As soon as you see roots trying to get out of the bottom is a good sign that you have a firm enough root ball for an easy transplant. They should be OK in the six packs until they are almost root bound but for most vigor transplant a bit before that. If you transplant when they are too small one bug could ruin your grow. You may want to consider a small cage for them if they're going out when real small. Good luck and good growing.

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