Garden Notes

Karl Foerster grass growing in perennial border

I love the look of the various grasses and I especially like the way they add movement to the garden. Unfortunately, many grasses are too aggressive for the home garden and eventually they become weeds. Not so with Karl Foerster. It is a perennial clumping variety of grass that stays put and does not send out roots that try to take over the world.

Awarded the title of Perennial Plant of the Year 2001, Karl Foerster is one of the most versatile, attractive, and low maintenance ornamental grasses. The deep green, shiny foliage of this cool season grass appears in early spring and lasts until early winter. It’s feathery flowers appear in June and initially they appear a light pink. As the seed heads mature, they become wheat colored and last through fall.

In my garden Karl Foerster reaches about 5 feet tall and the vertical grass clump is about 16-inches wide. After trying out Karl out for a couple of years, I recently added four more clumps to add height to a sunny section of the perennial border. I found Karl Foerster grass to be pretty carefree. I just planted my starter clumps and they grew into tall beautiful specimens without any special fertilizer or extra care. Also of note, I have not seen any pests bothering this grass which is important to me because I am not patient woman. I have disposed of more than one plant that refused to thrive. I generally give a new plant about 3 years. Then, if it is still limping along looking pathetic, it becomes compost.

Research says that Karl Foerster grass grows best in well-drained fertile soils with sufficient moisture, but will tolerate heavier clay soils and drier sites. Little maintenance is required except to cut back the stems to about 6 inches in late winter or early spring which I always do. This is a cool-season grass, so planting or transplanting in spring or fall is best. Sterility eliminates any chance of this cultivar becoming an invasive plant or creating unwanted seedlings in the garden. It is hardy in zones 4-9.

I find Karl Foerster attractive in summer, especially after it heads out and it only becomes more beautiful as the summer goes on. Then when the snow flies and the garden goes to sleep, it adds winter interest. I think it is the perfect grass for my garden!