Key to a Successful Garden: Plant Flowers That Thrive on Neglect

“Can be invasive.” That horticultural description is a recommendation for the type of gardening I’ve been doing for more than 35 years in the St. Louis, Mo., area. That is, I concentrate on easy-care, “you can’t kill ’em” plants. This is a personal list, gained from experience gardening in the U.S. Department of Agriculture Hardiness Climate Zone 6 (bordering on 5).

Some Bulbs are True Perennials, and Some are Not

“They come back every year,” claim the catalogs. But if you live in the middle of the United States, tulips will break your heart. I once planted 100 tulips, of all colors, meant to bloom from early spring through late spring. They did, the first year. But within three years, the bed had bare patches filled only with violets and far fewer flowers on the surviving plants. After decades of trying, I admit that in my climate at least, tulips are annuals.

Daffodils, on the other hand, will grow even on empty lots that haven’t had a house on them for decades. They are the featured flower in an “Operation Brightside” project to beautify the hillsides flanking the highways going into downtown St. Louis. Every spring these hillsides are covered with yellow and white glory. All planted by teenage workers one fall and then replenished every few years.

Other bulbs that are true perennials, once established, include some hyacinths and most crocuses.

Day Lilies, Iris and Other Plants that Thrive in Your Neighborhood

Day lilies (Hemerocallis) and iris are two flower types that you cannot kill once they’re established. I’ve seen bearded iris so hardy they would grow on an asphalt driveway.

Day lilies, too, will grow about anywhere. The house painter who put his ladder in a bed of day lilies by my front steps assured me he couldn’t harm them. He was right. They came back the next year — with more flowers. Day lilies, especially the common orange variety, respond well to stress.

Many gardeners have plant swaps. What grows well in your neighbor’s yard may grow in yours as well. Some other examples of plants that thrive on division: hens and chicks (Sempervivum tectorum), hostas, blanket flower (Gallardia), tick seed (Coreopsis), evening primrose (Oenethera), periwinkle (Vinca).

Volunteers: They’re Not Weeds If You Grow Them on Purpose

What’s the difference between a wild flower and a weed? Location. In the woods, a flowering plant is a wildflower. To some gardeners, any unintended plant is a weed. But when something pops up in your garden that you didn’t plant, it doesn’t have to be a weed. If you decide you want it, it’s a volunteer.

Violets are an example. They can be annoying in a lawn or a tidy flower garden. But they can be great ground cover. I started a tree ring around a Japanese maple; I planted crocus and some perennials from a local nursery. Violet volunteers quickly took over the shadier spots.They choked off ugly weeds and provided a good cover for the crocuses, which, of course, died back after they flowered.

Any flowering species you see growing through the cracks in a sidewalk or by the side of the road — seek it out. I’ve seen cone flowers (Echinacea) and brown-eyed susans (Rudbeckia) growing alongside train tracks. That’s my definition of hardy. The first such hardy wildflowers in my yard just appeared. Some I let stay; other volunteers I’ve transplanted.

You don’t have to wait for volunteers of course. You can buy rudbeckia or cone flowers in catalogs or nurseries.

Warning: Invasive Plants Don’t Play Nice

Of course, you do have to be careful about certain invasive plants. My tree ring ecology was just about balanced — the Chrysanthemum pacifica (the only chrysanthemum that will grow in partial shade) was spreading nicely, the violets grew in the shadiest part, the bulbs bloomed and then faded — when I introduced a couple of vinca vines into the ring. Within a year, the vinca had squeezed out the pacifica and became a vicious weed that was difficult to remove. Even the violets gave way. Oddly enough, my efforts to establish vinca under a large gum tree (where nothing grows) were much less successful.

My lesson from that experience: Be careful what you plant in a small space that you’re trying to balance with several kinds of plants. Unless you want only the most aggressive to win, don’t pit them against other flowers in a small arena. It’s kind of like turning the lions on the Christians.

So put the lions — vinca, day lilies, iris, ground covers and other aggressive, invasive plants — in their own space in a flower bed, not interspersed with other plants. It’s easier to clip the edges of such areas than to watch over individual plants.

Survival-of-the-Fittest Garden Spots

Some areas are suited to a Darwinian approach. I have such a space between the garage and the neighbor’s fence in the back yard of our new home. It was a weed patch with woody tree saplings. So when I had tree work done, I had them grind out the stumps of the weed trees. Then crab grass and other weeds took over.

It’s a perfect spot for a “grow or die” approach. I’m going to set my lions on those weeds.

I’ve planted cone flowers and some bronze ornamental grass (to distinguish it from the weeds) and transplanted a couple iris and day lilies from our former garden. But the weeds are still stronger. So for the next planting season, I’ll transplant some of the primroses that are beginning to outgrow their space in the front. And I will put out an online request for free day lilies, iris and other invaders worth sharing. Whatever I get, I’ll plant lovingly and tend sporadically. Any plants that survive a winter of neglect and look good get to stay.