Crust on seed compost
Crusts have formed on all my trays of seed compost - does it matter and if so how do I prevent it?
It may.. depends on the power of the seedlings you have going. Does it have a crust even when moist? I would just sprinkle a bit of a different brand of sifted MPC or such over the top, to keep the crusty layer moist and uncrusty.