Diarmuid Gavin: Covering all bases
With some clever planting, you can eliminate weed growth with a sweeping ground cover
What's the big gardening job that comes to mind when people think about outdoor maintenance? For many, it's weeding - and we tend to hate it.
However, with a little bit of thought and planning, there is a way of planting in parts of your garden that can result in both an attractive and practical solution to garden maintenance: it's called ground cover.
This doesn't refer to a particular species of plants but the job that many plants can do if planted closely together as a group to form a continuous mat across the soil. Think of it as a magic carpet. The primary reason to do this is to suppress weed growth that would otherwise flourish in bare soil, so it's a low maintenance and environmentally-friendly way to banish weeds. Ground cover can also unify a planting scheme by providing a pleasing backdrop. It's a handy solution to tricky spaces like slopes that are hard to maintain and can be an alternative to lawns that are high maintenance.
We see this happening in nature. If you walk into woodlands at different times of the year and observe the planting, you can see what happens in nature can also be replicated in your plot. The forest floor may be carpeted in wild garlic or beautiful bluebells, and they're doing so well that nothing else can compete. Depending on your site and situation, you can choose plants that will form a blanket over soil which looks good for a lot of the year and leaves no room for other undesirable plants or weeds to invade.
So, how do you create a magic carpet in your plot?
First, you need to remove any existing weeds. Just as in cooking, start with a clean, uncluttered surface. Most plants will do better in enriched soil so add in some organic matter such as compost or well-rotted manure. You'll also need some mulch such as a fine bark to cover any bare soil that is left after planting - this will suppress weeds until your ground cover plants start to knit together and dominate.
Now select your species. You want plants that will spread but not so vigorously that they become a problem themselves. Ideally, choose plants that are evergreen, low maintenance, look good and flourish in your particular site and microclimate.
I use epimediums a good deal, once established they smother the possibility of any weeds, and I love them for their heart-shaped foliage and delicate flowers in spring. They're good for dry shade where they will form soft bushy mounds.
Pachysandra terminalis 'Green Carpet' (above) is an evergreen, low-rise 'shrubette'. Otherwise known as Japanese spurge, it has handsome glossy green-toothed leaves and white flowers in summer. Useful for partial or fully shaded areas, it will form a mat of green, just so long as the soil doesn't dry out.
Heucheras are well behaved ground covers - they don't invade but gently increase their girth. The vast range of foliage colours gives you plenty of choice, from deep purples through oranges to limey greens.
Hardy geraniums are one of the easiest perennials to grow and tolerate most soil. Some, for example, like Geranium 'macrorrhizum' (above), are semi-evergreen so will maintain coverage against weeds all year. Or try Geranium 'Ann Folkard' for summer ground cover - chartreuse green foliage topped with hundreds of deep magenta flowers will gently scramble through your borders.
Bergenia cordifolia is an excellent ground cover for dry shady places, one of the most difficult types of soils to plant. Known as Elephant's ears for the shape of its foliage, its thick green leaves are also tough like an elephant's hide. It's evergreen, with leaves developing a bronzy tint in winter, very hardy, and produces sturdy stems topped with clusters of small pink, ruby red or white flowers, depending on the cultivar.
Vinca or periwinkle (below) is a vigorous spreader that will save you hours of weeding. It is evergreen coverage 365 days a year with some lovely violet flowers in spring. It's adaptable to most soils, spreading over rocks, up banks and under trees. A word of warning though - only plant where you really want it to take over, so not in your herbaceous borders.
Even ivy works well if kept in check. There's some lovely variegated types such as Hedera 'Glacier' with grey-green lobed leaves subtly margined in white. It's fast-growing ivy and makes a great carpet. Or try Hedera Hibernian 'Rona' which has a broad, green leaf heavily speckled or marbled in cream-white whose colour deepens to cream as it matures.