Most gardeners are familiar with ground covers that are the “creepy, crawly” type, – those that hug the ground and form a thick mat on the soil surface. There is another category of ground covers, however, that is just as useful in the landscape and the good thing about this group of plants is that they are good old standbys that are often easily obtained from a neighbour free of charge. Often called “spreaders,” these plants are easily propagated by division so it is quite possible your neighbour will be only too glad to give you a shovelful of any of these plants.
I call these plants tall ground covers because when we think of ground covers we invariably think of the mat-forming kind. These perennials, however, grow quite tall and some of them bloom in abundance. They spread rapidly to completely fill the spot they are in so care must be taken not to plant them where their invasive nature might create a problem. One is bishop’s goutweed, which can be grown in full shade or full sun. This tough, versatile perennial will thrive in the most inhospitable surroundings and is often used to fill in trouble spots or to create beauty on the north side of a building where nothing else seems to want to grow.
Bishop’s goutweed has variegated white and green leaves and grows about 35 cm tall. All summer long the area in which it is planted is completely covered with its wonderful foliage, which stays attractive well into the fall. The plant does put forth rather nondescript small, white flowers that are held above the foliage on sturdy stems. These can be removed if desired. This is a perfect ground cover for shade areas as the white in its foliage can brighten up a dark corner.
Common yar row, which comes in a variety of pink shades, is another useful ground cover. It also spreads quickly to completely occupy its allotted space, its ferny foliage creating a thick clump. The stems are about 70 cm tall and the blooms are very long lasting – it often blooms from mid- June until late August. When the plants become leggy or unattractive for any reason, they can simply be sheared almost to the ground. The foliage will be rejuvenated and before long there will be a solid mat of attractive, ferny foliage. In some southern areas of the U.S. where rainfall is scarce, gardeners use yarrow instead of grass for lawns and simply keep it mowed. It is extremely drought resistant.
The same method can be used for another tall ground cover, clustered bellflower. This is a common garden plant – “weed,” some would say, but it does have its uses. It will fill in trouble spots because it too is very tough and versatile, adjusting to all but the most inhospitable locations. After its large umbrels of dark-purple flowers have finished by late June, the plants can be mowed and used as ground cover for the rest of the season.
Nepeta (catmint) makes a good ground cover. It will spread by underground roots and by seed and grows about 45 cm tall. Its bright-mauve blooms persist for a long time and if it is sheared back in midsummer, it will put forth more stems and rebloom in the fall. It is quite a fragrant plant and the spikes of bloom attract bees and butterflies. Many gardeners use it as an ordinary perennial in their borders, but it can be an effective ground cover as well.
I have also seen daylilies, especially the species type – the old buff-coloured ones that grow in the ditches in some areas of Manitoba. This plant cannot be cut back during the growing season, but its grassy foliage and continuous bloom will stay attractive all summer while it covers completely the area in which it is used. There are usually some areas of our landscapes that we just want to cover without a lot of thought about design or contrast. We simply want plants that will completely fill in a spot to make it relatively maintenance free. Some of these tall perennial ground covers fill the bill perfectly.
– Albert Parsons writes from Minnedosa, Manitoba