I recently purchased some ornamental grass from Bill Holt, owner of Willowmist grasses and asked if he would be kind enough to do an interview by email. He agreed and what follows are my questions and his answers. Thanks Bill!
Q. How long have you been growing ornamental grasses?
A. We brought our first grasses in the spring of 1999.
Q. What got you interested in growing them?
A. We were looking for something unique, and Teresa saw a TV program about Kurt Bluemel’s grasses nursery in Maryland. He studied under some of the iconic European grasses pioneers, and brought the concept of ornamental grasses here to the US.
In addition to their uniquely casual beauty and elegance, the grasses appealed to us because they require virtually no chemicals or fertilizers, which meant that we could grow them here without any worries about impacting the abundant wildlife: deer, turkeys, fox, coyote, weasels, Great Blue Heron, mallards, bats, various hawks, osprey, muskrat, pheasant, and more.
Q. When is the best time to to divide grasses?
A. Most grasses can be divided well into late August, but the sooner the better. A divided grass needs to regrow root mass to survive the coming winter (i.e. “reestablish” itself), and the sooner that process begins, the better. The more weeks the grass has to regenerate root mass before winter, the better. Some varieties are pretty tolerant fairly late into fall, such as Miscanthus ‘Purpurascens’ (Flame Grass) and most of the Switch Grasses, but generally speaking, sooner is better.
Q. What is the biggest mistake or misconception people have when it comes to growing ornamental grass?
A. In the early days of the ornamental grasses industry here, many grasses proved to be aggressive spreaders, and soured many people on the idea of grasses in general. That is very unfortunate, and was simply the result of ignorance in choosing varieties. The most spectacular ornamental grasses are very well-behaved clump-forming varieties, which rarely (if ever) self-sow, and are very easy to control.
Q. Can ornamental grass be grown over a septic tank or leech field?
A. Our ornamental grasses generally only put down about a 15″ root ball, so they can be used safely over a septic tank, and in most cases over a leach field.
Q. Which grass is your personal favorite?
A. My personal favorite grass is Miscanthus sinensis ‘Malepartus.’ It is a cultivar (“cultivated variety”) developed by Ernst Pagels, one of the industry pioneers, and is superior in every respect for New England gardens. It blooms earlier than any of the other Miscanthus, is most reliably upright, has a very elegant form, and bears the most spectacular variety of fall colors. Every color of the grasses fall rainbow is visible in Malepartus – including deep blood red stems.
Q. Do you have one tip that you can share that most people may not be aware of?
A. My best tip for grasses is a technique I developed called “coring” for keeping plants vigorous or restoring them in the center as they age.
Like many perennials, grasses typically develop a “doughnut” effect as they age. The center loses vigor, and can die out to the point of rot. You end up with a ring of new green foliage around the perimeter, but nothing in the center.
Most texts advise digging out such plants, dividing them, and putting back some piece of the original to start over.
This is a lot of work, and costs you at least 3/4 of the plant you’ve been nursing along for 3-4 years.
Instead, use a Sawzall or axe to cut up the center of the plant, removing the dying portion, all the way to the bottom of the root ball.
Backfill the hole with good soil and water like a new plant. The younger growth at the outer edges will regenerate into the middle, and be very vigorous.
Better yet, don’t wait for the center to start dying. Every spring when you do your cut-back, make stimulating cuts through that center. It’s GRASS. Cutting just makes it grow faster. If you stimulate the center every spring, you’ll probably avoid the doughnut effect entirely, and never need to resort to a full coring.
Visit Bill’s website, Willowmist, for more great information on ornamental grass.