Q: I recently moved into a ranch house that has a back yard with a 30-by-50-foot slope facing the house. Gardeners used to live here. I’ve been barely able to keep up with the garden work and now would like to change it to something less labor intensive.
There are two pathways up the slope to a small sitting area, plus an arbor at the entrance and a picket fence across the upper area. There was a 40-foot-tall Norway maple that I had cut down, so now the entire garden gets sun. Any ideas on how to revamp this to cut down on maintenance?
A: Cutting down the maple changes the whole complexion of the site, so you may be forced into making changes if shade plants are now exposed to full sun on a bank.
It sounds like you’ve got a nice framework. Without seeing what’s there, it’s hard to say how much you can alter vs. ripping out and starting over. I’d much rather do a “surgical approach” in revamping a landscape rather than a total redo -- unless things are really overgrown and struggling.
Planting on a slope also is a little more difficult than level ground. Soil tends to be thinner on slopes, plus young plants are put under extra stress when they’re transplanted into the intense heat and light of a sunny bank.
That said, there are a few general ideas that can reduce maintenance while keeping the slope looking nice. Most people are tempted to just grass slopes or plant a single groundcover over the whole thing, such as creeping junipers or vinca.
I think a better idea is to pick maybe 5 to 10 different species -- all low-care ones suited for hot, sunny sites -- and plant them in clusters or masses. “Sweeps” of several plants create good-looking patterns and decent variety without the work of dozens of different shrubs and flowers.
I’d also think about layering -- planting taller plants toward the top of the bank, then stepping down to mid-sized shrubs and evergreens in the middle, then adding color toward the bottom with perennial and annual flowers plus a low shrub or two.
Mix evergreen and deciduous plants so you’ll have interest throughout all the seasons.
Some good examples of plants for the top that grow more than 8 feet tall are tall evergreens such as spruce, upright hollies, arborvitae, Leyland cypress, Douglas fir and upright junipers; small flowering trees such as crabapple, Kousa dogwood and goldenrain, and tall shrubs such as lilacs, ninebarks, butterfly bush, viburnums, crape myrtles and tree-type hydrangeas.
Good examples of mid-section plants in the 3- to 8-foot range include evergreens such as blue hollies, dwarf Hinoki cypress, dwarf goldthread cypress, yew and mid-sized junipers; ornamental grasses such as switchgrass, feather reed grass and miscanthus; flowering shrubs such as shrub roses, spirea, beautyberry, caryopteris, dwarf lilac, weigela, Virginia sweetspire and redtwig dogwood, and some of the taller perennials such as helianthus, bearded iris, Russian sage, shasta daisies, tall garden phlox and even a few vines on trellises.
Good examples for the lowest rung include perennials such as sedum, salvia, purple coneflowers, hardy geraniums, coreopsis, mums, catmint, liriope and gaillardia; low evergreens such as boxwoods, creeping juniper and nandina; most any sun annual, and spreading groundcovers such as leadwort, creeping sedum or vinca.
The idea is to pick two or three plants in each of those main categories and plant groups of each.
You’ll have a fair amount of weeding and mulching in the first few years until the plants spread out. Eventually they’ll fill in and touch, lowering the work load. All plants need some care, but most of the ones above get by with just one or two bits of attention per year.