Fall evokes harvest time, but it also offers ideal growing conditions for just-planted perennials.
Fix Design Flaws: Do you have a garden bed in need of additional color or has a gaping hole in the center? Now is the time to remedy those issues with perennials.
Time it Right: Plant perennials about mid-September to give them time to establish roots before freezing begins.
Past Prime Bargains: Expect to find perennials at 50 percent or even 75 percent off of regular prices. It’s fine to buy plants that look down and out. If there is still some green, no disease and a great price, give it a shot.
It’s All in the Roots: Frost will kill the tops of your new plants, but it won’t affect the root growth. The roots will grow until the soil freezes solid, which is often weeks or even months after the first frost hits. Water weekly until frost.
Mulch Protection: Once the soil freezes hard, spread a few inches of mulch around the perennials to keep them from thawing, so they don’t “frost heave” out of the soil and expose roots.
Fall Perennial Favorites: Consider aster, astilbe, balloon flower, bearded iris, bee balm, Bergenia, bleeding heart, brunnera, campanula, catmint, columbine, daylilies, dianthus, echinacea, ferns, goldenrod, hosta, lady’s mantle, lamb’s ear, lilies, monkshood, native asters, oriental poppies, penstemon, peonies, phlox, sea holly, sedums and Siberian iris.
Courtesy of the Minnesota Landscape Arboretum