There is a “growing” trend toward using groundcovers to reduce the need for bark mulch in gardens. As with any trend, there is a time and place where it is appropriate, and other times when it is not. One plant that we absolutely love for that purpose is the evergreen Carex flacca ‘Mini’. This blue-foliaged sedge is a Mediterranean native marsh grass that spreads very slowly, so it is not a problem in overrunning other plants in the bed, as long as they aren’t placed too close. These pictured below were planted six years ago on 1′ centers, and are just now knitting together.
We have studied a few reports of this sedge being invasive in parts of the northeast US, but our trials have shown quite the opposite, with nary a seedling in over six years. We can find no scientific research that shows this sedge qualifies as being invasive using any commonly recognized definitions of an invasive plant. Our skepticism of these reports comes because some of the ridiculous listings that appear on invasive species lists, which have no scientific basis. Our favorite invasive faux pas was a listing a couple of years ago of the genus Bambusa on a state invasive list. Never mind the plant is a strict clumper and only flowers once every 100 years. Winter hardiness is Zone 4-9.
We’re always looking for more “green mulch” plants, which cover the ground, reducing weed pressure, while not choking out desirable plants. One such plant we feel should be more widely grown is Erigeron pulchellus. This amazing perennial is native to every state east of the Mississippi River. So, why isn’t it grown in every garden? Inquiring minds want to know. The rosettes lay flat on the ground, but are topped right now with short 8″ spikes of blush pink daisies. Our photo from the garden this week is the clone Erigeron pulchellus ‘Lynnhaven Carpet’. Erigeron pulchellus is easy to grow in average soils in light shade to part sun.