Increase Success With Your Vegetable & Ornamental Transplants!

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Whether you are a commercial grower or a homeowner wanting to produce your own transplants, avoiding diseases, such as damping-off, will improve your chances of growing healthy transplants.

Damping-off is a common disease caused by several different fungi or fungal-like organisms that cause stems to collapse, typically at or near the soil line. Almost any plant can be affected by damping-off including vegetables and herbaceous ornamentals, so finding a variety that is resistant to damping-off is not practical.

Damping-off of tomato seedlings

Damping-off on tomato seedlings

Damping off on cucumber seedling

Damping off on cucumber seedling. Note the affected area near the soil line.

Instead, follow these simple steps to produce healthy transplants:

Clean trays and pots. The plant pathogens that cause damping-off usually are associated with plant debris or soil leftover from the previous year or crop that hang out in trays and pots. To avoid these unwanted “leftovers”, always use new trays and pots. 

Fresh potting media. Always use fresh potting media. Re-using potting media that you used last year will fail to produce desired results. Used potting media can harbor those unwanted damping-off fungi and doom this year’s crop. Plan to purchase just enough new potting media each year and avoid trying to “stretch” the use of your potting media.

Disease-free seed. Seed can harbor unwanted diseases. Purchasing seed from reputable seed companies is best because they test their seed to be sure it is free of disease. If you save seed, only select seed to save from healthy plants. Avoid saving seed from disease plants as some damping-off pathogens can be carried over on seed to the next crop.

If you must re-use trays or pots… Obviously purchasing new trays and pots is expensive and not very environmentally friendly. If you want to re-use trays or pots, be sure to rinse them with water first to remove ALL plant debris and potting media first as organic material, such as plant debris and soil, can inactivate the sanitizer and make it ineffective. Then, select a sanitizer from the PDIC Sanitation table to soak them in to be sure you have killed the pathogens. Homeowners can use a 1% dilute bleach solution.

More information can be found at this NC State disease factsheet: Damping-off in Flower and Vegetable Seedlings.

Healthy geranium seedlings

Healthy geranium seedlings