These easy-care perennials may be low-maintenance, but they are high value assets when it comes to creating garden vignettes that will look fantastic in your garden month after month — they give, give, give, and ask for so little in return! All of the perennials on this list will thrive on a well-timed, once-a-year maintenance task. The secret is in knowing what to do, when to do it, and what clues to look for to help figure it out. See below for plant recommendations under one the following maintenance tasks:
- Enjoy the seasonal flow, then cut back.
- Remove old foliage, make way for new.
- Cut down after killing frost.
- Remove last year's foliage to reveal blooms.
- Cut spent blooms off at ground level.
Don't miss the bonus at the bottom of this post: four plant combos that only use plants that will thrive with an annual maintenance blitz. And you can
search the site for even more ideas by filtering for "Once-a-Year-Care" in our plant combo database.
Enjoy the Seasonal Flow, Then Cut Back
The allure of these perennials is in their connection to the seasons as they undergo their annual cycle of growth, bloom and decline. For example, the lush ferny foliage of Amsonia hubrechtii is topped with delicate blue blooms in early summer, but the pinnacle of its performance comes in fall, when its mounding form takes on golden autumnal tones. The dried seed heads of Jerusalem sage, sea holly, and stonecrop are decorative well after the flowers fade and often hang on well into late fall and early winter — a magical sight with a dusting of frost.
I included Japanese forest grass in this section because its grassy foliage is attractive from spring’s lush growth until its tawny remains finally succumb to the ravages of time in early winter. Gently swaying mounds of Japanese forest grass introduce a lovely sense of movement to the garden. Also a grass, but with an entirely different arc of interest, the purple moor grass peaks in late summer and is especially wonderful in fall, when its strictly upright inflorescences take on tawny tones.
And care couldn’t be easier. Simply cut them off at ground-level when they’re no longer pleasing and attractive to you. Just make sure do it by early spring, to make way for the new growth.
Remove Old Foliage, Make Way for New
These evergreen ferns should be cut to the ground when new growth starts pushing from the base. For the Himalayan maidenhair fern, that’s late January, early February in the Pacific Northwest. It's a bit later for the tassel fern -- about late March, when the new fronds are swelling at the base. In both cases, make sure you do it before the new foliage unfurls to avoid damaging or inadvertently cutting the new growth. This might be hard advice to follow, because it may feel a bit counterintuitive, as the plant may actually still look pretty good. But it really is worth it, because it will be rejuvenated with fresh new foliage that is lush and beautiful.
Once you get the hang of what you're looking for, you can apply this maintenance strategy to other ferns you might be growing. Our native sword fern ( Polystichum munitum) benefits from this treatment, for example.
Cut Down After Killing Frost
Singled out for handsome foliage, these perennials contribute to the garden for many months from spring until late fall. But after the killing frost, their garden worthiness is exhausted for the season and they can be cut off at ground level as you put your garden to bed.
Remove Last Year's Foliage to Reveal Blooms
Cut the foliage of these evergreen perennials to the ground before the blooms emerge in order to enjoy an unobstructed view of the flowers. Though the method is the same, the timing is slightly different for each.
The hybrid hellebores begin blooming very early, so plan on cutting away the previous year’s green foliage in December or early January. The Epimedium x rubrum pushes out delicate blooms on thin wiry stems in late March, so cut last year’s foliage to the ground in early March when you see activity commencing at the base of the plant. New foliage will follow the display of flowers and freshen the plant for the new year.
Cut Spent Blooms Off at Ground Level
The bold toothy foliage of the Corsican hellebore looks handsome year-round. In late winter, apple green flowers appear atop stems produced in the previous
year. When the flowers are spent and no longer attractive, cut the flowering stems to ground level. Though I enjoy the blooms, especially given that
they're in color when the offerings are still pretty sparse, they're pretty quick to go over and I'm always a bit relieved when I cut them away to
make way for the fresh new growth that will push from the base. In no time at all, it produces a fresh mound of foliage that will carry the scene until
the cycle begins anew.
BONUS: Combos Happy with Annual Maintenance Blitz
The plant combos below are compositions that ONLY include plants requiring once-a-year care and will thrive on a single annual maintenance blitz.