Perennial Garden Landscaping

Preparing the Garden

• Remove any weeds or grass from the chosen garden area; many weeds are perennial in nature and will return year after year if not removed when you're initially preparing the bed. The garden soil should be well-drained, a must for winter survival. Perennials can suffer more damage from poorly drained soil conditions over the winter than they can from winter temperatures. Add organic material, such as manure, compost or a peat moss and compost combination, to less than ideal soils.

Planting

• Choose plants that fit the site based on light and moisture requirements, mature size, height and bloom time. Perennials purchased in containers can be planted from spring through fall, but early planting will allow time for good root growth. Fall plantings may suffer from frost heaving if the roots have not had adequate time to develop. Container perennials should be planted to the same depth as the container they were grown in; if they're planted too high, the roots will dry out and affect the plant. Water well once the plant is in the ground, and monitor the soil moisture regularly until the plant is well-established. Prolonged dry periods can damage or slow new plant growth.

Maintenance

• Mulch perennial gardens to reduce weed growth and maintain good moisture levels. New beds should be mulched when planted and additional mulch added each spring to maintain a 2-inch depth. Mulching in the fall is not necessary unless perennials have been recently transplanted and need added winter care. Fertilization is not required if the perennial bed has been properly prepared; excess fertilizing can limit the blooms the plant will produce. Deadhead spent flowers, remove any weeds as soon as they sprout and stake any tall plants to prevent them from leaning or falling over.

Dividing Perennials

• Once plants start to overtake the area or get too large, it is time to divide. Most plants should be divided in the spring before the new growth begins. Early-blooming perennials, such as poppies or peonies, are best divided in the fall once the foliage begins to die back. Use a garden spade or fork to dig out the entire plant and remove as much of the soil as possible. With pruning shears, cut the roots apart, creating three to five smaller plants, depending on the size of the original plant. Replant the new divisions, then water and mulch.

Winter Care

• Spent perennial stalks can be left standing over the winter to provide seeds and protection for birds and visual interest in the garden until the spring. The stems also can provide protection to the plant crowns during cold weather, and act as a plant marker in the spring, preventing accidental digging near the plant that might damage the root growth. If you prefer, perennials can be cut in the fall, but not until they have gone dormant for the season. Cut to 2 to 3 inches of the plant crown; cutting too close may damage the new growth that follows in the spring.