Happy Urban Dirt

Not all flowers serve pollinators equally. A garden full of hybrid roses and ornamental varieties can look impressive and offer very little to bees, butterflies and hoverflies. The difference comes down to plants that are bred for their appearance versus plants that have evolved with the insects that depend on them.

Why native plants matter

Native flowers and local pollinator species have evolved together for thousands of years. The structure of flower petals, flowering time and the chemical composition of nectar and pollen are matched to the insects that visit them. Take away this match and the garden will become largely decorative from the pollinator’s point of view.

Many popular garden plants are grown for their visual value. Double-flowered varieties are a common problem. The extra petals that attract gardeners physically block access to pollen and nectar. The bee can’t come in.

The numbers behind the decline in pollinators are clear. Study published in PNAS led by: NatureServe and the Xerces Society found that more than 22% of native pollinators in North America are at increased risk of extinction, and 34.7% of native bee species are among the most threatened. In most regions, habitat loss is the main cause. The Xerces Society estimates that native pollinators contribute approximately $3 billion annually to U.S. agriculture, supporting more than 100 crops that depend on or benefit from their work.

What flowers to plant

A mix of native species will serve pollinators better than a single variety. The right choice varies by region, but several species perform well in a wide range of growing zones in North America:

• purple coneflower (Echinacea purple): one of the most recommended native species for pollinators, blooming from mid-summer to autumn and supporting bees, butterflies and goldfinches
• Black Eyed Susan (Rudbeckia hirta): long-blooming, drought-resistant, and found throughout most of North America
• Wild bergamot (Monarda fistula): a favorite species of bumblebees, bees and hummingbirds in most of the United States
• Legume herb (Asklepia tuberosa): a species of milkweed and an indispensable host plant for monarch butterflies, as well as a key source of nectar for many species of bees
• Goldenrod (Solidago spp.): a critical late-season forage for migrating monarchs and dozens of bee species, despite its neglected reputation for causing hay fever

For region-specific plant lists, the Xerces Society publishes for free regional guides covering every part of the country.

First steps without a vast garden

A wildflower bed doesn’t have to be vast to be useful. Pollinators will travel in search of food, so even a container of mixed native species on your balcony contributes to the local habitat.

Seed printingA fourth-generation, family-owned printing company based in Leicester, England, presses wildflower seeds into sheets of handmade recycled paper. The paper is planted directly in pots or beds, watered and decomposed in the soil as the seeds germinate. Although their seed mixtures are selected from native British species, this approach has attracted the attention of gardeners around the world as a way of removing the friction that puts people off wildflower gardening.

Tom Willday, the company’s founder, says the main barrier is friction.

“One of the barriers is that it can seem more complicated than just planting,” Willday says. “Most of it removes the seed paper. You put it in the ground and water it. There’s nothing to store or measure.”

For U.S. gardeners who want to apply the same principle to locally native seeds, seed paper products containing North American wildflower blends are available from several domestic suppliers.

Deadline and conditions

Spring is the most reliable time to start wildflowers from seed in most of the United States. Many native species can be sown in slow autumn for spring germination in northern zones. Most prefer open, low-fertility soil: heavily amended beds favor vigorous grasses and weeds over wildflowers.

Water regularly in the first weeks. And resist your cleaning instinct: this messy structure is exactly what pollinators need.