When i encounter a big asteroid with good stats, i usually grow all dyson trees and then use my saved up flowers to upgrade everything immediately. But i think ive never seen flowers grow on already upgraded trees. Does anyone know? Bc if they dont grow on upgraded trees, the best strategy would be to first let the trees mature to see if they grow flowers, then harvest the ones that did grow and only then upgrade the trees... My playstyle is to ignore defensive trees and maximize flowers and upgraded seedlings