Perennial grasses are very popular for use in landscapes throughout Colorado for many reasons. Perennial grasses are highly adaptable and able to grow in poor soils similar to what is natively available in our area. They are very easy to maintain and require minimal care, they are well suited to our arid environment, they add winter interest to landscapes that would otherwise look barren, and they come in a large variety of colors, textures, shapes, and sizes. Due to their popularity and abundance in Fort Collins landscaping and throughout Northern Colorado and the Front Range, we are going to discuss what they are, how to care for perennial grasses, different types of perennial grasses, and more!
What Are Perennial Grasses?
First of all, what are perennial grasses? Perennial grasses are also often referred to as ornamental grasses because they often serve a more ornamental purpose, as opposed to more traditional grasses such as Kentucky Bluegrass which are used for lawns and such. Perennial grasses are still extremely practical, helping to reduce erosion, providing shelter for beneficial bugs and wildlife, and more. However, their primary purpose is usually ornamental, adding visual interest, differing textures, vertical height, and more. As can be assumed by the name, perennial grasses are also different types of grasses that are perennial in nature, coming back to life in the spring year after year and not only lasting one season.
Types Of Perennial Grasses
There are countless different types of perennial grasses for zone 5. Here are a few of our favorites. If you are looking for even more options for perennial grasses that grow well in Colorado, check out our Plant Finder!
Feather Reed Grass 'Karl Foerster'
Calamagrostis acutiflora 'Karl Foerster'
Plant Type: Ornamental Grass
Hardiness Zone: 3 - 8
Light Requirements: Partial Sun, Sun
Height: 3" - 6'
Width: 18" - 3'
Foliage Color: Green
Attributes: Drought Tolerant, Easy Care, Winter Interest
Switch Grass Red ‘Shenandoah’
Panicum virgatum ‘Shenandoah’
Plant Type: Ornamental Grass
Hardiness Zone: 4+
Light Requirements: Partial Sun, Sun
Height: 3' - 4'
Width: 3' - 4'
Foliage Color: Green
Attributes: Drought Tolerant, Easy Care, Winter Interest
Flame Grass
Miscanthus sinensis 'Purpurascens'
Plant Type: Ornamental Grass
Hardiness Zone: 4+
Light Requirements: Partial Sun, Sun
Height: 3' - 5'
Width: 24" - 3'
Foliage Color: Green
Attributes: Winter Interest
Zebra Grass
Miscanthus sinensis 'Zebrinus'
Plant Type: Ornamental Grass
Hardiness Zone: 5 - 9
Light Requirements: Partial Sun, Sun
Height: 6' - 8'
Width: 4' - 6'
Foliage Color: Green, Multicolor, Yellow
Attributes: Winter Interest
Muhly 'Undaunted Ruby'
Muhlenbergia reverchonii
Plant Type: Ornamental Grass
Hardiness Zone: 5 - 10
Light Requirements: Sun
Height: 15" - 18"
Width: 18" - 24"
Foliage Color: Green
Attributes: Winter Interest
Blue Oat Grass
Helictotrichon sempervirens
Plant Type: Ornamental Grass
Hardiness Zone: 3 - 8
Light Requirements: Sun
Height: 24" - 30"
Width: 24" - 30"
Foliage Color: Blue
Attributes: Drought Tolerant, Easy Care, Salt Tolerant, Winter Interest
Hardy Pampas Grass
Erianthus ravennae
Plant Type: Ornamental Grass
Hardiness Zone: 5 - 9
Light Requirements: Partial Sun, Sun
Height: 9' - 14'
Width: 4' - 6'
Foliage Color: Green
Attributes: Winter Interest
How To Care for Perennial Grasses
All perennial or ornamental grasses will need slightly different care. In general, ornamental grasses need to be planted in soil that drains well and does not hold onto excess moisture. Soggy or waterlogged soil will cause problems for your perennial grasses and can sometimes lead to them dying. So, be sure to plant your perennial grasses in well-draining soil and amend soil appropriately before planting if the soil in the area is not conducive. Heavy clay soils that are so common here in Colorado should be amended. You will also want to be sure not to water your perennial grasses too frequently, as the same issues could arise with overwatered plants. Many types of perennial grasses require full sun, and some can tolerate partial shade, though perennial grasses rarely grow well in fully shaded areas.
When Should You Plant Perennial Grasses?
Ornamental grasses are best planted in the spring. Planting in the spring allows for the plant to begin to establish a robust root system before the heat of the summer sets in. Spring planting also ensures that your new perennial grasses will have the most time possible to grow deep roots which will increase the plant's odds of surviving its first winter season. Perennial grasses can be planted in the fall, however, this gives them less time to establish their roots. To learn more about best practices when planting trees, shrubs, or perennial plants, check out our Planting Guide!
When Do You Cut Back Perennial Grasses?
Perennial grasses are fantastic for providing winter interest. Even though they are not actively growing throughout the winter season, the height and texture of perennial grasses add a lot to any landscape. For this reason, it is best to wait to cut back your perennial grasses until spring. This also helps to insulate the plant throughout the winter and provides shelter for critters throughout the cold months. If you are wondering when to cut back perennial grasses, wait until spring and then cut them back just before new growth begins to emerge.
Perennial Grasses for Colorado
If you have any questions about how to grow perennial grasses, when to cut back perennial grasses, or the different types of ornamental grasses for Colorado, let us know! Our landscape designers will work with you to select the best perennial grasses for your space. Use our online Plant Finder to start getting some ideas of your own or reach out to us to get started on your landscape plan today!