Coloring up your green spaces

If you’re not careful, most of your landscape and gardens will be mostly green for most of the year, and that’s just not very interesting.

Flowering trees and shrubs tend to bloom in spring for a week or so, then it’s over. Perennials for the most part have a bloom period of just a few weeks. Annuals are a way to get color into the garden throughout the year, but most are low-growing, many have been selected for bright, some might say garish, color, and they need replacement every year.

There are always exceptions, of course. Reblooming roses like grandifloras and floribundas will help keep color in your garden through the summer. Among perennials, Russian sage (Perovskia atriplicifolia), coreopsis ‘Moonbeam’ (Coreopsis verticillata), daylily ‘Happy Returns’ (Hemerocallis hybrid) and several others have an extended bloom time.

But for a reliable and easy way to alleviate all that green, we need to think like a Japanese gardener for a moment. Not just for plant choice, but for the Japanese garden’s ability to look interesting without relying on riotous flower color.

The Japanese do it by mixing different shapes, textures and foliage colors. For instance, mugho pine (Pinus mugo) stays low and bunchy and its needle-like foliage contrasts nicely with all the broad-leaved plants in the landscape.

But for breaking up large swaths of uninteresting green, two tactics stand out.

The first is obvious but too often overlooked. And that is to leave some places in the garden unplanted. For a neat appearance, use a good-looking mulch to cover the soil. Nature abhors unused soil, and if sunlight bathes a bare spot, she’ll soon clothe it in weeds. Many garden centers and soil purveyors in Sonoma County sell mulches by the bag. If you want a truckload, call Grab n’ Grow at 707-575-7275.

My personal preference is for about a third of any garden space to be free of plants. This opens up the garden, gives people a place to walk into it and enjoy what’s there up close and personal. It allows a good air flow, lets star specimens stand out on their own, and generally gives a more relaxed and friendly look than a garden crammed to the gills with plants.

The second approach to alleviating a sea of green is to use plants with foliage that’s not green.

Among small- to medium-sized trees, think about the smoke bush (Cotinus coggygria atropurpurea). It has dark, purplish-red leaves and flowers that resemble puffs of lavender smoke.

Many Japanese maples have attractive bronzy-red foliage, including Acer palmatum atropurpureum. Tucked into a shady part of the garden, a Japanese maple will add beauty not only from leaf color, but from leaf shape and the lovely way it displays its branches.

It’s not hard to see examples of myrobalan plum, also known as cherry plum (Prunus cerasifera ‘Krauter Vesuvius’), in this part of California. It’s the medium-sized tree with blackish-red foliage all season, and a specimen in your garden will alleviate a thousand square feet of green.

A dainty version of the cherry plum is the dwarf red-leafed plum (Prunus x cisterna) that grows to 6 or 8 feet tall and as wide, with multiple stems. Red-purple new leaves fade to coppery purple by late summer, but they’re not green and that’s what counts.

Drifts and clusters of perennials that go all green for much of the year need some of their oddly colored cousins for contrast, and a succulent perennial named Aeonium arboretum ‘Zwartkop’ is just the ticket. It produces striking 6- to 8-inch rosettes of thick leaves on rangy stems and their color is almost black. Another cultivar, ‘Atropurpureum,’ is magenta.

Look for the intriguing multicolored leaves of Rex begonias in particular and tuberous begonias in general. Unnamed cultivars are often just as striking as named varieties, so keep an eye out for them in garden centers and nurseries. They’re not hard to find. Similarly, there are a multitude of canna varieties available. But look out especially for “Good King Humbert” with reddish bronze leaves, ‘Wyoming’ with bronzy-purple foliage, and ‘Durban,’ with bright red stripes on a dark purple background that will have people talking.

It’s also good to get some silver-leaved perennials in the garden. The easiest to find is Dusty Miller (Centauria cineraria), with lobed, silver-to-white foliage. Don’t be afraid to cut it back if it gets too loose and rangy. It will soon put out a fresh crop of silvery leaves.

For a small perennial to break up small green-leaved plants, try this common garden geranium: Pelargonium x hortorum ‘Golden Ears.’ Its broad leaves have a large center of bronzy-red edged in chartreuse.

Phormium hybrids are New Zealand natives with fountains of long, sword-like leaves in a wide range of bronze, red and orange colors. They are tenacious growers, meaning that when I went to remove a phormium from my Sebastopol garden, I had to use a log chain attached to my truck. Cultivars to look for include ‘Jester,’ ‘Maori Sunrise,’ and ‘Rainbow Warrior.’ Another phormium species (Phormium tenax), smaller than the hybrids, also has smoldering colors in its leaves. Many cultivars are available.

Don’t forget clumps of grasses and grasslike plants such as Hakonechloa macra ‘Aureola,’ also known as Japanese forest grass. Its yellowish-green leaves make as pretty a picture as you’ll find in your garden, and their color and shape will help interrupt all that medium-green foliage.

Jeff Cox is a Sonoma County-based garden and food writer who can be reached at jeffcox@sonic.net.