by Jan Cashman
During this time of the year, I am glad I have lots of perennial flowers emerging in my beds. Planting a lot of annuals every spring is time consuming. After reading articles in gardening magazines, consulting our wonderful staff, and visiting a botanical garden with a huge and beautiful perennial border while on vacation, I came up with twelve hints to help you create a spectacular perennial border:
- Make sure your border is wide enough. Six to eight feet is minimum for most borders. Any less and it will look skimpy. A clean edge between your border and the grass is nice, but grass will creep in. Landscape edging can help keep the grass out. Black vinyl edging is easy to install and relatively inexpensive. Aluminum and steel edgings are less visible. Or be creative with a rock or brick edge.
- A border needs a background. A fence, the rail of your deck, a stone wall, a row of evergreens, even your house or garage wall can provide a backdrop for your flowers.
- Start with good soil. The best way to do this is to mix organic matter into your existing soil-compost, composted manure, or peat moss.
- Consider the exposure of your garden. You’ll need to choose different plants for sun or shade.
- Don’t plant in straight lines. Curve the edge of your border to give it a natural look. Don’t plant your flowers in straight lines, but plant relaxed, gently curved masses of 3 or more of each flower.
- Plan for four seasons of color. Tulips, crocus, daffodils, and hyacinth bulbs are planted in the fall for early spring blooms. Find out when different perennial flowers bloom; then choose for blooms in spring, summer, and fall. Winter interest can be achieved by adding evergreens to the mix, leaving ornamental grasses standing all winter, and planting shrubs with colorful twigs such as red twig dogwoods. A large border can contain all the colors on the color wheel in various arrangements. For a smaller border, pick a color scheme from your favorite colors.
- Focus on foliage. Strap-leafed plants such as tall ornamental grasses and iris add a vertical dimension among plants with mounded shapes. Intersperse plants with large leaves like ornamental rhubarb. Variegated foliage adds interest. Don’t forget to use plants with colorful leaves like those I mentioned in last month’s article.
- Consider the shape of the plant. I like the looks of plants that grow in small, round clumps. But a garden with only round clumps of flowers is too much of the same thing. Intersperse them with upright plants, sprawling plants, and maybe some pyramidal shapes. Different flower shapes can add interest to your garden; the huge round flowers of giant allium stand up above its foliage. Spiky flowers such as delphinium and salvia have vertical lines.
- Tall plants don’t have to be planted in the back. They can be staggered in the middle areas of your border, especially if they are see-through plants whose flowers stand up above the foliage.
- Add some annuals. The first year or two after planting, before your perennials mature, plant annual flowers to fill in spaces. Most annuals bloom all summer, so they will add color to your perennial border during times when perennials are not blooming.
- Evergreens, roses, shrubs, and ornamental grasses make your border more interesting. Dwarf evergreens such as globe blue spruce add a different color and texture to your border. Bright green dwarf Alberta spruce can add a pyramidal shape. Many newer shrub roses are compact enough to fit in your border. They have striking flower colors, mostly pinks and reds, are fragrant, and many bloom all summer. Dwarf red leafed barberries, spireas, and ninebarks can add color with their leaves. Ornamental grasses add texture and winter interest. Some have variegated leaves.
- Once you plant it, don’t forget it. Adequate water has been especially important for plants these last few hot summers. I fertilize my perennial gardens once in May, when the perennials are emerging, with a small handful of slow-release, well-balanced fertilizer around each plant. Weed control can be a challenge. A 2 to 3 inch layer of soil pep (ground up bark) surrounding the plants holds moisture in the soil, retards weed growth, and makes the weeds that do come up easier to pull. Don’t be afraid to thin or cut back perennial flowers that are overgrowing their spaces or popping up where you don’t want them.
Use these hints to avoid common mistakes and help you create a beautiful and colorful perennial border with accents of grasses, shrubs, evergreens, and annuals.