Germinating Seeds

How long shoulds seed germinate, how long should the root be before placing into the soil. And once the seeds are in the soil do i need to have my lites on?

it usually takes a few days for seeds to crack sometimes abit longer,,,,once the root is about 1 nd a half cm plant it root down in a hole about a inch deep lightly sprinkle some soil over it and gently pat the soil down keeping it fairly loose then spray some water on the soil till its wet and put ya light on....dont let the soil dry out at that stage.peace

ive got more germin rt now, well see tks