In The Garden May 2017

By Peg Keeleyside

It was a wicked cold wet winter here in the Pacific Northwest, and my garden shows it.

The big rosemary plant I had sheltered near my dryer vent is a goner. So is a large New Zealand flax with its big spiky leaves. These and many other just-hardy perennials – the ones that can’t handle subzero temperatures for the long spells we had – are all done for.

Reflecting on the damage this past winter has wreaked, I’m reminded that climate change isn’t just about the higher temperatures and summer droughts that we’ve had, it can also mean more severe swings in winter weather conditions too.

To get some supporting data on how our weather is changing, the U.S. globalchange.gov website used to have links to a variety of projected climate change models for U.S regions you could access online. I’ve used these in past columns.

Those links have been taken down by the Trump administration, and the public’s climate science inquiries – like how much of a swing in our summer to winter temperatures we can expect in our gardens – or in our farm fields – in coming years, will have to be sourced elsewhere on the Internet than on government sites.

My point? Well, apart from the dubious project of climate science denial, if you’re thinking of buying an expensive specimen tree, or landscaping a new garden, you’re likely going to want to know if your trees and plants can survive the projected colder, wetter winter conditions for our area.

Our current plant hardiness zone, Zone 8–9, has historically been no more than 14 degrees F in the winter months. However, planning ahead, it might be that we should start looking at trees, shrubs and perennial plants that withstand Zone 7 winter conditions; as much as 0 degrees F.

If you want to find out more about the USDA plant hardiness zones, visit the garden.org website where there are good color-coded visual maps.

And when you’re shopping for plants, take a moment to check the growers tag for zone compatibility. If you purchase a Zone 9 compatible plant, keep it in a pot so you can bring it inside over winter.

Moving on to some plant picks to look for at the garden centers this month, the trend in both annuals and perennials for flower color is to a more muted color palette_say pale apricot over bright orange flowers. You will also see lots of cool foliage perennials where leaf shape alone plays the central role.

Calibrachoas and supertunias, both with small repeat blooms lasting much of the summer, are great picks for baskets and containers. Pair them up with a cascading bright green-leafed ipomoea (potato vine) for a really abundant look.

Looking for a climbing vines to cover a fence or trellis? Try an evergreen clematis like Armandii Apple Blossom, which is hardy to Zone 7. It flowers dark pink turning to pale pink star-shaped blooms in March and April. As a bonus, it’s fragrant.

The trend in shrubs is for new dwarf versions of lilacs, hydrangeas and buddleias. Look for the “Bobo” cold hardy mini hydrangea with its white flowers that turn pink in autumn.

The new miniature buddleias with their long stems and bottle-brush blooms are way better behaved than their regular size counterparts and come in both the lavender and pink.

Garden center finds this May are also perennial plants with dark burgundy-colored foliage. Look for the low-growing sedum called “Firecracker.” In hucheras, look for a new hybrid variety series, “Foamybells,” which starts off with bright green leaves that turn burgundy in the fall.

Gardeners and garden lovers looking for a day of inspiration this summer should check out the South Delta Garden Club’s 2017 Garden Tour happening on June 25 in Tsawwassen and Ladner.

There are 10 great local gardens on the tour and advance tickets are $15; available at local Delta garden centers starting this month. Visit the club website at southdeltagardenclub.ca for more information.