Tough and versatile, there are decorative grasses and bamboos for sunny or shady locations and dry or damp soils. Select them carefully to produce a year-round display of foliage, flowers, stems, and seedheads.
Grasses are a varied group and can be found on every continent on the planet; those selected for garden use have graceful styles and decorative flowers and seedheads. They range from tiny types, such as the squat fescues, to towering giants like Arundo donax, which reaches up to 12 feet in height. Most grasses prefer full sun and free-draining soil, although Holcus, Milium and the prairie cord grass, Spartina, thrive in moist conditions and some shade. Most bamboos and the evergreen Carex family and other sedges, which closely resemble grasses, are also perfect for shady sites and damp soils. Buy bamboos and grasses from a reputable nursery that can offer expert advice on the conditions your chosen varieties prefer.
Selecting Well-Behaved Bamboos
Bamboos are simply grasses that form woody stems, and they tend to be more tolerant of shady conditions than their close relatives; a few, including forms of Pleioblastus, are even happy in deep shade. They thrive in moist but well-drained soil.
Despite their elegant appearance, some bamboos have a dark side—their invasive, spreading roots can take over a garden, transforming beautiful planting designs into dense jungles. Bamboos that fall into this group include Indocalamus, Pleioblastus, Pseudosasa, Sasa, and Sasaella. If you want to grow these, restrain their roots by planting them in large containers or raised beds.
Clump-forming species, such as Fargesia, Chusquea, Thamnocalamus, Himalayacalamus, Phyllostachys, and Semiarundinaria are better behaved, but will still benefit from a root guard to keep them in check. Consider these types of bamboo for your garden:
- Phyllostachys: One of the most popular tall, clump-forming bamboos. Choose from golden-, black-, or green-stemmed types; all are ideal for use as screening or as focal points.
- Thamnocalamus: A tall, graceful bamboo that is a beautiful garden specimen. It has small leaves and either blue, fading to deep red, or pinkish-brown stems.
- Fargesia: All members of the Fargesia family are well behaved, hardy, and tolerate dry soils. They make excellent hedges and look stunning when grown in large patio containers.
- Borinda: This non-invasive bamboo is closely related to Fargesia and Thamnocalamus. Its vivid blue stems and strong upright growth are a colorful focal point or screen.
Among the most alluring features of decorative grasses are their seedheads, which can grace a garden from midsummer to winter if you mix and match varieties, and are especially valuable during the winter months when there is little else to see. Choose a variety of different types, such as feathery plumes and caterpillarlike brushes.
The best grass choices for winter-interest seedheads include forms of Stipa, Pennisetum, and the reed grasses, Calamagrostis, as well the larger grasses, such as pampas grass (Cortaderia) and the many forms of Miscanthus. You can learn more details about these seedheads below:
- Stipa calamagrostis: The feather grass is so named because in late summer it forms beautiful plumes of greenish-white flowers, shaped like giant feathers. These then dry to produce tawny seedheads that last through the winter.
- Pennisetum alopecuroides: In late summer the fountain or foxtail grass bears long stems of pinkish-brown, foxtail-like flowers that dry to form decorative seedheads. It needs a sunny, sheltered site to survive the winter.
- Briza: Both the annual B. minor and perennial quaking grass, B. maxima, produce spear-shaped seedheads that dance in the breeze during summer and fall. Plant in full sun and any soil — even in wet conditions.
When and Where to Plant
Most grasses, sedges, and bamboos are available in pots and can be planted like perennials at any time of the year, unless the soil is frozen, very dry, or waterlogged. However, it is best to plant them in the spring, allowing a full growing season for them to establish before winter. Some bamboos, especially those used for hedging, are also available as bare root plants in the winter; plant them as soon as you receive them. Grasses suit most sunny mixed borders and gravel gardens, and they also make effective container plants. Bamboos will be happy in both sunny and partially shaded areas and are best used as focal points or backdrops to mixed planting designs or to create a screen or hedge. Most grasses and bamboos dislike waterlogged soils, so add horticultural grit to heavy clays to improve drainage, and incorporate plenty of well-rotted manure or garden compost into all types of soil a few weeks before planting.
Two for One
Grasses are very easy to divide, and if you buy a large clump in a pot, you can instantly make two smaller plants. Since grasses bulk up pretty quickly, this can be an economical way of filling a border. To divide your grass, tip it out of its container, and then either pull the root ball apart with your hands, or cut it with a sharp pruning saw. Plant the divided sections immediately in moist compost in a container or in the ground.
Aftercare and Maintenance
Grasses rarely need extra irrigation once established because they have adapted to survive periods of drought. Bamboos may need watering for longer and will need a constant supply of water if grown in containers, so you may want to invest in an automatic system, such as a seep hose or drip nozzles attached to a hose pipe. An automatic timer will also allow you to regulate watering times.
Apart from watering, bamboos and grasses require very little extra maintenance. In spring, comb out the dead growth from evergreen grasses and sedges with a spring-tined rake or kitchen fork. The dead stems of deciduous grasses have decorative value in the winter, but should be cut back in the spring.
Cut out dead bamboo stems when you see them, and mulch plants every year in the spring with rotted manure or composted bark. Leave a carpet of dead foliage beneath the plants. This contains silica, which bamboos need in order to form wood.
Bamboos spread via underground root systems or rhizomes that travel horizontally just beneath the soil surface, throwing up new stems as they do so; some can be invasive. To prevent them from taking over, dig a narrow trench around your clump, and insert a commercial root barrier of non-perishable material, such as strong plastic or a wall of slate slabs. Alternatively, use a sharp spade to slice through the roots around your bamboo, and dig out and remove the severed roots. Automate watering to ensure that plants receive enough water to establish successfully.