Sunday, 31 January 2016

Rudbeckia laciniata

In my quest for easy-to-grow plants for the Sydney climate, I have found that a number of beautiful flowers from the North American prairies are among those which thrive in my garden, bringing welcome colour in late summer. Some of these plants gained prominence in the 1990s as components of the naturalistic 'grassy' borders of designers such as Piet Oudolf, and whilst they are indeed stunning combined with ornamental grasses such as Miscanthus and Pennisetum, they are also fabulous companions for my semi-tropical style plants, such as Dahlia, Canna and Salvia.

Generally, they are herbaceous perennial plants, dying back to a basal clump of leaves in winter then building to a substantial size in the warmer months. They have tough roots and seem to cope well with the humidity of Sydney summers, unlike many European herbaceous plants. They like to have decent soil and some water during their growing season but they survive periods of drought quite well. Most benefit from being divided up every few years.

Echinacea purpurea

Many come from the Asteraceae family of plants, with their daisy-like form. Bold-flowered examples include the lovely purple coneflower (Echinacea purpurea); a number of forms of Rudbeckia (also known as coneflowers) with their wonderful golden blooms; Gaillardia hybrids (blanket flower); and perennial sunflowers (Helianthus).

Eupatorium purpureum at Belrose Nursery

Daintier daisy types are found on the many sorts of perennial Aster species and the less-common Boltonia asteroides. Joe Pye weed - (Eupatorium purpureum) - is also from the Asteraceae family, though it looks nothing like its relatives, having clouds of tiny fluffy mauve blooms on tall stems. (It has a close cousin from Mexico called Eupatorium megalophyllum (ht 1.5m), which has big fluffy heads of lilac purple flowers in early spring, held above wide, velvet leaves.)

Physostegia virginiana

Other prairie-dwellers have spires of flowers, such as the obedient plant (Physostegia virginiana) with its purple or white blooms which can be moved around on the stems; Veronicastrum virginicum with pretty white or pale pink tapered flower spikes; and perennial Lobelia: Lobelia siphilitica has blue or white blooms, whilst Lobelia cardinalis has dark red flowers atop chocolate-coloured foliage. Tough groundcovers such as Evolvulus pilosus with its pretty blue flowers, and pink or white evening primrose (Oenothera speciosa - not to be planted where you mind if it takes over) are other examples of prairie plants which do well in Sydney gardens.