Spillover plants

Sunday, 13 November 2011

Erigeron karvinskianus softens a brick wall

When we created our front garden, about 18 years ago, I had definite ideas of wanting a firm structure of brick terraces and paths, softened by plants tumbling over the hard edges wherever possible. This was what I had seen - and loved - in many English gardens during our trip there a few years previously. Whilst my gardening style has now moved on from trying to recreate an 'English' look and I now grow mainly semitropical plants, I never lost my penchant for cascading plants and have never wanted a totally streamlined garden where plants were entirely subjugated to the hard landscaping. Over the years, I have used many plants for this purpose. The seaside daisy (Erigeron karvinskianus) has always been in my garden, though I never remember planting it. Perhaps it came with compost from my old garden (I dug up most of the compost heap and brought it with me) and no sooner had our terrace gardens, paths and steps been built than the seaside daisy began to appear in cracks and crevices, providing just the hazy effect I wanted to mute the brashness of the new bricks.

Trailing Convolvulus sabatius at Red Cow Farm, Southern Highlands of NSW

To spill over the edges of my new sundrenched walls, I planted Verbena hybrids in many colours, providing long-lasting colour through summer and autumn. They are tough, drought-resistant plants and fit into a cottage garden scheme just as well as with a more tropical look. I replace them every few years with some young rooted pieces. Other good trailing plants for sunny places include catmint (Nepeta cultivars) with soft clouds of dainty lilac blooms; pretty Convolvulus sabatius with its pale or bright blue rounded flowers on long trailing stems during the warm months; a robust form of Dianthus (name unknown) with hot-pink flowers year-round; and the pendulous Russelia equisetiformis, which has long thin strands of wiry stems and bright red tubular flowers over an extended period; there is also a pretty, pale yellow form.

Nemesia hybrid intermingled with Euphorbia Diamond Frost in the garden of Carolyn Hughes in Sydney

For very dry spots, some of the low-growing perennial daisies with long stems will flow over walls: Arctotis has many colourful cultivars and revels in hot, sunny spots, as does the ice plant (Lampranthus spectabilis), which has shiny, multi-petalled blooms in a range of neon or pastel hues. Ivy geraniums are also wonderful hardy plants that will create a floral waterfall over walls - they will also climb on fences, so are very adaptable! Their glossy foliage looks good all the time. Another good groundcover for dry, sunny places that I have recently become aware in the gardens of some of my friends is a perennial form of Nemesia (possibly N. caerulea), in pinks, white and purple. It has a mass of tiny snapdragon-like blooms and it self-seeds in many gardens. I have recently been given some pieces of this plant so I am looking forward to seeing how it goes in my garden.

Saxifraga stolonifera on a low wall in the garden of Pamela and Harry Fowell in Sydney

In shady parts of the garden, the walls and paths were planted with a number of groundcover plants to drape over edges to give the desired effect: rhizomatous Begonia; several decorative Tradescantia species, in silver, purple or multicoloured hues; the creeping Saxifraga stolonifera, with silver-marked leaves and airy wands of tiny white blooms in late spring; and prostrate forms of Plectranthus such as Plectranthus 'Nico' and 'Nicoletta'. Most have attractive evergreen foliage so are decorative even when not in bloom.

Lampranthus spectabilis in the garden of Carolyn Hughes in Sydney

All of my spillover plants are equally as useful for groundcovers under other plants or along the edges of paths and garden beds at ground level to soften hard lines(note that husbands don't generally like this effect and may whippersnipper the sprawling stems off) and most are also eminently suited for hanging baskets. To stop these plants from becoming straggly, I cut most of them back at least once a year. The more tidy, compact sorts only need to have their flowering stems removed after blooming.