotting.

However—and this is important—you don’t want to douse the leaves or stems of the plant if you can help it. Moist leaves and stems can lead to unwanted fungal rot.

Therefore, the best way to water tomatoes is close to the ground, directly into the dirt around the base of the plant. Water deeply, so the water penetrates to the roots, and water regularly. Water early in the morning so any water that gets on the leaves can dry quickly; this will help prevent the spread of disease.

A drip irrigation system is also a great way to keep the soil consistently moist. And be sure to add a layer of mulch around the base of the plants; this will help prevent disease from spreading and water from evaporating.

How Often to Water Seedlings

Seeds and seedlings need the most frequent waterings, but they don’t need a lot of water at any one time. If you’re growing seedlings indoors or in small pots, simply make sure the soil is consistently moist to the touch. If you water them once or twice a day, don’t fully soak them, and don’t let the plants sit in water. Just make sure the soil doesn’t dry out.

How Often to Water Young Plants

As the plants grow, water them once a day or every other day. You’ll want to water them a little more deeply, especially as they get bigger, to help them develop deeper roots. If the soil dries faster, water them a little more often. If it remains moist for a couple days, then you can back off to avoid overwatering.

How Often to Water Mature Plants

Once the plants are mature and before they fruit, extension agents recommend 1 to 1½ inches of water a week. This can come from a rainstorm or the hose. The best way to tell if you need to get out and water is to set out a rain gauge. Keep a log of how much rain (if any) you’ve received and supplement what’s needed.

One exception is if you’re growing your plants in pots or other containers. Because more of the dirt is exposed to the environment, the soil is likely to dry out faster and may need to be watered much more frequently.

Other Factors to Consider When Watering

Some other factors to consider are the soil environment: if the soil you’re using is sandy and prone to dry out, your tomatoes will need to be watered more often (and may need some fertilizer as well).

If the soil is dense and muddy or clay, which retains a lot of moisture, your plants may need to be watered a little less frequently.

You’ll also want to consider what kinds of tomatoes you’re growing. Some plants are bred for growing in pots, for instance, with shallow root systems that need less water. Others that are bred to produce tomatoes all summer (instead of a single crop) and to grow in the ground, will have larger root systems that require a lot more water to stay moist.

For more care and tips, read our complete guide to growing tomatoes.