Tomatoes Problems: Damping Off

Are you having problems with your tomato plants? Tomato seeds not sprouting, tomato seedlings fallin gover right after they emerge? Could be damping off. Learn more. Learn what to do.

What is it?

Damping-off is a common problem in tomato plants where the soil is too wet or has a high nitrogen level. This can be due to the watering conditions you have imposed on your tomato plants in the vegetable garden, or factors of weather such as damp days with many clouds.

What does it look like?

Tomato plants which are experiencing damping-off tend to have tomato seeds which do not sprout at all, or tomato seedlings which develop poorly and fall over soon after they have emerged from the soil. The stems of the tomato plants will appear water-soaked at the soil line and may be discolored in yellows, browns or blacks. Usually, a tomato plant which is affected by damping-off with have a soft, thin stem which is limp like a noodle which allows the plant to fall over easily.

How does it manifest?

Damping-off occurs when the soil has too high of a nitrogen content, or when the soil is too moist around tomato plants in the vegetable garden. This environment of wet, rich soil promotes damping off in tomato plants by allowing fungi to thrive and become more active in these moist, wet conditions. These fungi then infect the plants, weakening them further. The tomato seedlings grown in this rich soil environment also tend to be more succulent, which makes them more susceptible to attack from fungal and bacterial infections. Damping-off can progress rapidly when the weather remains wet and clouding during tomato seed germination, or when seedlings in the tomato garden are too heavily shaded by surrounding plants, trees, and structures. Damping off can also be a problem when you plant your tomato plants too early in the season. If you plant tomato plants too early, the soil usually has not had time to adequately dry after the winter melt and is not warm enough for quick, efficient seed germination.

What can you do about it?

In order to prevent damping-off of your tomato plants, be sure to start seeds in soil which has a proper nitrogen level. Do not plant tomato seeds in soil with even a slightly high nitrogen level, and if you feel the need to use a nitrogen fertilizer on your tomato plants, do so only after the tomato seedlings have emerged and have begun to produce their first actual leaves and foliage. Be sure that you do not plant any tomato seeds prior to the soil having reached at least 70° F outdoors. However, you may start seedlings indoors in sterilized containers and potting mix if temperatures don't reach 70° F soon enough in your area. Also be sure to protect seeds with a fungicide containing captan during their germination period. the best way to do this is simply add a pinch of captan containing fungicide to the seed packet, shake it up and then plant the seeds after they have been coated by the fungicide. You can also take most of these measures when transplanting tomato seedlings to make sure damping-off does not occur, and be sure that any tomato transplants you do place in your vegetable garden have the start of their first leaves and foilage before you buy them and place them in soil.

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