Growing Northern Sea Oats as a Cut Flower
Northern Sea Oats (Chasmanthium latifolium) is a perennial grass with beautiful seedheads useful in both fresh and dried floral arrangements. This lovely ornamental grass is also native to the eastern United States, and makes a great plant for naturalizing landscapes. Northern Sea Oats are fairly compact with a mounding habit, producing a bounty of stems for cutting in early autumn. Cut flower stem length ranges from 24-36” making Sea Oats a wonderful accent for floral arrangements. Hardy in USDA Zones 5-9, they can be divided every few years to remain vigorous.
Here’s how to divide your ornamental grass plants quickly and easily.
How to Divide Northern Sea Oats
First, locate the clump you want to divide. If dividing in the spring, you can use last year’s brown stems as a “handle” when handling so you don’t damage new emerging growth.
Next, carefully dig around the clump, preserving as much of the roots as possible. As you loosen it, begin lifting the clump away from the ground.
Once lifted, gently shake away any loose soil.
Now, using a sharp tool like pruners or snips, split the clump into 2 or 3 new sections. You can gently pull apart the clump to create the divisions.
Once you have all your divisions separated, you’re ready to plant!
How to Grow Northern Sea Oats Divisions
Northern Sea Oats are easily started from seed and grow best in well-drained to moist soils that receive full to part sun. Space plants 12” apart for cut flower production, and up to 18” if planting for the landscape.
Bury the new divisions so the roots are completely underground. Green shoots and top growth should be left exposed. Water well to settle the soil around the roots.
When to Divide Northern Sea Oats
This ornamental grass can be divided in either spring or fall, every 2 to 3 years.
Harvesting for Cut Flowers
Sea Oats are ready for harvest when all the seed heads on a stem have opened and the color begins to darken, with some green still remaining. Use them fresh in floral arrangements, or dry for later use.
Northern Sea Oats are my favorite perennial ornamental grass to grow, and I hope you’ll find its arcing stems of copper-colored airy seedheads useful and beautiful too!