Milium

( MIL - ee - um )

At-A-Glance Information

This genus includes species commonly called Wood Millet, American Milletgrass, or Golden Grass. They are perennial, cool-season tuft grasses that require light shade and regular to ample water to perform well in the landscape and are native to eastern North America and Eurasia. The species most widely grown as a garden ornamental is Milium effusum. Cultivar 'Aureum' forms a clump 2 feet tall and just as wide, with bright green-gold foliage that takes an arching, weeping form as it ages. Grow America Milletgrass in USDA hardiness zones 4-9 or Sunset growing zones 3b-9 and 14-17 (to find your zone, click here: Zone Map).

Caring for Milium

Milium grasses should be planted in a space that receives full sun; between 6 and 8 hours is ideal. Ensure that soil is well-draining, moderately fertile, and has a pH of between 5.5 and 7.5 (slightly acidic to neutral). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, these grasses need regular water to stay healthy. As a general rule of thumb, water these grasses deeply once a week during the active growing season (spring through fall).

Prune these grasses at any time during their active growing season to clean up their appearance, removing dead, damaged or diseased foliage. In early springtime each year, cut the plant down to about 2-4 inches above the ground to encourage a new flush of growth. Milium plants will form tufts or clumps over time that should be divided every few years to ensure plant health. For instructions on how to successfully divide Milium plants, see the Propagation section below. The average life span of these short-lived perennial grasses is between 3 and 5 years. They will readily self-seed in the landscape, providing new plants for the garden indefinitely.

Caring for Milium in Containers
Container cultivation is a great way to enjoy the beauty of these plants while curbing their aggressively spreading roots. Choose a container that is at least 12-14 inches wide. Ensure that the pot has adequate drainage holes on the bottom to allow for excess water to flow away. Fill with a well-draining potting mix amended with organic material and perlite, and top with a layer of mulch to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water regularly as the plant establishes itself in its new home. Once established, waterings can be lessened. Milium plants grown in containers will need more frequent irrigation than those grown in the ground. As a general rule of thumb, water whenever the top few inches of soil feels dry to the touch. Prune to remove dead, damaged, or diseased foliage at any time during the growing season. Every few years, check the bottom of the pot to ensure that the plant is not outgrowing its root space. If roots are growing through the drainage holes in the bottom of the container, it is a good indication that it needs to be potted up; choose a slightly larger container and repot.

Propagation

Milium grasses are best propagated via division. These plants will also re-seed freely in the landscape, providing seedlings that can be dug up and transplanted elsewhere. To propagate your Milletgrass, follow the instructions below:

Propagating Milium by Division
To propagate via division, you will need a clean shovel, clean pruning saw (optional), extra pots if you are not going to immediately plant your divisions in the ground, and well-draining soil to fill the pots. To propagate your Milletgrass by division, follow the instructions below:

In early fall or early springtime, identify the area of plants you're going to divide. Start by loosening the soil around the plant with your shovel, working your way inward to avoid causing damage to the bulbs. Once you've gotten your clump out of the ground, run water over it or simply shake it to remove excess dirt. Then, lay it out on its side.
Separate the clump into multiple pieces, each with a healthy root system and adequate above-ground growth.
Prepare the planting area, whether it is a container or bed in the garden, and then plant the divisions. Afterwards, resume regular care.