Nick Maclaren wrote:

Andy Burns wrote:

I'm trying to figure out what size of trees would need to be planted now
such that they reached approx 3.5m in three years time

It's a rare temperate tree that will put on more than 40 cm of height
a year, and 20-30 cm is more common.

Thanks, that could save maybe 30% by buying one or two "sizes" down, but
it adds up over 50 trees ...