Easy Native Grass for Shade and Sun: Northern Sea Oats

Excellent for dry shade, winter interest, cut flowers and more.

Northern sea oats (Chasmanthium latiflolium) is an extremely adaptable native grass. Sun to shade and dry to wet soils, it does it all. While it can grow up to 5' tall, in dry shade it seems to keep to about 3' in height. There are lots of plusses to this native grass but before we get to those, please do know in certain situations, northern sea oats can spread by rhizome and seed and really take hold. As with many plants, this is most likely to happen when planted in its ideal growing conditions. For northern sea oats, ideal conditions are moist to wet soils and dappled shade. Depending on your situation, this may be good or bad! To avoid aggressive spreading, plant northern sea oats in sunny dry areas or in dry shade.

Tough to Grow Spots

Northern Sea Oats Massed Beneath Mature Oak Tree

mature trees

Northern sea oats can be planted in deep shade beneath the canopies of large mature trees. Here, it is planted en masse. If you are planting beneath a large tree, it is advisable to plant 2" plugs rather than larger plant sizes to minimize disturbance to existing root systems of trees. Plugs of northern sea oats can be ordered through Izel Plants.

slopes

Northern Sea Oats in Early Spring as Part of Mixed Planting by Native Roots Conservation Landscaping

Northern sea oats can be used on slopes and for erosion control. The root systems are generally reported to be about 10" deep. These roots are not particularly deep for a native grass but deep enough to do the job.

Garden Interest

Northern Sea Oats in Fall

Northern sea oats are modest in scale and not overwhelming, even in smaller gardens. Graceful arching stems with interesting seed heads add significant texture. The stems catch even the lightest of breezes and add movement in your garden.

This is also a four season plant. In smaller gardens, a good design strategy is to feature plants with multiple seasons of interest and this fits the bill. Fall colors are a bronzy tan. Backlit by sun, the grass glows. Northern sea oats may remain standing most of the winter, particularly in more sheltered locations. This adds color, texture and movement in winter months. In spring, new growth emerges and by June new seed heads usually appear.

Newly Planted Northern Sea Oats at Wildflower Native Plant Nursery

You can plant northern sea oats en masse, in drifts among other perennials or scattered throughout an area in a sort of matrix planting style. Again, stick to dry sunny areas or dry shade to avoid a situation where the grass really takes off.

For those of you who contend with deer, the North Carolina Extension service describes northern sea oats as "highly resistant to deer." Northern sea oats are great additions to live or dried flower arrangements as well. More plusses!

Ecological Benefits

Northern sea oats add wildlife benefits to our gardens too. This grass provides shelter, hiding places and food for birds and small mammals. Northern sea oats are a larval host for several butterflies including a couple of skippers. If a plant is a larval host it means the plant is food for the caterpillars of those butterflies and where there are caterpillars there are birds - always a good thing.

If you grow northern sea oats in your garden, please do share your experience!

Happy Gardening.