Covering the ground

Sunday, 25 September 2016

A very weedy spot in my garden!

Weeds, weeds, weeds! Was there ever a spring with so many weeds? The recent rains have seen them proliferate madly. My garden is awash with them, and no sooner do I pull them out than more appear. They say that Nature abhors a vacuum - and it seems she hates a bare patch of soil too. Whilst I have many bales of cane mulch ready to spread, this task hasn't been done yet as I have been spreading all my bags of cow manure first - a spring ritual to keep my soil in good health.

Some plants will also receive a blanket of homemade compost - mainly my Hydrangea and Camellia shrubs, and plants growing in beds where the soil is not as good as elsewhere in the garden. However, spreading the cane mulch will be a vital step in my fight against the weeds. This form of mulch lasts a long time, helps retain moisture in the soil, and stops many weeds from growing. Eventually it breaks down and adds to the organic content of the soil. I spread it more lightly in areas where I hope for self-seedlings to appear, or wait till these come through before applying the mulch.

Violets make a robust groundcover in sun or part-shade, with dainty flowers in late winter and early spring

In some areas of my garden, however, the planting is so dense that there is no room to put mulch down. These borders have an underplanting of low groundcovers that run between shrubs and clump-forming perennials, and weeds are far fewer in these areas. I love the look of the tapestry of such groundcover plants and want to grow more of these in my garden to help with my weed problems! These plants are especially useful in slightly 'wild', out-of-the way spots in the garden where you'd like to have a swathe of greenery without having to constantly weed, but where grass won't grow and a vast blanket of cane mulch could look rather dull.

When planting out groundcovers, it is important to start out with a weed-free soil - as far as humanly possible, that is! Enrich the soil with compost and give your groundcover a good start in life by watering it in well with a seaweed extract solution. Keep it well watered until it is established. It is useful to provide a surface mulch of compost to cover the surrounding soil whilst the groundcover is establishing, in order to avoid more weeds emerging in the meantime. This sort of mulch will break down by the time the groundcover gets going. By their very nature, most groundcovers are fairly vigorous plants and will make a decent-sized carpet. More and more in my garden I want bigger groups of a smaller variety of plants, to give more impact than the dizzying melange of many different individual specimens that was once my style.

Lamium maculatum White Nancy

Generally speaking, I choose groundcovers that have interesting foliage and, if possible, the added bonus of flowers. Some of my favourites are coming into bloom now. Lamium maculatum is a beautiful groundcover for shaded spots, as long as there is some moisture in the soil. It has stunning leaves marked with silver - in some cultivars there is only a tiny margin of green on the foliage. Lamium has pink, white or purple hooded flowers in spring, when the foliage seems truly at its best. It makes a wide mat when it is happy. It is best to avoid yellow-flowered Lamium galeobdolon 'Variegatum', which can be quite invasive, unless it is for a truly wild part of the garden!

Saxifraga stolonifera

Another good groundcover for shade is Saxifraga stolonifera, which has silvery-veined rounded leaves and a froth of tiny white blooms in mid-spring. It spreads stealthily via its stolens, but is easily pulled away from areas where you don't want it. I enjoy growing this in and around hybrid hellebores. The species geranium Geranium macrorrhizum is also a shade-dweller, growing into a wide mat of rounded green foliage with a felt-like texture. In spring and early summer, gorgeous flowers of pink, purple or white float above the leaves like dainty butterflies. It is one of the best species geraniums for the Sydney climate.

Rhizomatous Begonia Silver Jewel

Rhizomatous Begonia include some of my favourite groundcovers for shade. There are so many cultivars of these amiable plants, with leaf colours ranging from silver to near black, and a mindboggling diversity of patterns. All the rhizomatous Begonia bloom in spring, with clouds of pink or white rounded flowers. Growing a few different varieties together as a carpet below shrubs can make an effective, low-maintenance garden area. In the Begonia Gardens at the Royal Botanic Garden in Sydney, there is a wonderful demonstration of how these plants can be used as a groundcover around taller plants.

Pretty foliage of Campanula poscharskyana

For areas with a bit more sun in the garden, Campanula poscharskyana is a good choice of groundcover, with ruffled, heart-shaped leaves and blue, white or (rarely) pale pink bell-shaped flowers in October and November. Sweet violets (Viola odorata) grown en masse can make an excellent weed-suppressing rug. It is fun to grow pink-, white- and purple-flowered forms together. Violets can stand quite sunny positions. Herbs such as thyme and golden oregano can be useful groundcovers in hot, dry spots in the garden, as can Gazania, Arctotis and Convolvulus sabatius.

Sedum mexicanum Gold Mound with annual Lobelia

Sedum mexicanum 'Gold Mound' is one of my top favourite groundcovers. Its multitude of tiny sprigs of fleshy gold leaves can cover a good amount of soil over time, and at this time of year, it really glows! Grown in shade, where it does just as well, the foliage takes on a limey hue. I love to have it growing around orange Clivia for a real colour pop. I like it with yellow flowers such as Bulbine frutescens (in bloom now) and I also adore it with rich blue flowers, such as the annual Lobelia, illustrated above. The Sedum will have bright yellow blooms itself in mid-spring.

Massed bromeliads can make a great groundcover, as seen in the garden of Sandra Wilson in Sydney

All of these I have mentioned are ground-hugging specimens, but taller, vigorous clump-forming or spreading plants such as Clivia, bromeliads, Japanese windflowers, Plectranthus 'Nico', Pilea cadierei, star jasmine (Trachelospermum jasminoides) and Liriope - and even prostrate-growing shrubs - can also play a role in covering the ground, and helping to avoid the dreaded task of weeding.