Native Vines, Containers and Small Spaces: Native Plants for City Living in Chicago

Native Plants in Chicagoland · Part 7 of 7

Not everyone has a yard. Plenty of Chicagoans garden on a condo balcony, a back porch, a two-flat's narrow side yard or a gangway that sees two hours of sun. The good news is that native plants work in small spaces too, and in a city where green space is scarce, even a few pots on a third-floor balcony give bees and butterflies a place to stop.

This final post in the series covers native vines for fences and trellises, how to grow natives in containers (including getting them through a Chicago winter), and ideas for gangways, side yards and balconies.

Native vines: going vertical

On a 25-foot city lot, the biggest planting area you have may be the chain-link fence along the alley. Vines turn fences, garage walls and porch railings into habitat without taking up ground space.

Two look-alikes to avoid

• Sweet autumn clematis (Clematis terniflora) looks a lot like native virgin's bower and is widely sold, but it's an invasive Asian species that seeds into natural areas. The easy tell: virgin's bower has three coarsely toothed leaflets per leaf; sweet autumn clematis usually has five smooth-edged leaflets.
• Oriental bittersweet (Celastrus orbiculatus) is banned in Illinois and has been mixed up with the native species in the nursery trade. Oriental bittersweet has rounder leaves and berries tucked along the stems; American bittersweet has more pointed leaves and berries in clusters at the branch tips. This is why it pays to buy bittersweet only from a native specialist.

"Near-native" options

A few popular vines are native to North America but not to the Chicago area. Trumpet honeysuckle (Lonicera sempervirens) is native to the southeastern U.S. It's well-behaved here, hummingbirds love it, and it's a far better choice than any Asian honeysuckle. American wisteria (Wisteria frutescens) is native farther south and is a much tamer substitute for the Asian wisterias. Neither is a true local native, but both are reasonable picks if you want their particular look.

Vines and old Chicago houses

Self-clinging vines like Virginia creeper can look wonderful on brick, but they hold moisture against walls, work into old mortar and wood trim, and leave marks when removed. On a vintage home, it's safer to grow vines on a freestanding trellis, a fence or a garage wall a few inches out from the house than directly on the masonry.

Native plants in containers

Natives can do well in pots, but they don't behave quite like they do in the ground. Their roots are confined, pots dry out fast in summer, and roots in a container get much colder in winter than roots insulated by the earth.

Container basics

• Go big. Larger pots hold more water and buffer temperature swings. Many prairie plants have deep roots, so favor tall pots over shallow bowls.
• Drainage holes are non-negotiable. Use potting mix, not garden soil, and consider adding some grit for prairie plants that like dry feet.
• Use frost-proof pots if they'll stay out all winter. Terra cotta and thin ceramic tend to crack.
• Water more than you'd expect. "Drought-tolerant" applies to deep-rooted plants in the ground, not in pots. In July, check daily.
• Skip most fertilizer. A little slow-release feed in spring is plenty; too much makes prairie plants floppy.

Natives that do well in pots

Hanging baskets and window boxes

These are the hardest containers for natives: small soil volume, constant wind and sun, and almost no winter protection. Be realistic. Treat baskets as annual displays, use native annuals like partridge pea, or plant perennials there for the season and move them into the ground or a larger pot in fall. Window boxes do better if they're deep and on a shadier side of the house.

Getting potted natives through winter

Roots in a pot face much harsher cold than roots in the ground. University of Illinois Extension's rule of thumb: choose plants rated hardy two zones colder than where you live. For most of Chicago, that means plants hardy to zone 4 or colder, which describes most true local natives. Then pick one of these approaches:

• Unheated garage or shed: move pots in once they're dormant. The goal is cold but not brutal, roughly 20°F to 45°F. A heated basement is too warm; many natives need a cold rest.
• Group and mulch: cluster pots against a north- or east-facing wall, out of wind and winter sun, and pile shredded leaves or straw around them.
• Bury them: if you have any ground, sink the pots into soil or a mulch pile for the winter.
• Keep them watered: water well before the ground freezes and check during dry thaws. Moist soil handles cold better than dry soil.

Small spaces, big impact

Gangways and narrow side yards

The shady strip between houses is a natural woodland edge in miniature. Plant Pennsylvania sedge along a stepping-stone path, then add native ferns like ostrich fern or lady fern for height, with wild ginger, wild geranium and woodland phlox for spring color. Keep a clear path for garbage carts and meter readers, and leave space along the foundation.

Balconies and roof decks

High balconies are windy and often scorching, which suits tough prairie plants. Choose shorter, sturdy species, use heavy pots that won't tip, and group containers so they shade each other. Before you load up a balcony or roof deck, check your condo association's rules and weight limits; wet soil is heavy.

Front stoops and porches

A pair of large pots by the front steps, each with a grass, a long-blooming flower and something spilling over the edge, is an easy, visible way to show neighbors what natives look like. Swap the summer bloomer for aromatic aster in fall, and leave the grasses standing for winter.

Wrapping up the series

Over seven posts, we've covered why native plants matter, which invasives to pull, when and how to plant, where to buy, and how to use natives in lawns, parkways, vines and containers. If there's one takeaway, it's that you don't need acreage or a total overhaul. A few keystone plants, a strip of lawn turned into a garden, a vine on the alley fence or a pot of asters on the balcony all add up, one yard at a time.

This time of year, the easiest step is the one from Part 1: leave the leaves and the standing stems for winter. Come spring, you'll be ready to plant.

Sources

• The Morton Arboretum, Virgin's Bower
• Illinois Native Plant Society, Plant Profiles: Native Vines & Climbers
• Illinois Wildflowers, American Bittersweet
• Illinois Wildflowers, Trumpet Honeysuckle
• University of Illinois Extension, Overwintering potted plants
• WTTW, Prairie in a Pot: Native Gardening on an Urban Balcony