Plant Type
Sunlight Amount


Blue Oat Grass

Blue oat grass boasts one of nature’s most elusive plant colors along with panicles of brownish spikelets in fall that reach far above the foliage. Add this elegant, ornamental specimen to a cottage garden to offer a cool contrast to warm green foliage and bright blossoms. Plant it in a rock garden and enjoy the soft blue hue among the browns and grays. Nestle it in a contemporary garden to gain its standout color and texture. Plus, this tough ornamental grass is easy to grow and resistant to deer, drought, and even air pollution.

genus name
  • Helictotrichon sempervirens
  • Sun
plant type
  • 1 to 3 feet
  • From 2 to 2 1/2 feet
foliage color
season features
problem solvers
special features
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9

Best Planting Partners

Plant blue oat grass alongside other blue-tinged plants for an intriguing garden display. Dwarf blue spruce and juniper offer evergreen blue foliage that complements bristling clumps of blue oat grass. Pink-flowering perennials, such as butterfly bush (Gaura), Japanese anemone, and turtlehead (Chelone obliqua), make pretty pastel partners for the spiky mounds of blue-gray leaves. Forgo planting companions, if you like, in favor of a mass of blue oat grass that creates a tufted, easy-care groundcover.

Blue Oat Grass Care Must-Knows

Plant blue oat grass in full sun and well-drained, average-to-dry soil such as that found in rock gardens and curbside planting beds. (Crown rot is a risk if this grass is grown in poorly drained soil.) Water newly planted clumps of blue oat grass every week or so for the first growing season to encourage a strong root system. Supplemental watering is rarely necessary after the first year.

Remove old foliage at the beginning of every growing season before new foliage emerges. Cut the foliage back to about 3 inches above ground level. During late winter (between early February and the end of March) is a great time to snip away old foliage. Use a manual or powered hedge trimmer for quick and easy stem removal.

Blue oat grass can be divided every three or four years in spring. Dig up the entire clump, then use a sharp spade to slice it into three or four pieces. Replant the divisions and water them regularly to encourage strong root growth.

Plant Blue Oat Grass With:

Sedums are nearly the perfect plants. They look good from the moment they emerge from the soil in spring and continue to look fresh and fabulous all growing season long. Many are attractive even in winter when their foliage dies and is left standing. They're also drought-tolerant and need very little if any care. They're favorites of butterflies and useful bees. The tall types are outstanding for cutting and drying. Does it get better than that? Only in the fact that there are many different types of this wonderful plant, from tall types that will top 2 feet to low-growing groundcovers that form mats. All thrive in full sun with good drainage. Ground cover types do a good job of suppressing weeds, but seldom tolerate foot traffic. Some of the smaller ones are best grown in pots or treated as houseplants.

Asters get their name from the Latin word for "star," and their flowers are indeed the superstars of the fall garden. Some types of this native plant can reach up to 6 feet with flowers in white and pinks but also, perhaps most strikingly, in rich purples and showy lavenders.Not all asters are fall bloomers. Extend the season by growing some of the summer bloomers, as well. Some are naturally compact; tall types that grow more than 2 feet tall benefit from staking or an early-season pinching or cutting back by about one-third in July or so to keep the plant more compact.

Nothing beats a dahlia for summer color. Growing these varied, spiky flowers is like having a box of garden crayons at your disposal. The flowers form on branching, fleshy stems or open in solitary splendor on the bedding-plant types in mid- to late summer. Several different flower categories, from the petite mignonettes to the gigantic dinner-plate dahlias, offer possibilities for any space.Expert dahlia growers recommend pinching off the first crop of side flower buds to encourage vigorous plant branching and larger flowers in peak season. All dahlias are fodder for brilliant seasonal cut bouquets and are always one of the most popular cut flowers at local farmer's markets. Their blooming season extends into fall and is only halted by the first frost.Gardeners in climates colder than Zone 8 should cut back the withered foliage after the first frost and dig up tubers to store over winter. For a fast start with dahlia plants before it's safe to plant outdoors, pot the tubers up, water sparingly and grow in a sunny location until sprouts appear, and then transplant outdoors after the last frost.

It's time to debunk a garden myth: Goldenrod does not aggravate allergies! The pollen is too heavy to fly in the wind and instead sticks to the legs of the insects and butterflies that feed on its nectar.It's one of the most glorious flowers of late summer and early autumn, with the wild type blanketing ditches and other open, moist sunny places. In your own garden, choose the hybridized types that are shorter, longer-blooming, and don't spread out of control. Divide or take cuttings of these to increase your supply; seed will not come true.