Aside from adding texture, height, form and color to any garden, ornamental grasses can withstand the elements, as well as provide gratification in a short amount of time. Ornamental grasses can be invasive, but putting them in containers is one way to prevent spreading to other plants. Cold and warm season ornamental grasses are the two main types of ornamental grasses. Choose the type that will do well in your container garden.
Blue fescue is a mound-forming type of perennial ornamental grass that can grow from 6 to 18 inches high. Using blue fescue as accent in a big container garden can provide a backdrop to smaller plants. Its blue-gray foliage is an attractive addition to a container garden, whether accompanied by other plants or on its own.
The two types of blue fescues that you can consider for a container garden are Large Blue Fescue (Festuca amethystina) and Blue Fescue (Festuca ovinia var. glauca). Both varieties can grow in zones 5 to 9; however, Large Blue Fescue is hardier and will adapt well in zone 4. Planting in well-drained soil is ideal in growing both fescues. Watering regularly and dividing blue fescues frequently will maintain vigorous growth.
Blue Oat Grass
Blue oat grass (Helictotrichon sempervirens) is more enduring than blue fescues. It is one of the best choices in accenting a container garden. The metallic-blue foliage shimmers, especially during sunny days. Blue oat grass has a mature height of 12 to 18 inches and can spread from 20 to 24 inches wide. It does well in zones 4 to 11, well-drained soil and moderate to dry moisture.
Mainly planted for its metallic-blue foliage, blue oat grass also produces flowers with golden wheat color resembling one-sided oat panicles. The flowers appear in June and can grow from 1 to 2 feet higher than the leaves. Planting blue oat grass and canna lilies with burgundy leaves together can provide a dramatic effect because of their contrasting colors.
Golden Variegated Hakone Grass
Golden variegated Hakone grass (Hakonechloa macra 'Aureola'), is a mound-forming, non-invasive rhizome grass. Its brilliant yellow, bamboo-like foliage has streaks of green, which can turn into an intense ruby pink during the fall.
Ideal for zones 4 to 11, golden variegated Hakone grass has a mature height of 12 inches and can spread slowly from 14 to 18 inches wide. It prefers moist, well-drained, fertile soil under shade or partial sun. The foliage will turn into reddish-brown when exposed under too much sunlight. Planting three or more mounds of golden variegated Hakone grass or combining with other shade-loving plants can add mass to a container garden.