The overall effect that Ornamental Grasses give to garden design is texture. This can be spiky, soft and flowing, or just a great vertical accent. Grasses can also offer color, but let's look at the grasses that can offer a spiky look first.
Hakonechloa macra - Japanese Forest Grass
Hakonechloa, pronounced Hack-on-ee-kl-oh-ah, is an easy to grow ornamental grass that performs magnificantly. In winter, the plant disappears, but it is back again in the spring looking even better than when it left.
Hakonechloa macra 'All Gold' makes a nice mound of yellow-gold foliage, contrasting well with dark green plants, but especially well with purple flowers. Another nice planting combination is with variegated foliaged plants, or even with bamboo, as the leaves look similar to the foliage of bamboo.
Plant Japanese Forest Grass in well drained soil that is rich in humus for the best growth. This plant will fail if planted in heavy clay or other sites with heavy, poor draining soil.
Hakonechloa macra - 'Beni Kaze'
Hakonechloa macra 'Beni-kaze' is one of the new "red" cultivars. It forms a flowing mound of red and green foliage that takes on even more striking red tones in the fall. The cultivar name can be translated as "red wind," which describes this plant's autumn look perfectly.
This plant makes a nice accent to other plants with good fall foliage color.
Hakonechloa macra - 'Aureola'
Hakonechloa macra 'Aureola', won the 2009 Perennial of the Year Award. This plant will grow in zones 5 to 9, and prefers a partial shade site, although morning sun is usually ok. Remember, the more sun it gets, the better the color. Also, as seen in this photo, 'Aureola will have some red leaves mixed in with the gold and green, adding interest. This cultivar can take some sun, but too much sun will cause burning and poor growth, so it is very site sensitive. Find that perfect setting and you will be rewarded with plants with amazing colors from early spring to late fall.
Other Spiky Grasses
Bright yellow narrow leaves with green edging makes this evergreen ornamental grass a terrific addition to any garden. Brighten up those dark corners with a plant that look the same all year round. The grass will get wider over time, but no higher, and the spiky form will contrast nicely with other soft, mounded plants, especially the dark colored ones.
Excellent mounding grass with bright light yellow and green striped leaves. The inflorescences are long and showy, and will provide food for hungry birds in winter. Plant as a single specimen or in groups of 3-5 for a lovely effect! The spiky habit adds great contrast to other soft looking plants.
Soft and Flowing Grasses
The grass shown above, Pennisetum orientale, decorates the garden in mid summer with its soft, flowing fuzzy pink bottlebrush like flowers. This lovely plant keeps this display until late fall, and many ask about it during this time. Pennisetum orientale loves lots of sun and well-drained soil. The flowers age to a pale almond color by early fall. Useful accent to go with cut flowers.
Nasella tenuissima 'Mexican Feather Grass'
The Stipa genus has been changed to Nasella, but this species is still tenuissima. Commonly know as the Mexican Feather Grass, the name implies a soft feathery texture that flows in the breeze, giving movement to the garden. We rarely cut this grass back until it becomes matted, then it get's a haircut. The light golden color adds contrast to the darker plants or shadows, drawing the eye. Easy to grow and can be very drought tolerant. It self seeds some, but is easy to pull and rarely gets out of hand.
'Oriental Fountain Grass'
Ornamental grass species like Pennisetum orientale always offer a pleasing, relaxing feeling with their attractive seed heads layering over each other. This grass always seems to look, even in winter when it should be cut back. In milder parts of the country this grass can stay as a decorative element until early spring when it should be cut so new fresh grass will emerge later.
(Syn. Anemanthele lessoniana)
New Zealand Wind Grass
Our favorite grass in the garden! This wonderful orange-green grass will form full 3ft mounds that are a striking color all year. Although not terribly hardy, it will survive cold climates that only go to 15 deg. F. Plant with blue foliage conifers for a great contrast.
Orange colored grass
Stipa arundinacea or 'Pheasant's Tail Grass' has a mixture of orange and green hues and will color an area. One plant will grow 4-5 ft. wide, but only 2-3 ft. high. This grass can require some "combing" to remove the brown dead chaff to keep it looking fresh. It has been reported that shearing to the ground is not recommended for this grass, and "combing" is a better approach in early spring.
Blue colored grass
If you are like me, you are always searching for the color blue to put into the garden. It looks so good against red, orange, or golden colored plants. As it turns out there are a few species of ornamental grasses that display blue colors. This Blue Fescue is easy to grow and long lived, but will require some maintenance to keep the foliage looking bright. Again, the winter "combing" may be required to be happy with the color.
Red Colored Grass
Uncinia uncinata 'Red Hook Grass' is an interesting ornamental grass from New Zealand. It will be spiky and red, to red-brown through the season. In October, just in time for Halloween, the seed head appear and are black. Orange and black are Halloween colors, so this is very appropriate. This grass self seeds some, but is not invasive. We have found that the seedlings are the most red, and if it does seed, you should pot them up to put out in the spring for the brightest red color. Shearing to the ground is not recommended.
Pruning Ornamental Grasses
A genus of ornamental grasses that needs cutting back every year is Miscanthus. Next, I will show you how we do it here in our gardens every year to insure they are fresh and bright. This first photo shows Miscanthus sinensis 'Silberfeil' as it looks in late December. Note that this is the same plant shown at the beginning of this article.
Using hedge shears, cut the grass to within 6-10 inches above ground level. You can also use electric or gas powered shears, or even a chainsaw for faster work. The prunings are quite good to put into a compost pile for aeration.