I recently planted some seeds and they all sprouted at about the same time. They've only been above the ground for a couple days and in that time they got way ahead of me. Long story short my lights were too far and they stretched. I moved the light (250w HPS) to about 8" today. I have a fan blowing directly on all of them so the stems should be thickening up. Do you think I'll have problems with them falling over when the leaves start growing? Anything other problems that letting seedlings stretch will cause later on? I attached a picture of one of them, they're all the same height.
By the way they are autos which I've heard don't like to be transplanted so that's why they're in such big pots.
I had this problem when I first started to grow from seed, the fan will help to get them stronger and adding a little extra soil couldnt hurt, just dont pack it down too much. Whenever my plants stretch or start leaning I find a stick to put next to them, tie them gently and it usually supports the plants for a while.
Either add a bit more soil, or just prop it up with something until the stem gets stronger. It's pretty common, especially first grows when people have their lights miles away. There's no harm done.
Thanks everyone, I appreciate the advice. I'll probably use a piece of bamboo skewer or something if they start leaning.
Honestly that isnt much stretching at all. Its normal for seedlings to a little. Just keep a fan on them to strengthen the stems and they should be fine now that you adjusted the light.
I also use a technique I read about called "tapping", or something like that. You just go in and lightly knock those kids around a few times a day with your finger. In my experience, putting a fan to blow on brand new seedlings increases the risk of drying them out unnecessarily. I use the tapping to give them a bit of exercise until they are mature enough to handle a constant breeze blowing across them. Putting a fan on stretched seedling stalks can also just blow them over if they are too weak, and tying them up prevents the movement needed to stimulate the hormones which drive the increased stalk strength.