How To: Divide Ornamental Grasses

Ornamental grasses continue their popularity in both residential and commercial landscapes. Their graceful habit, variety of texture and color and low maintenance keep them on our landscape palette. However, they do need some attention periodically. Depending on the species, ornamental grasses may potentially become overgrown for the location you have selected or may flop over as they get larger. Some grasses also die out in the center — a natural growth pattern — and need for you to divide them, restoring their tidy appearance. When that time comes, here's how to approach the job.

  1. Most ornamental grasses can be divided in the spring. There are some exceptions, and many can be divided in either spring or fall, so be sure to check individual species. Miscanthus, Andropogon (big bluestem), Arundo, Chasmanthium (Northern sea oats), Panicum, Pennisetum, Cortaderia and Erianthus are a few of the grasses that you can safely divide in the spring.

  2. Long pants, long sleeves and thick gloves will help protect you from cuts. Some ornamental grasses have minute teeth along the leaf margin (and some teeth are not minute) that inflict phantom cuts. You may not feel them immediately, but the results are sure to irritate.

  3. If the grasses weren't cut back last fall, they will be easier to divide if you first remove last year's foliage. Tying large clumps with a bungee cord and covering over the top with a garbage bag before you cut it back will help contain the debris.

  4. You'll need some sharp tools. Again, for emphasis: Sharp tools are needed. Clumping grasses form dense mats of crown, stem and roots that are tough to cut through. An axe, saw, shovel and a strong back are needed.

  5. Dig the rootball with some soil still attached. Some grasses tolerate being divided bare-root, but some are sensitive and may not transplant well.

  6. For those grasses that naturally die out in the middle, take your divisions from the edge where vigorous growth occurs. Depending on the size of the clump, you may end up with 4 or 8 divisions. The larger the division, the sooner it will grow to size. Discard the dead center.

  7. Keep the divisions out of the sun until ready to transplant. Transplant as soon as possible after dividing. Be sure to set the crown at the same depth it was previously growing.

Want to use this article? Click here for options!
© 2020 Penton Media Inc.

Interactive Products

Equipment Blue Book

Used Equipment Valuation Guide

Riding mowers, lawn tractors, snow throwers, golf carts


Grounds Maintenance Jobs

search our jobs database, upload your resume