Plant problems

Why Are My Melica Leaves Curling?

Q: Why are my melica leaves curling?

Melica (melic grass) leaves curl and brown most commonly in UK gardens because of drought stress in a hot, dry, sunny position (the main ornamental melica species grown in UK gardens — Melica altissima and Melica transsilvanica — are plants of partially shaded, moist to moderately dry woodland edges and hedgerow habitats; they prefer partial shade to dappled light and moderately moist, reasonably fertile soil; in full sun in dry, light soil in a hot UK summer, the broad, flat leaves curl along their length and brown at the tips as heat and moisture stress combine, particularly in newly planted or container-grown specimens), summer dormancy in hot, dry conditions (many melica species, particularly the smaller-growing ones like Melica uniflora, go through a period of semi-dormancy in the hottest part of a UK summer — particularly in a dry year — where the foliage browns and the plant appears to be dying; this is the normal summer rest period for these woodland grasses, which are cool-season plants that grow most actively in spring and autumn rather than in the heat of midsummer; the plants regenerate fully in late summer and autumn), or deep shade without adequate moisture (melica species prefer partial shade but do need some light to grow well and flower; in very deep, dry shade they produce limited thin leaves that curl and yellow rather than the broad, glossy leaves of a well-grown specimen). Melica (melic grass) is a genus of approximately 70 to 80 species of mostly cool-season, clump-forming grasses distributed across temperate regions of Europe, Asia, and the Americas; the species most commonly grown in UK gardens are Melica altissima (Siberian melic, to 80 to 100 cm), Melica transsilvanica (Transylvanian melic, to 60 to 80 cm), and Melica uniflora (wood melic, a native UK species), grown primarily for their attractive, often one-sided or nodding flower spikelets in late spring to early summer.

Q: Is melica a good shade grass for UK gardens?

Yes, melica species are among the most useful ornamental grasses for partially shaded positions in UK gardens; they thrive in the kind of dappled or partial shade that excludes many sun-loving ornamental grasses, making them valuable for woodland gardens, north-facing borders, shaded areas under trees with reasonable soil moisture, and shaded courtyard gardens where most ornamental grasses would struggle. The most ornamentally significant species for UK garden use are Melica altissima (Siberian melic), which forms upright, arching clumps to 80 to 100 cm with attractive, one-sided, purple-tinged or white flower spikelets from May to July, and Melica transsilvanica (Transylvanian melic), which is similar in habit and slightly more compact; both are reliable in partial shade in moderately fertile, moist to moderately dry soil. Melica uniflora (wood melic) is a native UK grass of semi-shaded woodland and hedgerow habitats; it is more delicate and smaller-growing (to 40 cm) and is better suited to naturalising in a woodland garden setting than as a formal border grass, but it is very hardy, self-seeds gently, and provides attractive movement and texture in shaded conditions. The important caveat is that melica species prefer partial shade with adequate soil moisture rather than deep, dry shade; in very dry, deeply shaded positions under large trees with highly competitive roots, melica can struggle as much as other grasses.

Q: How do I grow melica in the UK?

Melica altissima and M. transsilvanica grow best in partial shade to dappled light in moderately fertile, well-drained but reasonably moisture-retentive soil; they are versatile grasses that tolerate a range of conditions from lightly shaded to quite sunny positions as long as the soil does not dry out completely in summer. In full sun in dry soil, supplementary watering is needed through summer; in partial shade in moist soil, they are largely self-sufficient once established. Plant from spring to early autumn; space at 40 to 60 cm for specimens, 30 to 40 cm for a naturalistic drift. Water consistently through the first growing season to establish the root system. Feed with a balanced general-purpose fertiliser in spring to support the attractive flower display. Cut back the entire clump to 5 to 10 cm in early spring (February to March) before new growth begins; melica is a cool-season grass and begins growing in late winter and early spring before many warm-season grasses are active. The attractive flower spikelets appear in May to July; allow them to dry on the plant for as long as they remain ornamental as the dried spikelets persist attractively through summer. Melica species self-seed relatively freely; deadhead after flowering if self-seeding is not wanted. They are generally free of significant pests and diseases in UK conditions. Melica uniflora (wood melic) is best left to naturalise freely in a woodland garden setting rather than being managed as a formal border grass; it seeds itself gently and fills gaps between larger plants attractively.

Q: Does melica go dormant in summer?

Yes, some melica species — particularly the smaller-growing ones including the native UK Melica uniflora — go through a period of partial or complete summer dormancy in the hottest and driest part of the UK summer, typically July to August; the foliage browns, the plant looks dishevelled or even apparently dead, but it regenerates reliably from the crown in late summer and autumn when temperatures drop and rainfall increases. This summer semi-dormancy is the normal lifecycle of these cool-season woodland grasses, which grow most actively in the cooler, moister conditions of spring and autumn. Melica altissima and M. transsilvanica are somewhat less prone to dramatic summer dormancy than M. uniflora, particularly in partial shade with reasonable moisture, but they may also look less fresh in midsummer than in spring and autumn. In a hot, dry UK summer, browning from summer dormancy in melica is normal and not a sign of a permanent problem; resist the temptation to water heavily (which can promote root problems) or to cut back during the dormant period. Wait for the cooler, wetter conditions of late August and September, when the plant typically produces a flush of fresh new growth, and cut back tatty summer foliage at that point if needed.

Melica (melic grass) includes some of the most useful ornamental grasses for partially shaded UK gardens, particularly Melica altissima (Siberian melic) and M. transsilvanica, with attractive one-sided flower spikelets from May to July. Cool-season grasses that grow most actively in spring and autumn. Drought and full sun in dry soil cause leaf curl; summer semi-dormancy in hot dry conditions is normal.

Drought stress

Melica prefers moderately moist, partially shaded conditions; in full sun in dry, light soil in a hot UK summer, the broad flat leaves curl along their length and brown at the tips. Newly planted specimens and container-grown plants are most vulnerable. The combination of full sun and dry soil is the worst growing condition for melica and reliably produces curling and browning; the same plant in partial shade with the same soil moisture thrives.

What to do

Move to a partially shaded position in moderately moist soil; a north or west-facing border, a woodland garden position, or the shaded side of a structure in moist soil all work well. If the position must be sunny, improve moisture retention by mulching with bark and watering consistently through summer dry spells. Melica is more tolerant of sun than many purely woodland grasses as long as the soil does not dry out completely.

Summer dormancy

Melica species, particularly M. uniflora (wood melic), go through a period of semi-dormancy in the hottest and driest part of the UK summer (July to August); the foliage browns and the plant looks dishevelled or apparently dead. This is normal cool-season grass behaviour and not a sign of a cultural problem. The plant regenerates from the crown in late summer and autumn when temperatures drop and moisture increases.

What to do

Leave the plant undisturbed through the dormant period; do not water heavily (which can cause root problems) or cut back during summer dormancy. In late August and September, fresh new growth appears and the plant can be tidied at that point if the summer foliage is unattractive. In partial shade with moderate moisture, M. altissima and M. transsilvanica typically show less dramatic summer dormancy than M. uniflora.

Deep dry shade

Melica prefers partial shade but does not perform well in very deep, dry shade — such as under large dense-canopy trees with highly competitive root systems where both light and soil moisture are severely limited. In deep dry shade, melica produces thin, pale, curling leaves rather than the broad, glossy, upright leaves of a well-grown specimen in dappled light with adequate moisture. The combination of darkness and drought suppresses growth rather than the shade alone.

What to do

Choose positions with dappled or partial shade (sunlight reaching the ground for some of the day) rather than solid deep shade. Improve soil moisture in dry-shaded positions by mulching heavily with bark or leaf mould and watering through the first two growing seasons until established. In deeply shaded positions with very dry, root-dense soil under large trees, even shade-tolerant grasses including melica will struggle; Deschampsia cespitosa is a better option for the deepest, most difficult shade.

Frequently asked questions

Why are my melica leaves curling?

Melica leaves curl most commonly because of drought stress in a sunny or dry position (broad leaves curl and brown at the tips; move to partial shade in moist soil; mulch; water in dry spells), summer semi-dormancy in July and August (normal for cool-season woodland grasses; foliage browns; regenerates in late summer; do not overwater during dormancy), or deep dry shade under trees (thin, pale, curling leaves; needs dappled light and moisture, not just shade). Partial shade in moist soil is the ideal position.

Is melica a good shade grass for UK gardens?

Yes; melica species are among the most useful ornamental grasses for partially shaded positions where most sun-loving grasses won't perform. M. altissima and M. transsilvanica are reliable in dappled or partial shade in moderately moist soil, producing attractive one-sided flower spikelets from May to July. M. uniflora (wood melic) is a UK native best naturalised in a woodland garden setting. All three need dappled light and moderate moisture rather than deep, dry shade.

How do I grow melica in the UK?

Grow in partial shade to dappled light in moderately fertile, well-drained but reasonably moisture-retentive soil. Plant 40 to 60 cm apart. Water through the first season. Feed with balanced fertiliser in spring. Cut back to 5 to 10 cm in February or March before new growth begins. Allow flower spikelets to dry on the plant through summer; deadhead if self-seeding is not wanted. Generally free of significant pests and diseases. M. uniflora is best left to naturalise freely in woodland settings.

Does melica go dormant in summer?

Some melica species, particularly M. uniflora, go through partial or complete summer dormancy in the hottest, driest part of the UK summer (July to August); the foliage browns and looks dead but regenerates in late summer and autumn. This is normal cool-season grass behaviour. In partial shade with reasonable moisture, M. altissima and M. transsilvanica show less dramatic summer dormancy. Leave the plant undisturbed through dormancy; tidy in late August to September when fresh growth appears.