Define 'shade' before planting a shade garden

One of the toughest tasks in gardening is dealing with the dark side: coaxing plants to grow where the sun won't shine.

But the challenge is worth it. Shade gardens can introduce many subtle colors and varying leaf textures to otherwise barren parts of the landscape.

First, though, define darkness. Just how shady is it where you plan to plant?

Measuring daylight is an inexact science. Even the experts don't always agree about how to quantify light levels, which are divided into as many as seven different categories, from full sun to deep shade.

"A common sense filter has to apply here," said Renee Shepherd, founder of Renee's Garden Seeds in Felton, Calif. "There's light shade and full shade, afternoon shade and morning shade. Under one kind of tree you might have extreme shade; under another it may be dappled."

Above: This photo shows bleeding heart. Below: This photo shows Virginia bluebell in a woodlot in New Market, Va. (Dean Fosdick ~ Associated Press)

Finding the right location can mean life or death for a plant that needs some degree of sunlight to grow and reproduce.

"Vegetables that have foliage, like greens -- lettuce, spinach and the cold crop family -- can get by with four to six hours of direct sun," said Keith Hansen, an extension horticulturist with Texas AgriLife Extension Service, in Smith County. "But anything that produces fruit needs light -- the more the better."

You can meet most light intensity challenges by:

* Pruning. Thin out thick stands of trees to reduce competition for nutrients and sun. Cut away branches that block sunlight. "Trees can be thinned, lower limbs can be removed. But that's a temporary fix," Hansen said. "They'll continue to grow and cast more shade. Find plants that match the circumstances for the proper long-term remedy."

* Amending the soil. "You don't want to put too much mulch down or you'll smother the roots," Hansen said. Compost can help retain moisture and insulate plant roots.

* Going natural. If native plants such as ferns, lily of the valley and Virginia bluebell can grow despite being shaded by trees in the wild, then they should survive similar conditions in your yard. "Think native plants. Think native grasses," Hansen said. "If we can deal with what we have and enhance it, chances are it will work."

* Watering: "Working hummus into the soil or laying a soaker hose, with its tiny perforations that leak moisture slowly and steadily, will create conditions where many plants will thrive," said Graham Rice, author of "Planting the Dry Shade Garden" (Timber Press, 2011).

You need not sacrifice bright colors when installing a shade garden. Impatiens, bleeding heart, geranium (cranesbills) and Lobelia can have eye-catching blooms. And don't forget bulbs: Daffodils and crocuses bloom in early spring, well before the leaf canopy develops overhead.

Foliage also is an important fixture, providing color and interest much longer than flowers, Rice said.

"Bringing together evergreens with different leaf shapes and textures, from glossy spotted laurel to bold Bergenias [elephant's ears] to lacy ferns, ensures that the dry shade garden is always attractive," Rice said.

And don't be in a rush to cut down shade trees, Hansen said. "Be thankful for the cooling benefit your trees provide. Without it, your electric bill would be substantially higher."