i wondered if there's a certain type of soil I should plant my lilac trees in and will they be ok in large pots (2ft wide and deep terracotta)? In Scotland!
i would use John Innes no 3 loam based compost.
Ordinary multipurpose potting compost is far too fibrous and light for permanent planting of shrubs.
Thank you - I will do! Should I use grit in the bottom of the pot?
I agree JI. No.3, with some grit for drainage.
Whether they can stay in pots depends on type of Lilac; there are some dwarf types, which would be fie, but there are some that will grow far too big for that size of pot.