| Yikes, don't be digging in that frozen ground :) I don't think your lettuce seedlings look especially rootbound. Floppy soft growth may be from your artificial lighting and they will probably become more sturdy when introduced to natural light...also too warm, or overwatering can lead to soft growth. Linked, pic of lettuce seedlings with adequate roots, but not too rootbound or in immediate need of potting up... |
Here is a link that might be useful: seedlings with roots