Tomatoes Grow 3/4 Inch, Wilt, and Die

by Chris
(Ashby Mass. )

My tomato seedlings sprout, grow 3/4 inch, and die. They are under good light, 75 to 80 degrees in the day, at night maybe 55 to 60 degrees. Thanks.

Answer: Chris- this is classic wilt. This is usually caused by having the soil too wet (which excludes oxygen) combined with too cool temperatures. Powdery mildew and wilt love these conditions. I have two suggestions (maybe three) that should eliminate the problem.

First, when you mix up your seed starting soil mix, pre-moisten it. Mix it nice and evenly. It is the perfect moisture when you squeeze a fist full tightly and only get a few drops out of it. Next, fill the seed starting tray and pop in your tomato seeds as you probably did before. With a spray bottle gently mist the top layer of soil. As long as you keep a humidity dome over the seeds until they sprout, this is all the water they will need for now- do not water them more until they sprout and you remove the humidity dome and the top layer of soil goes dry.

In the meantime, you need to warm up the night time temperatures. Keep a thermometer next to the seed tray so you know for sure. The ideal temperature is 70-75 degrees. At 80 degrees, the seedlings will want to stretch (even if you have the light close). Somewhere around 65 degrees and less, you will begin having problems again with the wilt....especially if the soil is too wet.

Even though this is not exactly part of your original question- once the humidity dome has been removed and the seedlings are over an inch tall, they will benefit greatly from an oscillating fan. It creates microscopic tears in the tissue of the stem as they flutter in breeze a little bit. As the tomato plants grow and repair this normal damage it greatly strengthens the stem, so your plants will be able to stand up strong all by themselves and not be as loose as a cooked spaghetti noodle and leaning over or falling down.

Follow these recommendations as closely as you can, and you should have some dandy tomato plants to plant outside come May! I would love to hear how they turn out, and Happy Growing!