Better Ground Covers for Shade to Replace Problematic Plants

 Great ground covers 

Try these top-performing options for weed control that won't spread out of control "Landscape" technically refers to the basic layering of the four forest stages: ground cover, shrub, understory, and canopy. But in horticulture, ground covers are generally considered low-growing or trailing plants that are used to cover large areas. Since the primary goal of a landscape is to cover the ground solidly and quickly, plants with these characteristics are ideal for that purpose. It is a boon in appropriate use. Place the same plants in perennial borders and they will become a barrier.

Some common ground covers spread so effectively that they can become aggressive and grow out of control. As I discuss alternatives to those rugged traditional ground covers listed here as problem plants, keep in mind that each may still have merit in the right setting. At the right site, these problem plants may have some value. However, don't use anything listed as invasive in your area. There is no justification for using them. In my gardening experience, I've focused on one mantra that dictates every planting choice we make: "Right plant, right place." Keep that in mind when deciding which landscape is right for your garden.

Problem Plant: Lily of the Valley

The plant prefers dry, shady conditions where it doesn't mass tightly, and there are gardeners who love its richly scented flowers. Recent variant introductions have renewed its appeal. However, sunlight and rich garden soil greatly increase the density and spread rate of this plant. It can quickly go from a cute spreader to an aggressive rogue.

Alternative plant: Golden Ragwort

This eastern North American native completely covers the ground in which it is planted and spreads rapidly by both rhizome and seed. However, I find it much thinner and easier to control than Lily of the Valley. I've planted it under several mature American lindens (Tilia americana, zones 2-8), which rob the surrounding soil of moisture. Golden ragwort thrives in this setting where most plants would be abandoned. The cheerful yellow, daisy-like, long-lasting flowers are most welcome in early spring; They provide some of the first bright colors that herald the end of winter doldrums.

Problem plant: Bishop's weed

The best tip I've heard for growing this plant is "it's in concrete". If you have bishop's weed growing on your property, you understand why this is advised. I don't see green-leaved species commonly available, but the attractive variegated foliage of the variety 'Variegata' (pictured) has made this plant very popular as a landscape. Generally, variation weakens a plant's aggressive behavior. But in this case, the cultivar is just as harmful as its parent.

Alternative plant: ‘Halcyon’ hosta

Since bishop's weed is grown for its leaves and not its flowers, I recommend Foliage Queen as an alternative. Hosta's aren't usually considered ground covers, but you can't beat their durability in part to full shade. There is no better weed control for large spaces than packing Hosta's together. They provide dense shade where weed seeds cannot germinate. If you are using Hosta's as a ground cover, it is best to choose an inexpensive and readily available variety. 'Halcyon' is an old, tried-and-true hybrid. The glossy-blue, dense foliage resembles seersucker fabric and is a soft, neutral shade of green that works with many colors.

Problem plant: Ajuga

Don't get me wrong - ajuka has its uses, and I grow many varieties myself. But one of the primary problems with it is that it can spread across grasslands and become difficult to eradicate. As a border plant, it spreads very quickly, requiring annual division and control. In areas with winter snow, it is highly susceptible to gray snow mold; I have seen enormous patches destroyed in some springs.

Alternative plant: Meehan's mint

Meehan's mint is similar to ajuka in its growth habit, with rich glossy green foliage that stays in the heat of summer as long as the soil doesn't dry out. It blooms in mid to late spring with profuse hooded lavender-blue flowers. Native to eastern North America, it tolerates deeper shade than most plants I know. I grow it as a walkway, in sun and shade with equal success.

Tip: Mix it up

Ground covers are almost always planted in mass groups of the same plants. I encourage you to look at these plantings with some eyes for design, just as you would in your perennial garden beds. Monocultures of any plant have many problems, including disease susceptibility and insect damage; A single problem that infects and kills a plant can destroy an entire stand. Adding other plants increases visual interest and biodiversity. Mix other perennials with ground covers that aren't too dense and play well with others. If a landscape is too robust and invasive to plant with other perennials, use sturdy shrubs instead.

Problem plant: Blue sedge

I've used this beautiful, soft-textured sedge before. It has attractive glossy-blue foliage. While it tolerates dry shade well, there is recent evidence that this European native is making inroads into North America. It is found outside of cultivation in the forests of the Mid-Atlantic, Northeast and three Canadian provinces. This information is so new that blueberry cultivars are still marketed and sold without notice.

Alternative plant: Pennsylvania sedge

Even as a teenager, I admired the soft, flowing look of what I thought was a neat, beautifully curved grass across the woodlands of upstate New York. Pennsylvania sedge is shade and drought tolerant, and I use it as a soft textured carpet around other perennials in my garden; It works well in woodland planting schemes. This eastern North American native is an excellent textural foil for thick foliage plants. Bristle-leaf sedge provides similar service in sunny locations.

Problem plant: Japanese pachysandra

This plant has long been the queen of ground covers for those with Japanese-inspired gardens and deep shady areas. However, any amount of sun turns the glossy green leaves a sickly yellow. It grows with thick matted roots, so that it does not have a chance to combine with other plants, it is very effective in propagation. Volunteers were once asked to remove overplantings of pachychandra, which could only be achieved by cutting the heavy and impenetrable roots 8 to 10 inches long.

Replacement plant: Allegheny spurge

Unlike the aforementioned Japanese species, the foliage of this native pachysandra has a light glossy-blue matte finish. Once established, it is very drought and shade tolerant. There are also some pretty versatile cultivars. Allegheny spurge is native to the southeastern United States and does best in acidic soils, but I have found that it is more forgiving of alkaline conditions than many acid-loving plants. It is not commonly sold in garden centers in many parts of the country, so mail-order sources may be the only option for some gardeners.