Ornamental Grasses are becomming more and more popular and are super for providing structure to your plantings.
Grasses are like other herbaceous perennials: their flower stalks can be cut off or allowed to go to seed.
The spent flower stalks of grasses, whether evergreen or deciduous, keep their structure well so are often left uncut over winter, and only removed early the following year. The stalks may be bleached of colour but still provide height, structure and movement in the garden when most perennials are invisible.
They look beautiful covered with hoar frost, and winter wildlife appreciates both the shelter they offer and the food the seeds provide for birds and small mammals.
A few great garden Grasses.
Cortaderia selloana ‘Pumila’ Pampas grasses have been much maligned, but this smaller cultivar is elegant and mixes well with other perennials and shrubs. Height: 1.5m (5ft).
Festuca glauca ‘Elijah Blue’ One of the bluest of fescues, ‘Elijah Blue’ forms a spiky dome. Trim back every few years in March to get rid of dead leaves. Height: 40cm (16in).
Miscanthus sinensis ‘Morning Light’ A compact cultivar with slim cream margins to its leaves, this miscanthus is ideal for small gardens and even containers. Height: 1.5m (5ft).
Pennisetum villosum The fluffy rabbits-tail-like seedheads of this grass are an instant attraction. Not the hardiest: needs sun and free drainage for the best results. Height: 60cm (2ft).
Stipa tenuissima The fine blades of this grass dance even in light winds. Cut back in spring for fresh green growth, which ages to soft gold by late summer. Height: 60cm (2ft).
How to Divide Grasses
Grasses from cool climates such as Deschampsia, Festuca, Helictotrichon and Stipa come into growth in late winter and flower before mid-summer.
They are divided in autumn or late winter to early spring. It is often preferable to divide frequently to avoid the difficulties of congested roots and to keep plants growing vigorously.
Grasses from warm climates such as Miscanthus, Panicum, Pennisetum and Spartina come into growth in late spring, flower after midsummer and are usually cut back in late winter. They are best planted or divided in late spring. These grasses do not usually need such frequent division.
The best method for division is to lift grasses from the ground and split using two forks inserted back to back in the centre of the clump or split through the middle with a spade. Some grasses have tough roots that may require using a sharp knife, saw or even an axe to split them apart. Small grasses such as Hakonechloa, and many sedges, can be split by tearing lifted clumps apart by hand. Cut down the foliage of pampas grass before dividing - making sure you wear stout clothing and gauntlet-style gloves. Keep pieces as large as possible in most cases