Pruning hydrangeas is not one size fits all

Q: I have a big leaf hydrangea that blooms blue. It’s old and fairly large. This year it did not bloom at all, so should I still wait until spring to prune? Ironically, I have a white hydrangea that is smaller, and it had its best blooming season ever this summer with extra-large blooms. — Meg Perry, Smyrna
A: The reason your blue blooming hydrangea has not flowered is because you are pruning in spring. Its flower color points to it being Hydrangea macrophylla. This species makes flower buds on last year’s growth, so you cut them all off by pruning in the spring. The white blooming hydrangea is likely Hydrangea arborescens or H. paniculata. These hydrangeas make flower buds in late spring, so pruning in early spring is fine. For more detail, see bit.ly.GAhydrangeas
Q: I have an old, tall, pine that has moss circling around its base. Should I try to remove it or leave it alone? — Jan Wever
A: I’m not a moss expert, but your moss looks like pincushion moss. It’s a common, attractive, clump-forming moss. It feeds on sunlight, moisture and minerals it absorbs from whatever it is growing on. It does not harm anything I can find. I think it’s growing at the base of the pine because the environment is highly organic, with plenty of dissolved chemicals that wash down the bark. I have even seen soap suds at the bottom of pine trees, because some of the things that come down are saponins that behave like soap. I don’t think you need to remove the moss.
Garden questions? Send them to Walter at georgiagardener@yahoo.com. Questions with good pictures, if appropriate, are preferred but not required.

