What counts as an ornamental grass
Ornamental grasses are grasses (and a few grass-like plants) grown for their foliage, flower plumes and seed heads rather than for a lawn. Gardeners also call them decorative grasses. They add movement, texture and height, and many hold their shape through autumn and winter.
Search results for “types of garden grasses” often mix in lawn turfgrasses such as Kentucky bluegrass or Bermudagrass. Those are grown to be mown and walked on. This guide covers the plants you put in beds, borders and containers.
Four ways to sort garden grasses
No single list covers every grass, so it helps to sort by the things that affect where a plant will work:
- Season of growth: cool-season or warm-season.
- Growth habit: a tidy clump or a plant that spreads.
- Size: from 6-inch edgers to grasses taller than a person.
- Light and moisture: sun-lovers, shade-tolerant types and moisture-lovers.
Foliage color (blue, golden, variegated, bronze) and whether the plant stays green all winter are also useful filters.
Cool-season vs warm-season grasses
Cool-season grasses do most of their growing in spring and fall and are often among the first to green up. Warm-season grasses wait for warmer weather, then grow and flower in summer heat, and usually turn tan or brown in winter. The difference decides when you plant, divide and cut back. Our guide to warm-season vs cool-season ornamental grasses has plant lists for each.
Typical examples:
- Cool-season: feather reed grass (Calamagrostis), blue fescue (Festuca glauca), blue oat grass (Helictotrichon sempervirens), tufted hair grass (Deschampsia).
- Warm-season: maiden grass (Miscanthus), fountain grass (Pennisetum), switchgrass (Panicum), little bluestem (Schizachyrium), pink muhly grass (Muhlenbergia capillaris), prairie dropseed (Sporobolus heterolepis).
Some plants do not sort tidily. A few warm-season grasses start growing early in spring, so check a specific plant’s habit before assuming.
Clumping vs spreading grasses
Most garden grasses are clumpers: they form a tuft that slowly widens over the years. Others spread by underground rhizomes or surface runners and can form large patches. A third group behaves as a clumper but drops a lot of seed.
If you want a plant that stays where you put it, look for clump-formers that are not heavy self-seeders. Our list of non-invasive ornamental grasses covers this in detail. Because invasiveness varies by region, check your local extension service or state invasive plant list before buying. Pampas grass is a good example of a plant that behaves very differently from one region to the next, as explained in our article on whether pampas grass is invasive.
Tall, medium and short grasses
Tall (roughly 5 feet and up): Many Miscanthus cultivars reach 5 to 8 feet, and some reach more. Switchgrass, big bluestem and Indian grass also reach 5 feet or more in some forms. These suit the back of a border, a screen or a focal point. Giant reed (Arundo donax) can reach well over 10 feet but is invasive in some areas, so it is not a plant to choose casually.
Medium (about 2 to 5 feet): ‘Karl Foerster’ feather reed grass, fountain grass, little bluestem, pink muhly grass and prairie dropseed fall here. They work in the middle of beds and in drifts.
Short (under about 2 feet): Blue fescue, Japanese forest grass, many sedges and dwarf fountain grasses suit edging, rock gardens and containers. Our guide to blue ornamental grasses covers the silver-blue options.
Heights vary by cultivar, so use the plant tag as the final word.
Grasses for shade
Most true grasses want sun, but a few tolerate part shade or dappled light. Our guide to ornamental grasses for shade covers them in detail:
- Japanese forest grass (Hakonechloa macra), with arching golden or variegated blades.
- Northern sea oats (Chasmanthium latifolium), with flat dangling seed heads.
- Autumn moor grass (Sesleria autumnalis) and tufted hair grass (Deschampsia cespitosa).
- Sedges (Carex) and woodrushes (Luzula), which are grass-like rather than true grasses. See grasses vs sedges for the difference.
Year-round and evergreen options
Many ornamental grasses go dormant in winter, but some stay green, and the dormant ones can still look good with tan foliage and seed heads standing. If winter appearance matters to you, read year-round ornamental grasses for four-season interest and the companion article on evergreen ornamental grasses that stay green all year.
Fountain grass vs muhly grass
Both are warm-season clumpers with showy plumes, and gardeners often mix them up.
- Fountain grass (Pennisetum): Arching, mounding foliage topped by bottlebrush-style plumes in cream, pink, burgundy or near-black. Sizes range from compact dwarfs to taller types, depending on the species and cultivar. Some tender types, such as purple fountain grass, are treated as annuals in cold climates.
- Muhly grass (Muhlenbergia): Fine, narrow blades and airy clouds of pink or white flowers in late summer and fall. Pink muhly grass is commonly about 3 feet tall and is valued for drought tolerance. See how to grow pink muhly grass.
If you want a bold, bottlebrush look, choose fountain grass. If you want a soft haze of color in fall, muhly grass is the usual pick. For the bigger comparison between Pennisetum and Miscanthus, see Miscanthus vs Pennisetum.
Types of feather reed grass
Feather reed grass (Calamagrostis) is a cool-season group with upright, narrow plumes. The ones gardeners meet most often are:
- ‘Karl Foerster’ (Calamagrostis × acutiflora): the classic, with very upright stems and early-summer plumes that fade to tan.
- ‘Overdam’: a variegated form with white-striped leaves.
- ‘Avalanche’: another variegated selection.
- Korean feather reed grass (Calamagrostis brachytricha): arching foliage and plumes that appear later in the season, often tolerating more shade than ‘Karl Foerster’.
Grasses for cold climates
If you garden in USDA zone 4 or colder, check the hardiness rating on each plant. Grasses that are commonly rated for zone 4 or lower include blue fescue (zones 4 to 8), little bluestem, prairie dropseed, switchgrass, Indian grass and blue grama. ‘Karl Foerster’ is often sold as hardy in zone 4 or 5, depending on the supplier. Ratings differ between growers, so treat them as a guide and consider your microclimate. Our list of cold-hardy grasses for zones 3 and 4 goes further.
Grass-like plants: sedges, rushes and others
Sedges, rushes and plants such as mondo grass or sweet flag are often sold alongside ornamental grasses. They are not all true grasses, but they fill the same design roles, and many stay green through winter. They are worth knowing about if you want shade or moisture tolerance.
Choosing and caring for your grasses
Start with the site (sun, soil drainage, space), then pick a height and season of interest. Once planted, most grasses need little work: some water in the first year, little or no fertilizer, a yearly cut-back and occasional division. Our guide on how to care for ornamental grasses covers the routine, and whether to cut back all ornamental grasses in spring explains timing.