Question: What groundcover can I use to cover my tree’s roots? They extend above the soil surface and they’re really ugly.
Answer: Use either a tall groundcover such as liriope or ferns, or a vining type that would sprawl over the exposed roots. Choices would include English ivy and its many cultivars, Persian ivy, Algerian ivy (South Texas only), and the several vincas. Groundcovers won’t thrive unless you prepare their soil carefully. Use a mini-rototiller, and try to work it in between the major roots. You may be cutting many of the smaller roots, but the tree will recover. You can add organic matter into the soil, even though it means you’ll be raising the grade by a couple of inches. Organic matter doesn’t compact and drive out the available oxygen like a layer of new soil would do. If you’re going to install spray heads for the groundcover bed, run them into the bed from its perimeter (like spokes on a wheel), so you can parallel the major roots without having to cut them.