Hello all: I planted “Bombshell” hydrangeas in November and now I’m excited to see them grow! My question is do I cut the hydrangeas back all the way or do I just leave them be? And do I cut my Carex elata “Aurea” grasses back all the way also? Like just trim them to the ground?
Any insight would be appreciated as to how far back and when (or if) I should trim these.
Thank you so much.
‘Bombshell’ is a variety of Hydrangea paniculata, also known as hardy hydrangeas. H. paniculata blooms on new growth, so any pruning should be done in fall, winter or early spring to avoid cutting off the new flower buds. However, it doesn’t require a lot of heavy pruning. Certainly, you should prune back any dead branches each year, or any branches with unfavorable structure, such as branches that cross over or rub across other branches. After the plant is three or more years old, you may want to reduce height or thin it out by pruning back no more than one-third of the tallest or oldest branches each year to the base of the plant. You can review an answer to a similar question here for more guidance on pruning H. paniculata.
Although it closely resembles many types of grasses, Carex elata is member of the Cyperaceae family and is actually a sedge. Like grasses, Carex elata can be cut right down to the base in the winter or early spring before new shoots appear.
Enjoy your new plants!