painting new roughcast

[fmck]

I just finished the next stage of my garden wall {mini project while waiting my loft BW}
My mrs wanted roughcast/wetcast to the wall to match the house. I had never wet cast before but got there in the end. The start is a bit lumpy but sure it wont be noticable once painted.

I obviously would like to start painting but dont know when. Do you wait a month for the full initial strength or just paint when grey?

Cheers