Anju Lucas, perennial expert at Edwards Greenhouse, is enthusiastic about Hydrangeas paniculata because they grow so well here, and bloom on new wood, which means that you can prune almost whenever you wish. Most folks prune these hardy perennials in spring to control growth that can become ungainly. A small version is called Bobo, but the larger H. paniculatas that impress her include Zinfin Doll and Fire Light, and they can quickly grow tall.
Hydrangeas grow best if there’s light shade available, and ample water.
Lucas said they also have some new Clematis from Proven Winners, including Pink Mink, Happy Jack Purple, Jolly Good and Brother Stefan, the latter vivid blue with yellow stamens.
Clematis also grows well in our soils, but it’s a good idea to plant them deep to prevent Clematis wilt, that can kill or drastically set back your new vine.
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This weather has been cold enough to curl your rhododendron leaves, hasn’t it? Before we added onto our house, we had a Viburnum whose leaves curled slightly or a lot, so we could practically tell the air temperature by looking at the Viburnum leaves. You may be able to do the same with rhody leaves.
Plant leaves move because of light intensity, light direction, water availability and temperature. The latter movement diminishing leaf surface is termed “thermotropic.” In desert conditions, leaves usually turn upward and curl to avoid too much light intensity. Rhododendrons and some Viburnums curl and tend to droop when they are too cold. Covered with snow, they’re a bit insulated, so don’t curl quite so much.
Viburnums are available in many different configurations and blossom structures, and they grow here easily and very well. When we first bought this house we had four Viburnums in this yard including American cranberry bush, leatherleaf, Korean spice, and a snowball bush.
They thrive even in low water conditions.
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If you’re new to this area, please do NOT put fireplace ashes on any of your garden beds. They would raise the pH or alkalinity of your soil, and our natural soil is very alkaline to start with. Most gardeners work hard to lower that alkalinity because most ornamentals and vegetables grow their best at a pH of 6.5 to 7.0. Our native soils’ alkalinity is higher than 7.0 in nearly all locations in this valley.
If you’ve moved here from the Middle West, our winter is not surprising you, but we’ve not had this much snow cover or prolonged winter cold in this valley for over 30 years. We like heavy snows in the mountains, for that’s the source of our water. It also provides snowy slopes for sledding, snowboarding and skiing for Idahoans and tourists who leave dollars in this state. Many of us do not love snow in the valley, where it interferes with school schedules and traffic and pedestrian movement.
Send garden questions to firstname.lastname@example.org or Gardening, The Statesman, P.O. Box 40, Boise, ID 83707.