Why pair grasses with flowering shrubs
Flowering shrubs have big, rounded shapes and bold leaves. Grasses are narrow, airy and in motion. Together they give a bed contrast in texture and form, and grasses fill the quiet periods when a shrub is not in bloom. Grasses also add height variation in front of or behind a shrub.
Match conditions first
Pairings work when plants share similar needs, and that is often the main challenge with hydrangeas.
- Hydrangeas generally appreciate consistent moisture, with many types preferring morning sun and afternoon shade, though sun tolerance varies by species.
- Many ornamental grasses are drought tolerant and prefer full sun and well-drained soil.
Because of that mismatch, choose grasses that tolerate moderate moisture and some shade, or give the combination a position where both are satisfied, such as morning sun with afternoon shade.
Grass picks for hydrangeas
- Hakone grass: cascading and shade-tolerant, with a flowing habit that softens hydrangea bases. See shade-tolerant grasses.
- Sedges (Carex): evergreen, low and tidy for the foreground (see the best carex varieties for shade). Chartreuse forms stand out against dark green hydrangea leaves.
- Mondo grass: a dense, dark edging. Compare it with liriope in liriope vs mondo grass.
- Feather reed grass ‘Overdam’: described as happy in sun or part shade, and good behind lower shrubs.
- Northern sea oats: tolerates shade, though it can self-seed widely.
For sunnier hydrangea locations such as panicle hydrangeas (which tolerate more sun), dwarf fountain grass ‘Hameln’ or compact Miscanthus can work. See small ornamental grasses.
Other flowering shrubs
- Spirea: mounded shrubs that bloom in white, pink or red, and often develop fall color. Fountain grass or blue fescue works at its feet.
- Butterfly bush: fine, sun-loving partners such as switchgrass or feather reed grass. Butterfly bush is considered invasive in some regions, so check locally.
- Roses: low grasses and sedges soften bare lower stems.
- Viburnum and weigela: taller grasses in the background, plus shorter ones in front.
- Rhododendron and azalea: sedges and mondo grass in acidic, part-shade conditions.
- Ninebark and smoke bush: dark foliage beside golden or blue grasses.
Layout
- Place shrubs first, spaced for their mature width.
- Add grasses in front or between, in odd-numbered groups. See landscaping with ornamental grasses.
- Keep taller grasses behind or to the side of shorter shrubs so they do not hide the flowers.
- Repeat the same grass along the bed to tie it together.
- Consider bloom and color timing so something is interesting from spring to fall. For other shrub ideas, see what shrubs look good together.
Watch the water
If you use drought-tolerant grasses next to thirsty hydrangeas, group plants with similar needs together or water the shrubs at their bases. Mulch helps retain moisture, and perennials such as coneflower and sedum may suit the drier side of a bed. See perennials to plant with ornamental grasses. To better understand the two plant types, see the difference between shrubs and grasses.