Signs of overwatering in the tomato patch or in your potted plants are not uncommon, but they can be tricky. When soil holds more moisture than roots can take up, plants wilt. But they also wilt when the soil is too dry and plants need water. Drooping stems and foliage are often the first sign something is off, but you need to do a little more digging to find out if overwatering is the problem.
Here's what to look for when your tomatoes are getting too much water.
Signs of Overwatered Tomato Plants
- Standing water around the base of the plant
- Soggy soil or foul odor to soil
- White, green, or dark crust on the soil surface or lower part of the main stem
- Leaves and stems droop and wilt but remain green
- Roots are brown or black and limp or mushy instead of whitish in color and turgid
- Raised bumps and blisters appear on leaves
How to Inspect Tomato Plant Roots
Several signs of overwatering are easy to identify, but the surest way is to inspect the roots. If not corrected quickly, excessive moisture leads to root rot which prevents nutrient uptake and causes plant loss.
Most tomato plant roots grow in the top 8 to 12 inches of soil. Using your gloved hands or a small trowel, gently remove soil to uncover them.
How to Fix an Overwatered Tomato Plant
The good news is tomato plants are resilient. Identifying the problem early limits damage and makes it easier to revive the plant. Even plants with evidence of dying roots can be rescued. These are the steps that are most important for restoring good health.
Provide Dry Soil
If you see signs like soggy soil or standing water or if leaves and stems appear slightly wilted, it might be enough to withhold water until the soil dries out. When roots show signs of damage, you need to move the plant to a new, drier location.
Tomato Plants in Pots
Remove the plant from its pot, keeping as many roots intact as possible. Gently shake or rinse off soggy soil. Small, immature plants can be set out on newspaper for several hours to dry. Use a snipper to cut out mushy and discolored roots. Discard old soil and refill the pot with a new dry mix, then repot the plant. Add support to keep it upright.
Mature bush-type plants with small fruits respond better to transplanting than large fruit varieties, but should be placed in a pot with dry soil immediately. Rescued plants will lose leaves, but new growth signals a chance for a full recovery.
Tomato Plants in the Garden
Depending on the variety, garden-grown plants can have taproots extending to 3 feet to anchor top growth. Smaller roots that feed your plant are closer to the surface. It may not be possible to remove the entire taproot, however, a network of new roots will develop to take up nutrients.
Use a shovel to dig up the plant and remove as much soil as possible. Rinse the rootball under a faucet or gently spray set. Use a snipper to remove dark, waterlogged roots. Replant in a dry location in a wide, deep hole, spreading out the roots. Plant at the same depth as the original site. Add support to keep the plant upright and withhold water for several days to let roots thoroughly dry out.
Large mature plants with fruits and extensive root damage are difficult to salvage. They don't transplant easily and suffer extensive wilting when moved. These cases are best treated by allowing the soil to dry out followed by fertilizing. Treating soil around the base of the plant with a fungicide may help roots recover.
Roots feed plants by taking up nutrient-rich water. When overwatered, they become weak, inefficient, and unable to transport the nutrients needed for healthy top growth. When the soil and/or roots have sufficiently dried out, fertilize the water-damaged tomatoes with a balanced NPK fertilizer such as 10-10-10. Leaves can be treated with foliar spray but avoid treating foliage with severe wilt. Depending on the amount of damage, the plant should recover in one to two weeks.
Ways to Prevent Overwatering
- Avoid planting tomatoes in low areas where rainfall and water accumulate.
- Use pots with plenty of drainage holes.
- Set up a regular watering schedule.
- Allow the soil surface to dry slightly between irrigation.
- Watch the weather and track rainfall amounts.
- Allow 1 to 2 inches per week for garden plants and 1 gallon daily for potted plants.
- Hose timers are convenient but remember to account for rainfall and adjust accordingly.
- If you've missed a watering, don't try to compensate with additional irrigation. Adding too much at one time saturates roots.
- It's easier to hydrate a tomato plant than it is to repair one damaged by overwatering. If you need to be away, turn off timers and ask a neighbor, friend, or family member for a favor.
How long does it take for tomato plants to recover from overwatering?
Tomato plants recover quickly from overwatering, usually in one to two weeks with treatment.
How often should you water tomatoes?
In the garden, water plants deeply at the soil level once a week or twice weekly during hot weather depending on rainfall. Irrigate potted plants daily or twice daily depending on temperature and rainfall supplying a total of one gallon.
How wet should tomato soil be?
Soil should never be overly wet or soggy. It should be moist to a depth of 8 to 10 inches. Check by inserting a stick or probe. Moist soil will cling to the probe. Allow the soil surface to dry out slightly between waterings.