Grasses for a Pollinator-Friendly Planting

Ornamental grasses do not attract bees the way flowers do. Grasses are wind-pollinated, so they offer no nectar and no showy petals. Native grasses still belong in a pollinator planting. They give bumble bees and ground-nesting bees places to nest and overwinter. They feed the caterpillars of skipper butterflies and many moths. They hold flowering plants upright and help keep weeds out. In fall and winter, they give seed and cover to prairie sparrows and other birds. The most useful choice is a modest share of clump-forming native grasses woven among native wildflowers.

Do ornamental grasses attract bees?

Mostly, no. Grasses rarely draw bees. A grass flower is built for wind, not insects. The small florets hang their anthers, the pollen-bearing parts, out on thin threads. They release light, dry pollen into the breeze. The feathery stigmas catch pollen drifting past. Because grasses do not need to win over an insect, they produce no nectar, scent or bright color.

Bees do sometimes visit grasses. On still summer mornings, while anthers are freshly open, you may see a sweat bee or bumble bee scraping pollen from a grass seed head. This is opportunistic foraging, and it is not dependable food. In an ornamental border, the grasses that look busiest with bees are often just growing beside a flowering plant the bees are working.

The popular non-native ornamental grasses add even less. Miscanthus (maiden grass), fountain grass and similar garden cultivars give little bee habitat. They host few native insects. Some are invasive in parts of North America. Miscanthus spreads into fields and woodland edges in parts of the eastern United States, and fountain grass invades in the Southwest. Sterile cultivars such as 'Karl Foerster' feather reed grass are tidy and well behaved, but they function mainly as decoration.

What do native pollinator grasses actually provide?

"Native pollinator grasses" are grasses native to your region that support pollinators in ways other than nectar. They contribute in four main ways.

Nesting and overwintering sites for bees

Bunch grasses grow in separate clumps, or tussocks, with small gaps of soil between them. That pattern is good bee habitat. Bumble bee queens often look for sheltered spots at the base of dense tussocks, or in old rodent burrows under the thatch, to start a nest or spend the winter. Most native bees nest in the ground, and many of them dig in the bare, sunny soil between clumps. Dense turf or a sod-forming grass leaves them nowhere to dig.

Food for caterpillars

Native grasses are host plants. A host plant is one that a butterfly or moth caterpillar can eat. Many skippers, the small, quick, orange-and-brown butterflies of prairies and meadows, lay their eggs only on native grasses. Some skipper caterpillars build shelters by folding or tying a grass blade with silk. Adult skippers then pollinate the wildflowers nearby. A planting with flowers but no host grasses feeds the adults but not the next generation.

Structure and support for flowers

Grass roots grow deep, and grass leaves fill the spaces between wildflowers. That makes it harder for weeds to move in. Tall forbs such as coneflowers and blazing stars lean on grass clumps instead of flopping over. In prairie terms, a forb is any non-grassy flowering plant.

Seed and shelter for birds

Grass seed heads ripen from late summer into fall. Sparrows, juncos, finches and buntings eat them. Standing grass gives birds a place to hide from hawks and to get out of the wind. A pollinator planting with native grasses becomes a better place to watch birds in the colder months.

Which native grasses work best in a pollinator planting?

The best grasses for a pollinator planting are well-behaved bunch grasses native to your region. Ideally, the seed or plants come from a nearby source, called a local ecotype. Shorter and mid-height species compete less with flowers, which suits smaller gardens. Tall grasses suit larger prairie restorations. Height ranges below are typical mature flowering heights and vary with soil and moisture.

Grass	Growth season	Typical height	Growth form	Value for pollinators and birds
Little bluestem (Schizachyrium scoparium)	Warm-season	2–3 ft (0.6–0.9 m)	Bunch grass	Host for several skippers; copper-red winter color; seed for sparrows
Prairie dropseed (Sporobolus heterolepis)	Warm-season	2–3 ft (0.6–0.9 m)	Fine-textured bunch grass	Neat clumps leave bare soil for ground-nesting bees; seed eaten by birds
Sideoats grama (Bouteloua curtipendula)	Warm-season	1–3 ft (0.3–0.9 m)	Bunch grass, sometimes short rhizomes	Host for some skippers; suits drier, shorter plantings
June grass (Koeleria macrantha)	Cool-season	1–2 ft (0.3–0.6 m)	Small bunch grass	Early-season structure; low enough to sit among spring flowers
Canada wild rye (Elymus canadensis)	Cool-season	3–5 ft (0.9–1.5 m)	Bunch grass	Quick to establish; nodding seed heads; cover for birds
Switchgrass (Panicum virgatum)	Warm-season	3–6 ft (0.9–1.8 m)	Bunch to spreading	Host for skippers; strong winter cover; can dominate small sites
Indian grass (Sorghastrum nutans)	Warm-season	3–7 ft (0.9–2.1 m)	Tall bunch grass	Golden seed heads; cover for birds in larger plantings
Big bluestem (Andropogon gerardii)	Warm-season	4–8 ft (1.2–2.4 m)	Tall, vigorous	Host for skippers; can crowd out flowers in small plantings

Warm-season grasses grow most in the heat of summer and flower from mid to late summer. Cool-season grasses grow in spring and fall and flower earlier. A mix of both gives structure through more of the year.

Sedges (Carex species) are grass-like plants with triangular stems, not true grasses. They also serve as host plants and ground cover, especially in partly shaded spots where prairie grasses struggle.

How do you add grasses to a pollinator planting?

Treat grasses as the supporting cast and wildflowers as the main food source. Many conservation pollinator mixes lean toward flowers for this reason. The steps below apply to a new planting from seed or plugs.

1. Read your site. Note how many hours of direct sun it gets, how quickly the soil drains after rain, and whether the ground is sandy, loamy or clay. Most prairie grasses need full sun, roughly six or more hours a day.
2. Choose bunch grasses over sod-formers. In small or flower-focused plantings, favor little bluestem, prairie dropseed, sideoats grama or June grass. Save big bluestem, Indian grass and switchgrass for larger areas, where their height and vigor will not swamp the flowers.
3. Source local native seed or plugs. Seed from your region is adapted to local winters, rainfall and day length. Skip invasive ornamental grasses entirely.
4. Read seed amounts as PLS. Prairie seed is often sold and measured in PLS, or pure live seed. PLS is the share of a seed lot that is actual viable seed, as opposed to chaff, stems or dead seed. Many prairie grasses, such as big bluestem and Indian grass, have fluffy, awned seed that clumps together. Mix it with a carrier such as damp sand or sawdust so it spreads evenly.
5. Time the sowing. Many prairie plantings are sown in late fall or winter, called a dormant seeding. Winter freezing and thawing work the seed into the soil, and many wildflower seeds need that cold, moist period before they will germinate. Grass seed can also be sown in spring once the soil warms.
6. Be patient in the first years. Native grasses put most of their early growth into roots. Gardeners often describe the pattern as "sleep, creep, leap": little to see in year one, more in year two, and fuller growth by year three. In the first season, mowing weeds high, above the young native seedlings, keeps annual weeds from shading them out.
7. Leave some bare ground. Keep a few small, sunny patches of soil free of mulch and thick growth. Ground-nesting bees use them.
8. Leave stems standing through winter. Wait until spring to cut back or burn, and cut in patches rather than all at once. Standing grass shelters overwintering insects, feeds birds and catches snow, which insulates the ground.

What can you notice in grasses through the seasons?

Grasses change slowly and quietly, so they reward slow watching. Each season brings something different to look for, at the edge of a garden planting or along a prairie trail.

Spring

Cool-season grasses green up first, while warm-season clumps still look straw-colored. Watch the bases of tussocks on warm, sunny days. Large bumble bee queens fly low and slow, searching for a nest site. If you find one disappearing into a clump, step back and let her be.

Summer

Early morning is the best time to see grasses flower. On calm days, anthers dangle from the seed heads, and a light tap releases a faint cloud of pollen. This is when the occasional bee may be gathering grass pollen. Look also for skippers perching on grass blades, and for folded or silk-tied leaves that may hold a caterpillar. Leave these shelters closed.

Fall

Seed heads ripen and colors shift. Little bluestem turns coppery, Indian grass turns gold, and switchgrass turns tan to burgundy. This is a good season for prairie birdwatching. Sparrows work through the grasses, often feeding low and staying hidden. Scan with binoculars from the path rather than walking into the planting.

Winter

Standing grasses show their structure under frost and snow. Watch for juncos and tree sparrows feeding on fallen seed, and for tracks leading into dense clumps where small animals shelter. These standing stems are part of the habitat and should be left in place.

How do you keep useful field notes on grasses and pollinators?

A simple field notebook helps you learn which grasses support which visitors on your site. A few consistent details for each observation work better than long descriptions.

• Date, time and weather: include air temperature and wind. Grass pollen releases best on calm, dry mornings.
• Grass species and stage: green-up, flowering with visible anthers, seed ripening or dormant.
• Visitors and behavior: note whether an insect was collecting pollen, resting, laying eggs or just passing through. Record skippers and any leaf shelters you find.
• Birds: which species fed on seed, which used the grass for cover, and roughly how many.
• Habitat details: bare soil patches, signs of nesting, standing stems over winter.

Over a few seasons, these notes show patterns: which clumps the bumble bee queens favor, when the first skippers appear, and which grasses hold birds into winter.

How can you observe respectfully?

Respectful observation means watching without changing what you watch. Stay on mown paths or trail edges, especially in spring when bees are nesting in the ground and birds may be nesting in the grass. Use binoculars or a close-focus lens instead of parting clumps by hand. Do not pick seed heads from public prairies or preserves, and leave folded leaves and tussocks undisturbed. In your own planting, check before cutting or burning in spring, and leave some sections uncut each year as refuge.

Preparing for your next outing

A little preparation makes it easier to notice the grasses. Bring binoculars, a small notebook and a hand lens if you have one. Wear long pants in tall grass and check for ticks afterward. Go out on a calm, sunny morning in mid to late summer. Pick one grass clump and watch it for ten quiet minutes. You may not see a single bee on the grass itself. You will probably see the life around it: a skipper on a blade, a bumble bee checking the base, a sparrow slipping into cover. That is the grass doing its work in the planting.