Seedlings with curling leaves

ClarkB · 4 Weeks Ago

I've had lots of issues with unhappy seedlings indoors the last few years. It was very variety dependent - some were fine, but many had slow growth and curled leaves that would eventually fall off. This year I had several that started down that path. I'd been wondering if it might be temperature related as we set the thermostat to about 58F at night. Last year I purchased a large heat mat that I just put under the pots, which did not seem to help. This year I tried again putting the pots on the heat mat but also put large plastic bins upside down over the plants at night leaving about a 1" gap along one edge to allow some moisture to escape. I only plugged in the heat mat at night. The heat mat warmed the air around the leaves under the bins. After a few nights of this, all my sad seedlings looked much better. I continued that process for the rest of their indoor time (~3 weeks), and every seedling looked great. Getting them outside in the natural sunlight whenever the days are warm enough (~60F) also makes a big difference for me.

4 Weeks Ago	#39
ClarkB Tomatovillian™ Join Date: Mar 2020 Location: Syracuse, NY Posts: 32	I've had lots of issues with unhappy seedlings indoors the last few years. It was very variety dependent - some were fine, but many had slow growth and curled leaves that would eventually fall off. This year I had several that started down that path. I'd been wondering if it might be temperature related as we set the thermostat to about 58F at night. Last year I purchased a large heat mat that I just put under the pots, which did not seem to help. This year I tried again putting the pots on the heat mat but also put large plastic bins upside down over the plants at night leaving about a 1" gap along one edge to allow some moisture to escape. I only plugged in the heat mat at night. The heat mat warmed the air around the leaves under the bins. After a few nights of this, all my sad seedlings looked much better. I continued that process for the rest of their indoor time (~3 weeks), and every seedling looked great. Getting them outside in the natural sunlight whenever the days are warm enough (~60F) also makes a big difference for me.