It's easy to control your growing medium with young seedlings by using small container. Start with small coffee cups until they have 3 to 5 set of true leaves then transplant into small nusery container.
Young seedlings do not need any nutrients until they have three set of true leaves. First feeding should be a mild dose of B vitamins such as Liquid Karma,5ml per liter of water or B52, 5ml per liter of water ...

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