Hi DC,

Welcome to the VIne. Earthbabe is spot on the only thing I'd add is when you've filled it & Lightly firmed the compost, stand the tray in a dish of water & you will see the surface goes darker eventually, this means it has taken all th eater it will need so you can stand it on the prop over night.

Also only use tap water as there may be pathogens in your water butt that will cause damping off of the seedlings.

__________________
ntg

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Remember that a lone amateur built the Ark.
A large group of professionals built the Titanic

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