This would be a great time to get a new ground cover bed started. Nurseries have good supplies. You’ve caught up with most of your spring gardening activities. Evenings are longer. I’m convinced. Aren’t you?
Why we use ground covers
There are those who turn to ground covers with the mistaken idea that they’re less work than turfgrass. “I’m just tired of mowing and dealing with weeds,” is what they say. But the truth of it is that lawngrasses are actually the lowest-maintenance ground-covering plants that we grow.
So why would we want to use ground covers? I can think of three valid reasons. First, we want something different – a transition between low shrubs and turfgrass. Second, we have an area where it would be difficult to maintain turf. Examples might be long, narrow spaces or particularly steep slopes. Third, and very commonly, we can’t get grass to grow because there’s too much shade.
Good bed preparation is key
So let’s assume you do decide to put this group of plants to work in your landscape. Your ground cover planting will only be as good as the bed you prepare for it. Follow these steps carefully.
• Carefully lay out your bed. If it’s a new area, use a flexible garden hose to create an interesting design. If you’re planting in the shade of a tree, it will look more natural if you don’t create a perfectly circular bed using the trunk of the tree as your bulls-eye.
• Eliminate all existing grasses and weeds. In most cases an application of a glyphosate-only herbicide (no other active ingredients) will do the best job. Glyphosates kill grasses and most broadleafed weeds without contaminating the soil. You need to allow them 10 to 15 days to do their work before you disturb the soil.
• Rototill to a depth of 6 or 8 inches. If you’re working beneath shade trees, carefully note where major roots are and do your best not to damage them. If you have to rototill to only 2 or 3 inches because of shallow roots, you can still make it work.
• Incorporate 1-2 inches of compost or finely ground pine bark mulch to help loosen clay soils and to help sandy topsoils hold moisture and nutrients. Rototill again. If you’ve heard about the perils of adding topsoil over the root systems of established trees, this organic matter doesn’t count. It won’t be a problem.
• Rake to a smooth grade. As you’re planting, try not to leave footprints and depressions.
Choosing your ground cover
Any plant that stays low enough to allow a clear line-of-sight across your landscape would qualify as a “ground cover.” It might be a low herbaceous plant that only grows to 2 or 3 inches, or it could be a very low shrub that stays at 2 feet. It all depends on the setting. Here are a few good ones to consider. I’ll list them in order of increasing height.
Dwarf mondograss grows to 3 inches tall. It’s clump-forming, deep green and evergreen. It’s too slow to be used for large areas, and it’s also subject to crown-rot problems in waterlogged soils. Shade.
English ivy grows to 6 or 7 inches tall, and it spreads by trailing vines. It’s evergreen, and it requires shade from mid-morning on. Give it perfectly draining soil.
Asian jasmine is the longtime favorite full sun or part sun ground cover for Texas. It has glossy, dark green leaves. It’s evergreen, although it frequently suffers freeze damage in North Texas. It spreads by runners and becomes 8 to 9 inches tall.
Purple wintercreeper is replacing Asian jasmine as the full sun to part sun ground cover of choice. Its leaves are deep green in summer, turning maroon in the winter. It spreads by sprawling runners. It grows to 8 to 10 inches tall.
Mondograss is the best of the shade-loving types. It grows to 8 to 10 inches tall. It has fine-textured foliage that is deep green. Its flowers are inconspicuous. Leaves are easily blown out of it in the fall. It’s excellent at holding soil on slopes.
Liriope is the big sister to mondograss. Its leaves are wider and its texture is bolder. It produces lavender or white flower spikes in the summer. It grows well in shade, and it tolerates a bit more sun than mondograss. Mature height depends on variety, ranging from 14 to 18 inches.
Dwarf nandinas including varieties Flirt, Harbor Belle and Harbour Dwarf are all very low-growing types that stay at 18 to 20 inches tall. They can be kept shorter by removing a few of the tallest canes completely to the ground once or twice annually.
Planting your ground cover
Most of the types listed will be sold in 4-inch and gallon containers. Plant trailing types 14 or 15 inches apart. Hopefully the plants will be large enough that the ends of their shoots will touch as you plant them.
With regular mondograss and liriope, either plant 4-inch pots intact or cut or break very full gallon-sized clumps into two or four pieces and checkerboard them on 8- or 9-inch centers, closer if you’re trying to hold soil on a slope.
The secret in getting your ground cover to cover as quickly as possible, hopefully within the first two growing seasons, will be to keep the bed moist at all times, apply nitrogen fertilizer every six weeks spring through early fall and keep weeds pulled out. You’ll be pleased with how quickly the plants will respond.