Ground Covers…The Good, The Bad, The Ugly
I grew up in the ground cover business. In addition to our nursery, Moretti’s to our north (now Briar Rose Nursery) and Beardslee Nursery just beyond, specialized in traditional ground covers. Out in Madison, Logan Monroe at Kingwood Nursery did the same (Kingwood was sold to Warner Nursery and is currently owned by Phelps Ohio Nursery). Some people believe that ground covers are in conflict with local ecologies and invasive plant concerns. Actually, there’s more to the story.
We always noticed that euonymus fortunei coloratus, Wintercreeper, sprouted flowers and seeds when permitted to grow upwards. This anomaly was a source of interest but not concern, until folks in Southwest Ohio observed it taking over natural areas. Our OIPC Assessment Team, including two members selected by the nursery industry, scored this plant at 45, the bottom threshold of ‘invasive’. I suspect that a reexamination in future years will only move this plant higher on the scale. There are no ‘invasive plant regulations’ in Ohio yet, the Ohio Department of Agriculture is currently drafting rules, so we still grow and sell this plant. However, beds of coloratus always seem prone to scale infestations over time. They look unruly if not trimmed twice a year. It’s never been one of my favorites. The demand has been decreasing steadily in recent years. We will stop raising it soon and shed no tears at that occasion. (Personally, I believe Cotoneaster dammeri ‘Royal Beauty’ is a great substitute.)
Hedera helix is another story. Growing up, we made wooden ‘flats’ by cutting down grape lugs on a table saw, nailing in sides and bottoms, and adding cleats. We prepared cuttings of English Ivy, Baltic, Thorndale, Wilson, 238th Street, Yalta, Rochester and many more, and rooted them on the ground under mist. By the time white roots crept out the bottom of the flat and clean shiny new growth covered the top, they usually contained lots of spotted leaves inside the dense foliage which we removed by hand. Over the years, we learned to select varieties less susceptible to bacterial leaf spot, grow them on raised benches and cultivate clean cutting stock from hanging baskets. Leaf spot is not much of a problem for us any more and we rarely spray for it.
Anyone who ever ripped out a bed of ivy will swear it is invasive. They will swear a lot. But we decided with our Ohio Assessment Protocol, unlike other states, that ‘difficulty of control’ was not a measure of actual ‘invasiveness’, a defined term. Ivy does not ‘jump spatial gaps’ in Ohio. It is not invading ‘natural areas’ like it does in the Pacific Northwest. As a result, it is not on our list of ‘invasive plants’ and I don’t think it will end up there. It remains a very effective ground cover for cultivated areas.
Likewise, Pachysandra terminalis is a ‘non-invasive’ vigorous spreader in Ohio. Where we find it in the woods it was likely planted there in connection with a homestead. It runs but doesn’t jump.
These were the big three ground covers when I was growing up. Along the way we added many other great performers, vigorous and durable plants that cover quickly and crowd out the weeds, …lamium, waldsteinia, liriope, gallium, thyme, vinca. Now we’re adding and featuring ground covers native to Ohio or nearby areas…sedum ternatum, phlox subulata and opuntia humifusa. In 2017 we will offer pachysandra procumbens, waldsteinia fragarioides, anemone canadensis and more. Meantime, we have voluntarily deleted bad-actors from our list like Lonicera ‘halliana’, Lythrum salicaria, Celastrus orbiculatus.
Are there ‘ugly’ ground covers out there in the landscape. Yes! Who likes concrete and asphalt when we can have living tapestries! Am I the only one who doesn’t like painted mulch?
We assisted in the creation of the OIPC Assessment Team and support their activities, but we maintain there will always be an appropriate and functional place for non-invasive ground covers in Ohio landscapes.