Q.i have a zinfin doll hydrangea, and a buddelia, zone 5 (nh) do i need to COVER them for the winter? or is mulch at base enough..?
I’m new to this, don’t want to kill them by covering, but don’t want them to perish in the cold winter up here…I have bushel baskets, and have read to lay a good cover of mulch at base..but should they be covered, or will that kill them..? thanks.!
Your hydrangea and butterfly bush are hardy. However, butterfly bush dies back so part of winter prep is to cut all stems down to 9-12 inches. Don't cut back the hydrangea; in spring you can cut it back by 1/3 if you like. Put 2-3 inches of loose mulch, wood chips, chopped leaves or straw, over the roots. No other winter prep is required except watering the plants if autumn is dry.