Tips for Planting the Perfect Perennial Border

Harmonia Inc’s Roxine Brown explains how she gives gardens an edge.
Perennial Garden And Bluestone Staircase

A bluestone staircase traverses a perennial garden planted with brilliant blue Echinops, white Gaura, and pink coneflowers, alongside clumps of Pennisetum grasses.

HC&G: What’s your favorite location for a perennial border?

Roxine Brown, founder and creative director, Harmonia Inc: In the distance, at a site’s perimeter, which forces your eye to travel and experience the expanse of a property. And in a looser way, perennials are lovely surrounding and softening the edges of a pool patio or terrace, essentially creating a cozier environment.

What’s the ideal spot for perennials?

Most people like them in the sun for visibility, but I love them in the shade, where dappled light can further enhance a beautiful vista. Classic plants such as astilbes, monkshoods, Dicentra alba, and ferns are great in shady borders. In the sun, I prefer to use ornamental grasses for a more beachy look. If you plant them under a few upright Japanese maples, stewartias, or crape myrtles and dot them with flowering perennials like alliums, foxgloves, Gaura, Nepeta, or lavender, you’ll have a gorgeous tableau.

Potted Plants Lining Outdoor Terrace

Crape myrtles add height to a creekside border.

How do you give a perennial border structure? 

It should have layers to it, incorporating areas of trees as well as flowering shrubs, from common hydrangeas to Sambucus [elderberry], especially the ‘Black Lace’ cultivar. Adding perennials to the mix will give you three layers, lending height and visual interest even to a very minimal property.

What are ideal soil conditions for a perennial border?

Always analyze your soil before planting. If you’re located in the woods, you probably have a lot of sand, and if you’re in a former farming area, there’s probably a claypan. Certain plants require specific conditions, so you need to amend the soil accordingly. For sandy soil, add organic compost, and for compacted soil, add both sand and compost to it.

Crape Myrtles Lining Creekside Border

Potted tropicals enliven a terrace.

What mid-to late-summer plants will perk up a border?

White and pink anemones, monkshoods, and mallows, and ornamental grasses for some drama. And add a couple of shrubs, such as Lespedeza, which has a beautiful deep-pink flower in August, and Callicarpa americana [beautyberry], which has an insignificant flower, but pays off with great-looking bright-purple berries in the autumn.

What must-have accent pieces look good in a perennial border?

A favorite sculpture or old vintage urns, and benches and hammocks are nice in especially quiet corners. And a little pergola will serve as a focal point, while also allowing you to experience the garden from a different perspective.

The print version of this article appears with the headline: Border Patrol.
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