Grasses

Adding texture in a mixed border

Ornamental grasses are suited to almost any kind of garden, from traditional to modern, from city to country. Grasses can be the solution to a number of gardening problems. They can add color, texture, movement and even year round interest. A single specimen can be used as an accent plant or planted in mass for more of an effect. They can even be used in groups as a screen. Most grasses don’t interfere with other plants.

Blue Oat Grass and Japanese Blood grass

As a color accent they come in green, yellow, blue, variegated and some with red tints. We use a lot of yellow here at Old Goat Farm so I seem to be drawn to those first. We have used Hakonechloa macra ‘Aureola’ and ‘All Gold’, the Japanese Forest Grass, quite a bit in the shade garden. In the sun Carex elata ‘Bowles Golden’ has a similar effect. For a blue accent in the sun Helictotrichon sempervirens, the Blue Oat Grass, is a real stand out. Too many come in green to single out just one or two. Andropogon gerardii ‘Red October’ starts out green but in fall turns a nice shade of red. Imperata cylindrica ‘Red baron’, the Japanes Blood Grass, has red tips throughout the growing season.

When planting, work the soil deeply, incorporating organic material as available.You can add general-purpose fertilizer (such as 10-10-10) during soil preparation of planting bed. You should plant to the same depth they were planted before because ornamental grasses do not like to be planted too deeply and may develop root diseases or rot. Like any new plant, water ornamental grasses and keep well watered until they settle in, usually the first season. They may need a bit of water during a drought. Ornamental grasses require relatively low levels of fertility. We don’t add any extra fertilizers other than our annual composting. Too much nitrogen can lead to flopping.

We also leave most of our grasses stand through most of the winter for a couple reasons. Many look good and give structure to the garden in winter and also the seed heads provide food for the birds. Cutting back early can expose the crown and here in the northwest may subject the plant to crown rot. We do cut them back to about six inches before the new growth begins. Some of the evergreen varieties we clean up in the spring by just raking out the old growth that has turned brown. Some evergreen varieties are not long lived so will need to be replaced. Blue Oat grass for one does not respond well to being cut back hard. Carex morrow ‘Ice Dance’, on the other hand, can be cut to the ground every few years to renovate it.