When it comes to ornamental grasses I am at risk of hyperbole with almost every utterance. But there is one grass that really does rank among the finest of all garden plants - Stipa gigantea, the golden oat grass.
Ornamental grasses bring texture, form and sound to the garden; Stipa gigantea delivers on all of these in spades. The low clump of foliage, 45 to 60cm (18 to 24in) tall, comes into flower early in the season, from late May or early June, with stout, well-spaced flowering shoots with light-green stems. In summer golden oat-like flower panicles appear, held aloft on stems 180 to 240cm (6 to 8ft) high. The inflorescence start with a purplish green tinge, before turning to the rich colour of old gold, and look spectacular when back-lit with the warm clear light of the evening sun.
In a summer breeze the whole plant seems to shimmer and, with eyes closed, one could easily imagine that the sound of the wind passing through its stems is actually the sound of blue sea lapping on golden sands. By late July the seeds have fallen and for many flowering plants this would be the point at which they began to fade into the background. But the golden oat grass is only just beginning a long period of interest and beauty, for the empty seed carriers persist on the plant right the way through into winter.
Stipa gigantea has the wonderful and fashionably transparent quality of providing height without bulk, as its stems allow glimpses into the garden beyond. It excels as a specimen plant, rather than planted in large blocks. Using single plants, or groups of three, planted repeatedly through a border is very effective. Its see-through qualities mean that it can be placed near the front of the border.
The plants need to be positioned correctly to be fully appreciated, even more so than other grasses, early morning and late afternoon sunlight striking this grass illuminates it to dramatic effect.
- Awarded the RHS Award of Garden Merit
Stipa gigantea was awarded the Royal Horticultural Society’s Award of Garden Merit (AGM) in 1993.
Sowing: Sow indoors in spring to early summer
Stipa seeds are best sown from February to July. Use good, well drained seed compost, sow small seeds finely in trays and sow large seeds in cells or small pots. Sow in the surface and cover lightly with a very fine layer of sieved soil
Place in a propagator or warm place to maintain an optimum temperature of 15 to 18ºC (60 to 65ºF). Germination may occur quickly in 2 to 4 weeks, but can be slow and erratic and may take several months. Stipa seeds can be sown at other times of year, but will need more patience as germination will be slower.
Seeds may benefit from the cold treatment of stratification. After sowing, seal the container in a polythene bag and leave at 15 to 18ºC (60 to 65ºF) for two weeks, then place in a refrigerator (not freezer) for 3 to 6 weeks. After this, return to the recommended germination temperature, if germination does not occur in 6 to 10 weeks, return to the fridge for a further 3 to 6 weeks. Examine regularly whilst in the fridge and remove immediately the seeds show signs of germinating.
After germination occurs, keep seedlings in cooler conditions to grow on. Transplant when large enough to handle into 7.5cm (3in) pots containing a gritty compost. Germination to transplant usually takes around four to six weeks. Plants in containers should be looked after carefully and not allowed to stand in full drip trays.
They will form a bushy plant and be ready to go into the garden in summer. Once large enough to be planted outdoors, acclimatise the young plants to outdoor conditions before planting out after all risk of frost.
Grow in full sun and in well-drained soil. The flowers of this grass spread much wider than the plant and so a spacing of at least 1.5 metres (4.5ft) is advisable. The inflorescence rise dramatically above other perennials or shrubs.
Ornamental grasses are pretty much bullet-proof as far as pests and diseases go. Few require special treatment or pampering to perform, so they should be near the top of the list of plants to use for anyone with limited time to lavish on their garden. Stipa gigantea is no different, providing it is planted in a sunny spot and in well-drained soil.
It will tolerate almost any well-drained soil conditions; it will be happy at neutral, alkaline or acid pH levels, in loam, sand, chalk or clay based soils facing any sheltered or exposed aspect. It is hardy to at least minus 18°C (0°F) and drought tolerant once established.
Because it's a plant of rough and rocky places there is no need to feed or fertilise Stipa gigantea. Once established it should not need additional water, even in the hottest of summers.
Always wear stout gardening gloves to protect against the sharp edges of the basal leaves. Maintenance is straightforward: cut the flowering stems back to the main clump in spring and, wearing gloves, comb through the plant in early spring to remove dead foliage. Lightly trim the foliage if starts to look tatty.
In the right conditions the golden oat grass will bulk up quickly into a decent-sized clump, which can be lifted and divided every three to four years, from spring until early summer.
The flower heads can be dried and make interesting focal or secondary flowers in dried arrangements. To dry, cut the flower at the height of bloom and hang upside down in a cool, dark place to dry.
Perennial Borders, Matrix Planting, Naturalistic planting schemes, Flower arrangements, Low Maintenance, Containers, Specimen plant. Coastal.
Stipa gigantea, commonly known as Golden Oats or Giant Feather Grass, is native to Western Europe and has been naturalised in some parts of the UK.
Stipa gigantea can be found growing wild throughout southern Spain, Portugal and northern Morocco, where it thrives in the sharply drained, stony soil of the scrub-covered hillsides and valleys. It is well adapted to these difficult conditions - the reduced surface area of these narrow leaves limits transpiration. Its growth habit helps: a low clump of foliage, topped by stout, well-spaced flowering shoots that let strong drying winds pass through without tearing the plant from the ground.
The genus name Stipa is derived from the Greek word stuppeion meaning 'fibre' in reference the use of fibers of the species Stipa tenuissima to make rope.
The species name gigantea is derived from the Latin meaning ‘very large’. It appropriately describes the tall flowering stems.
Pronounced STY-pah jy-GAN-tee-ah. It is commonly known as Golden Oats, Golden Oat Grass, Giant Needle Grass, Spanish Oats and Giant Oats
- Awarded the RHS Award of Garden Merit
- Additional Information
Average Seed Count 15 large seeds Common Name Golden Oats Other Common Names Golden Oat Grass, Giant Needle Grass, Spanish Oats and Giant Oats Family Poaceae Genus Stipa Species gigantea Synonym Macrochloa arenaria Hardiness Hardy Perennial Flowers Purplish-green maturing to pale gold Natural Flower Time June and July Height Foliage 45 to 60cm (18 to 24in), Flowers 2m (6ft) Spread 60 to 90cm (24 to 36in) Position Full sun or partial shade Soil Moderately fertile, medium to light, well-drained soil.
It will tolerate damp but not waterlogged.