Shade plants can have a real impact in our gardens. Modern shade gardens are no longer limited to a color palette of dark green. Many species now have extremely colorful foliage and can tolerate our hot, arid climate surprisingly well. Shade plants do require more neutral soil pH levels than are found here in the Central Valley as well as cooler, damper microclimates. But we can lower soil pH levels fairly easily and amend the native garden soil to promote good drainage and water retention.
When planning your shade garden, start by monitoring sun hours on the eastern and northern sides of structures, fences, your neighbor’s house, your garage. No shade plant can survive the scorching rays of summer afternoon sun here. A few hours, two to three, of morning sun, northern or eastern light or heavily dappled shade will provide enough light to help foliage colors develop full and to promote flowering. Be aware that the sun’s angle in the sky changes over the growing season; as the sun moves in a northerly direction in the sky during the summer months, its rays can reach some spots in north-side gardens.
Sulfur helps lower soil pH levels. Feed your shade plants with a fertilizer formulated with extra sulfur, at least 3 percent. A half-cup of sulfur granules for each plant added to amended soil at planting time and again once or twice during the growing season can also reduce alkalinity (common in desert/savannah areas like ours without significant rainfall).
Many shade plants are native to cooler climate zones where the soil is composed of decaying or decayed woody materials such as fallen tree leaves and needles. It’s so important to amend the soil in shady planting beds with composts or humus rich in organic matter and to mulch to control for temperature fluctuations.
Here are a few suggestions for really colorful perennial shade plants for your garden. All are favorite snail and slug snacks and heuchera are also mealybug targets. Lay down iron phosphate snail and slug baits in planting areas, monitor for pest insects and spray with insecticidal soaps when necessary (but not on hot days).
Heuchera (coral bells, alum root) – Although heuchera produce very pretty small flowers on long stalks ( a common feature of flowering shade plants) in spring, summer or fall depending on variety, it’s the very striking foliage color variations (chocolate, red, silver,purple, burgundy) that make heuchera a mainstay in shade gardens. Divide the clumps every few years and replant the sections. Require moderate to medium water. The flowers are attractive to hummingbirds.
Hosta (plantain lily) – Another clumping shade plant with large variegated leaf color. Hostas are dormant in winter and seem to disappear. The older and larger they get, the more intense the foliage color. Medium water, regular feeding during the growing season.
Coleus – The problem with growing coleus in shady planting beds is that their brittle leaves break off easily. They are also frost-tender. Plant coleus in sheltered spots where they won’t be damaged by raking or traffic or in containers. Varieties with more red in the leaf color can better tolerate a little sun. Pinch off flower stalks to keep a rounder, bushier shape. Irrigate to keep the soil moist.
Elinor Teague: firstname.lastname@example.org