These Frost-Resistant Plants Add Instant Color to Your Outdoor Containers

For most of the country, the garden palette changes as the temperatures drop. The gold, green and crimson colors of fall fade away, and winter brings on muted shades of brown, white and gray. Bare branches and dead or dormant plants make everything look drab and dreary.

Why Use Frost-Resistant Container Plants?

You don’t have to wait until spring to brighten up the view outside your windows again. Outdoor containers filled with frost-resistant plants add instant color, textures and interesting forms. If your ground is already frozen, look for pre-planted containers. If your climate is mild and the soil in your planters is workable, add plants to existing containers (although it’s better to start them in early fall, so they develop strong root systems). If you can't dig, simply drop the potted frost-resistant plants into frost-resistant, weatherproof containers.

Five of the Best Frost-Resistant Plants for Containers

Boxwoods

Boxwood shrubs (Buxus) are classic choices for adding structure to containers. ‘Sprinter’ (Buxus microphylla) has glossy, evergreen leaves, an upright growth habit and thrives in sun or shade. Deer usually leave it alone. This improved form of a boxwood container favorite, ‘Winter Gem,’ is hardy in USDA Garden Zones 5 to 9. Give it soil that drains easily and wait until spring to apply a slow-release fertilizer. It doesn’t need much pruning, but you can trim it in summer if desired. ‘Sprinter’ grows and spreads 24 to 48 inches high. Its bright green foliage makes a great backdrop for other, more brightly-colored frost-resistant plants.

Pansies

Pansies (Viola × wittrockiana) come in almost every color you could want, and they’re ideal for tucking into containers around taller plants. Let trailing pansies cascade over the edges for a feeling of movement or to draw attention to other plants in the garden or containers around them. Pansies like indirect sunlight and moist, well-draining potting soil and should be mulched to protect their roots and keep the soil from heaving (rising and falling when it freezes and thaws, which can push the roots out of the ground). Water them deeply before a hard freeze, or cover them with frost cloths or pine straw for protection from weather extremes. These short-lived perennials are hardy in Zones 3 to 8, but they’re usually treated as annuals because they become leggy and flowering slows down in the summer.

Heucheras

For texture and color, it’s hard to beat coral bells (Heuchera spp). Most are hardy in Zones 4 to 9 and grow 6 to 18 inches tall with a 12 to 30-inch spread. They usually behave like evergreens or semi-evergreens in Zones 8 to 9, but their tops—that is, their foliage—can turn brown, die or look worn in the colder Zones, 4 to 7. They have a mounding growth habit, prefer bright or dappled shade and are available in a range of striking colors, leaf patterns and leaf shapes. As a bonus, very small flowers appear on thin stems from late spring into midsummer or fall. Another bonus: the leaves of some varieties, like 'Fall Festival,' shown below, are different colors on the tops and bottoms. Don’t plant coral bells deeply; leave the crown slightly above the soil.

Hellebores

Sometimes called Lenten roses (H. orientalis) or Christmas roses (H. niger), Hellebores (Helleborus spp.) are easy-to-grow perennials in Zones 3 to 9. Their nodding flowers can open even in late winter or early spring snow. Most varieties keep their leaves all winter, but in cold regions, the foliage can look ragged until new growth begins. Hellebores need rich soil that drains easily and large containers for their deep roots; avoid transplanting, which stresses them. Give these plants plenty of sun in the winter and spring and some shade when the temperatures rise. If the flowers on your plant face downward, try elevating your container for a better view. Newer hybrids like 'Merlin' have outward facing blooms, and some have doubled flowers.

Ornamental Kales and Cabbages

Frost-resistant vegetables like these add shades of pink, green, creamy white and purple. Ornamental kales and cabbages (Brassica oleracea) colors become deeper and richer in cool weather, especially after frost, but their leaves can get mushy when temperatures stay at or below 10 degrees F. for a long time. If a prolonged hard freeze is expected, cover the containers or move them to a protected spot. These ornamental veggies take full sun but need some afternoon shade in warm regions. Mix them with hardy cyclamen, pansies and violas, or let the smooth-leaved cabbages contrast with the frilly-leaved kales. These are fast-growing, cool-season biennials that produce leaves in their first year. In their second year, they send up rather ungainly flower stalks that some gardeners remove. Others simply replace the entire plants. These plants mature at 12 to 18 inches wide tall and wide and are hardy in Zones 2 to 11.