The first thing you have to understand about ground covers is that they aren’t always what they’re advertised to be.
Here’s what I mean.
They Don’t Replace Grass
This class of plants is touted as being a no-work replacement for grass. Well actually not.
The actual research on growing these plants versus turf indicates that turf grass is less work. The work in ground covers is in the hand weeding.
Sprays are not effective in stopping weed and grass invasions.
But don’t they stop weeds?
Not really. Grass will still invade the patch and unless it is promptly removed, it will out-compete the ground cover.
Having said that – a mature stand of well-established and maintained ground covers will “fight off” some grass that would normally invade a perennial garden. But you have to get it to that point first.
You mean they won’t effectively fight off grass? That’s true. Grass is more efficient a grower unless it’s in the shade and even then it can be a problem.
Ajuga ‘Blueberry Muffin’ lovely to look at but if it escapes into the lawn, you have a problem and it still needs hand-weeding
Walking on Them
I suppose you’re going to tell me that I can’t walk on a ground cover?
You can walk once or twice on some such as the lowest of creeping thyme but there is no ground cover that will sustain constant foot traffic.
Can I Use Ground Covers in my Dog Pen?
No. Dogs can kill grass and do worse damage to ground covers with constant exposure
I know that marketing programs suggest otherwise but the reality is that if you walk on a plant often enough, you’ll break the branches. Broken branches kill plants.
Some won’t take any foot traffic and others will take a little. You can also walk on them much easier in the early spring when they are still dormant (done all the time in the nursery industry) but once they start growing, the new active growth is pretty tender stuff and easily damaged.
What About Dry Shade?
Some of the shade-loving plants will be fine under light to medium shade if you water until they are well established.
Deep shade (under evergreens) and no water is a death sentence for most plants and even the ones that live will have trouble thriving. Your best bet for something like this is a heavy mulch to help the trees grow well.
But now you know.