How I grew a prairie on my balcony—and how you can, too

City spaces may seem limiting when it comes to plants, but even a small balcony can become an oasis. When we moved into our condo, I turned our 5-by-10-foot balcony into my personal green space, where I can de-stress and enjoy my little piece of “Horto in Urbs.”

Although there are more than 400,000 plant species worldwide, I know only a subset will survive in Chicago, especially over winter. But I also know there are more options than the common store-bought showstoppers seen throughout the city. As a self-identified plant nerd, I wanted to try to grow a native Illinois prairie on my balcony—so I set out 15 years ago to make it happen.

The challenge? 
Figuring out how to grow wild, deep-rooted prairie species in shallow containers in the middle of a concrete jungle.

The Pot Struggle is Real

First hurdle: winter. 
Chicago winters are no joke, and pots are a tough environment for roots compared to deep and insulated prairie soil. I felt I had to be choosy with materials, knowing terracotta and brittle plastics can crack in the cold. I landed on fiberglass, and later tried steel and concrete, which I don’t recommend for balconies unless you want to test your weight limits. Deeper pots are better—mine are at least 16 inches deep—and I always try to insulate the sides to protect roots from freeze-thaw cycles; I use pieces of styrofoam.

Getting Soiled

Next up: soil.
Illinois prairies vary based on the soil they grow in; sand prairie plants are very different compared to wetland plants. I knew I couldn’t totally recreate the complexity of prairie soils, but I tried to mimic them the best I could. I used commercial potting mix as a base and tweaked each pot to simulate different habitats, adding peat for wetland species, sand for dry prairies, even rubber bits to mimic gravelly slopes. Did I overdo it? Probably. But it was fun. In hindsight, a good potting mix would suffice for most plants. But if you want to mix it up, there are some lightweight amendments which can be added to make your soil hold more water (peat), keep it drier and more aerated (perlite), or both (vermiculite).

Plant Picks

With pots prepped, it was time for the fun part: choosing plants.
I looked for species that matched my conditions—mostly full sun, good drainage, and, because life happens, some seasonal neglect. Native tallgrass prairies are famous for very tall plants, some almost 12 feet tall. I skipped the tallest prairie species and anything too aggressive. My goal was to mix plants that were attractive, hardy, and would play well together in a confined space.

I picked species from habitats like sand prairies, wetlands, gravelly slopes, and savannah edges (a sunny forest edge). In addition to anything too tall for a pot, I avoided forest plants, since they require shade—something my south-facing balcony was lacking. I wanted beauty, resilience, and biodiversity, all in a container garden. After 15 years of experimenting, here’s what I’ve learned:

The MVPs: Most Valuable Plants

Through lots of trial and error (and meticulous note-taking, because: scientist), I’ve found some real winners.

Some species surprised me—like fringed loosestrife (Lysimachia ciliata), which was both beautiful and a bit too enthusiastic. Others, like wild indigo (Baptisia) and lobelias, failed to thrive but taught me valuable lessons about plant needs, microclimates, and container life.

What I’ve Learned

A few broad takeaways (which, let’s be honest, still need testing):

• Plants that reseed themselves and come back each year are great. They act like well-behaved annuals.
• It seems like fibrous or rhizomatous roots overwinter best in pots; tap roots, not so much.
• Some plants can act as “nurse plants” (such as sedges) and protect plants growing near them, improving pot survival by stabilizing soil and providing winter cover.
• More native species can handle container life than I originally expected.

One of the ongoing mysteries for overwintering plants:
Does keeping the soil wet in the winter help or hurt with freeze-thaw damage? Some say wet soil freezes more slowly, while others claim that drying out soil in the fall can reduce damage. I’m still figuring it out—but leaning toward dry.

Phlox (P. bifida and P. divaricata)

In the End

Gardening is experimentation.
Some plants will fail, and that’s okay. Others will thrive and surprise you. What matters most is creating spaces that invite life—birds, bees, and a little biodiversity—back into our urban world.

If you're a fellow frustrated botanist, or just a curious gardener, I hope my balcony experiments inspire you to try some native plants in your space. Start small, stay curious, and don’t be afraid to fail. The plants, and the pollinators, will thank you.