Grasses in the Landscape

by Liz Hamilton

On a recent trip to the UK I found that the fashionable English country gardener is experimenting with grasses in the landscape. Looking for more fall color in my gardens, and added winter interest I thought this idea would transfer over to Colorado rather nicely. Here is an excerpt from an article in a English gardening magazine -with some editing of plants for our own climate. Thinking that adding more grass to the garden might just fool the elk! - Yeah right!!!

There was a time not so long ago, when if you planted grass in the garden, anywhere other than the lawn, you were considered a maverick or worse. But times have changed and if your borders do not include at least a few ornamental grasses, you cannot hope to be fashionable and might as well go shopping for flares and a tank top. In fact, many would have us believe that the way to garden is to fill beds with grass and have a few flowers popping up between. Without going to any extreme it is good that most gardeners are at last realizing that grasses have their place in the garden and that they can provide an elegance and movement unlike any other plants. Their foliage contrasts so well with most herbaceous plants and their delicate flowers catch the light and glitter in the sun, offering a contrast to bolder blooms in the same way that gypsophila is the perfect partner to sweet peas in a vase.

If you want something other than green, grasses can provide yellows, blues, browns and even red – more than enough for even the most adventurous gardeners. From the horticultural point of view, the term grass includes true grasses as well as the related sedges and rushes. What they have in common is a tufty habit, with narrow foliage and flowers that are generally insignificant but attractive through their sheer numbers, arranged on airy spikes. Within this range they vary considerably, from the tiny festuca to giants such as miscanthus that makes a great sheaf of foliage, topped by fluffy flower heads in late summer. Most of the popular grasses are hardy perennials but there are annual grasses too and these really do look lovely when mixed with hardy annuals to make a naturalistic summer meadow. The most unusually, yet familiar of the groups of grasses are the bamboos. These are woody plants with upright canes and elegant foliage. Although some are invasive most of those commonly on sale are well behaved and make beautiful clumps. They are essential for a pond area and many are happy in pots.

Bamboos: Pandas love bamboo, and some garden designers are addicted to them. As gardeners we should try to use them more often than we do. In general they are hardy, and distinctive and tolerant of the wind. Though they look superb next to water they will not grow well in wet soil and they do not like a drought either, especially as young plants. Check the height of bamboo when buying it and place it appropriately. Canes grow to their ultimate height in the first year, then sprout leaves from side branches in future years. If a variety is too tall for the area it is not easy to restrict it without spoiling its elegance. Remember that the canes are as much a feature as the leaves and there are bamboos with golden, lack, green spotted and even stripped canes.

  • Pyllostachys aureosulcata ‘Spectabilis’ is a bold, tall bamboo with dark, glossy leaves and dark green stems that are stripped with gold. Reaching 20 ft or more, it makes a bold statement in the garden.
  • Phyllostachys nigra is of similar size. The canes are dull green in the first year but mature to shiny black and in P. aurea they are golden yellow.
  • Pleioblastus auricomus and Shibataea kumasasa are both pretty for ground cover where they create a weed free mat 2-3 ft height.

Containers: Grasses are wonderful container plants but look best planted with one kind per pot. Then grouped with other grasses and other plants to change the display. Match the grass with the pot and have fun. Use a soil based compost. Suitable grasses, with a neat habit include:

  • Acorus gramineus ‘Ogon’
  • Hakonechloa macra ‘Aureola’ – Graceful, slender, leaning or arching stems. Effect is that of a tiny bamboo. Needs shade, good soil, average water.
  • Arundo donax versicolor - Tall reed-like grass needs cover in the winter, plant in a container, and bring inside the garage in the winter. Needs lots of water in the summer, and can be invasive if grown directly in the garden.

Prairie Planting: Areas filled with grasses mixed with flowers that naturalize together. Great to use in a sunny area with poor soil. Suitable flowers to mix would include helianthus (sunflowers), achilea (yarrow) Echinacea (purple cone flower) etc.

Grasses for prairie areas:

  • Agrioyrin pubifloru, (Elymus magelanicus)- with steely blue foliage.
  • Festuca gluca at the edge of beds. ‘Golden Toupee’ is bright yellow in contract to the steely blue of ‘Blaufuchs’ (‘Blue Fox’)
  • Miscanthus sinensis form neat clumps but ‘Kleine Silberspinne’ is small and feathery.
  • Molinia caerulee - ‘Variegata’ has prettily yellow edged leaves. ‘Transparent’ has erect flowers spikes that are, as the name suggests, see-through.
  • Pennisetum alopecuroides forms fountains of pretty flower head tinged with pink and is best in a warm, sunny spot.

Annuals: Add a few annuals to your bedding to give a light, airy contract. They can be sown in cells and planted out in May, or June or sown where they are to flower. Or combine them with hardy annuals such as cornflowers and poppies for a tame, wildflower meadow. They are also great for cutting and drying. Some of the best annual grasses include:

  • Agrostis nebulosa – is just a puff of fluff, this creates a fog of flowers and is superb
  • Briza maxima is the quaking grass and has large, pendant seed heads, perfect for drying
  • Lagurus ovatus, the rabbit’s tail grass is the cutest of all

Waterside: If you have a pond you will want to try a few grasses. Their wavering stems and foliage are so restful and their stems make ideal resting places for dragonflies and birds. Plant them in aquatic baskets and place on the pool shelf so they are kept constantly moist.

  • Acorus gramineus ‘Ogin” - not strictly a grass but it has the look. It makes neat fans of yellow stripped foliage that are evergreen.
  • Cyperus longus is hardy yet looks exotic with parasols of leafy bracts on tall stems.
  • Juncus effussus ‘Spiralis’ is one for the gardener that likes the strange. The bright green, leafless stems are curled into the ‘perm from hell’.

Sunsets ‘Western Gardener Book’ offers a wealth of information on plant options and is a great resource for Bamboo planting.