Gardening 101: Bowles’ Golden Grass

Bowles’ Golden Grass, Milium effusum ‘Aureum’

Although I routinely hear clients say chartreuse is a color they don’t want in their garden (for reasons they can’t usually explain), I maintain my love for this hue, especially in the shade.

Bowles’ golden grass (Milium effusum ‘Aureum’) is a cultivar of wood millet grass that is a stellar example. It proves my point that a sun-compromised corner of the garden usually needs a little brightening, which can be successfully achieved with brilliantly colored foliage in a limey chartreuse shade. If your garden has a shaded spot that needs illuminating (and you are not a chartreuse hater), please keep reading to learn more about this charming perennial grass.

Edward Augustus Bowles (Gussie to his friends) was a revered British horticulturist, plantsman, and garden writer who had a talent for spotting noteworthy plants.  M. effusum ‘Aureum’ is one of more than 40 varieties named for him and during the lifetime of Vita Sackville-West was introduced to the gardens at Sissinghurst Castle.

In cultivation, this colorful selection with its golden appearance brings an incandescent light to shady spots and, as it changes through the seasons, makes a year-round contribution to the garden.

M. effusum ‘Aureum’ is a yellow cultivar of wood millet grass (which is more commonly found in plain green form). The cool-season tufted grass is native to eastern North America and Eurasia, and can be found thriving in woodland areas. It can thrive in partial shade in moist conditions in USDA growing zones 5 to 9.

A semi-evergreen grass, Bowles’ golden grass gets going in early spring when bright yellow leaves erupt vertically, then form a loose clump that grows up to 2 feet high and wide. As summer progresses, the grass begins to arch and weep; the color gradually turns a vivid lime-green.

Milium flourishes where summers are cool or mild; in hotter regions, the grass will go partially dormant in summer.  And while this is a short-lived perennial grass, it will come true from seed and self-sow readily if allowed, which of course I recommend.

Cheat Sheet

• Plant clumps of Bowles’ golden grass in groups of threes or fives as part of a woodland design or at the edge of a shady cottage border.
• A natural-born mingler, wood millet grass associates successfully with spring bulbs and other shade-loving perennials. Yellow and blue are always a good combination, so try combining with blue Campanula muralis or blue grape hyacinth.
• Luckily Bowles’ golden grass is pest- and disease-free, and avoided by deer.

Keep It Alive

• As with most golden-leaved plants, this grass prefers partial to full shade to prevent the thin leaf surface from burning. Full sun can be attempted if the ground is kept constantly moist.
• Regular to ample water is a must.
• When planting, incorporate compost into the soil to help retain moisture as M. effusum ‘Aureum’ requires moist, humus-rich, well-draining soil.
• You can tidy up tired leaves and old stems by cutting back the grass to the ground (but avoid doing this while the plant is bearing seeds, unless you don’t want it to self sow).
• Collect seeds by running your finger and thumb upwards on the flower stem. Broadcast immediately or sow seeds in a seed tray in loamy potting soil.

Read more growing tips at Bowles’ Golden Grass: A Field Guide to Planting, Care & Design in the curated Grasses 101 collection of our Garden Design 101 section. For more ideas to incorporate perennial grasses into a landscape, read:

• Gardening 101: Basket Grass
• Leaves of Grass: 9 Ways to Create Curb Appeal with Perennial Grasses
• Hakone Grass: A Field Guide to Planting, Care & Design
• 10 Garden Ideas to Steal from Superstar Dutch Designer Piet Oudolf
• Gardening 101: How to Care for Perennial Grasses