These beautiful low-maintenance plants bring movement to the garden by blowing in the breeze

Cape rush Chondropetalum elephantinium (Photo by Joshua Siskin)
Cape rush Chondropetalum elephantinium (Photo by Joshua Siskin)

There is one common denominator to the diverse plant groups found on the Monrovia list referenced above. They are all monocots. Flowering plants or angiosperms are divided into dicots and monocots. Dicots have two seed leaves or cotyledons and monocots have one. The two halves of a kidney bean are known as seed leaves, the first “leaves” to show themselves when the seed germinates. A corn kernel, by contrast, or a palm tree seed, when planted, reveals a single slender seed leaf upon germination. You might think that monocots would be a more primitive life form than dicots. After all, isn’t a rose, a notable dicot, a more complex flower than a cornflower, whether a corn’s male tassel or female silk is concerned? And don’t we typically associate complexity with more advanced evolutionary plants and animals? This was the accepted theory regarding which came first – the monocot or the dicot – until the late 19th century.

For more than a century, however, the dominant theory to emerge on this subject maintains that monocots evolved from dicots. Most recently, DNA sequencing has given this theory greater credibility. Also, when it comes to resilience and persistence, qualities that determine fitness and therefore more advanced and sophisticated development in evolutionary terms, monocots outshine dicots. Grasses are found on 20% of the earth’s land mass, much of this in areas where nothing else will grow. Having only one cotyledon, the embryo – which consists of a rudimentary root and first true leaf – of a monocot obtains all its sustenance from a single source whereas a dicot embryo must have two cotyledons fully functioning to sustain its embryonic growth. Monocotyledons such as grasses also grow rapidly and quickly form flowers whereas many dicots must first produce wood and may grow for several years before flowering. Monocots are also tougher than dicots in showing a greater capacity to regrow after being burned or grazed, in addition to being resistant to diseases and insect pests. I must say that, having observed a wide variety of ornamental grasses for decades, I have never noticed any signs of disease or insect damage among them.

Getting back to kinetic plants, I decided to write about them after receiving the following email from Donna Pullman, who gardens in Seal Beach. “I live sort of near the beach and have a spot by the sidewalk to plant in front of a picket fence. I really need to simplify my life with low-maintenance plants. I would love something that can blow in the breeze and have some movement. I like the Mexican feather grass but am thinking it’s maybe not good for our environment. Thank you for any advice.”

I remember the first time I saw Mexican feather grass (Nassella tenuissima) years ago and recognized it as one of the most beautiful plants under the sun. It’s a clumping grass with delicate tresses of green that become blonde and then tawny gold as they mature. What’s more, Mexican feather grass self-sows with alacrity and will soon take over a sidewalk planter, needing only a modicum of moisture to thrive, to say nothing of its swaying back and forth in the gentlest breeze.

The problem with Mexican feather grass, as Ms. Pullman hints, is that it knows no boundaries. Within a few years, it could easily take over your garden and adjacent gardens in your neighborhood as well and eventually spread into the surrounding hills and canyons, choking off native flora. Most nurseries no longer sell this plant because of its invasive tendencies.

Furthermore, when it comes to low-maintenance plants, I would not necessarily place ornamental grasses in this category. Aside from the fact that some of them spread, if not as wildly as Mexican feather grass, even many of the tamer grasses need to be manicured once a year in order not to end up looking ragged. It’s recommended that the popular burgundy fountain grass (Pennisetum setaceum var. Rubrum), for instance, which is sterile and does not self-sow, is best cut back once a year. The pruning procedure may be carried out at any time from late fall to early spring. Trim down so that one-third of each clump remains. If you cut back too far, they may not regrow. Once the clump starts sending up new growth, you can divide it and plant the divisions in other parts of the garden. Make sure you divide when plants are actively growing and before winter comes. Otherwise, your divisions may languish and even die after being transplanted.

Incidentally, there is an ornamental grass that does self-sow but not so aggressively and it is sometimes suggested as a lawn substitute. The species in question is blue oat grass (Helictotrichon sempervirens). There are two types of lawn substitutes, both of which, by definition, are drought tolerant: those that function as lawns, meaning they can accept foot traffic to one degree or another, and those that simply cover the space that a lawn would otherwise occupy. Blue oat grass is of the second type. I once planted it and witnessed it slowly but surely taking over space that once was lawn but had since been turned into perennial beds. I removed most of it but can vouch for its charms. It does not require yearly pruning like fountain grass to keep its fresh countenance and fountainesque shape.

If you do decide to go with grasses, you might contrast burgundy fountain grass with blue oat grass, blue rye grass (Leymus arenarius ‘Glaucus’) or blue moor grass (Sesleria caerulea). Variegated grasses are also popular, with white- and yellow-striped zebra grasses (Miscanthus varieties), and variegated reed grass (Calamagrostis x acutiflora ‘Overdam’)leading the way.

Two pink flowered grasses come to mind and they would also contrast well with the blue and burgundy species mentioned above. One of them is widely considered to have the most beautiful flower tassels of all ornamental grasses. Known as ruby grass (Melinus nerviglumis), it blooms in the hottest summer weather when it displays spellbinding pink inflorescences that turn an attractive burgundy bronze. Photos never do justice to ruby grass, imparting but a small measure of its essential beauty. Pink hair or pink muhly (Muhlenbergia capillaris) is fully capable of surviving a drought, although it looks better when soaked on an occasional basis as it is transformed into a fluffy cloud of pink.

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