Demure isn’t a word you’d associate with autumn perennials. Bold or beautiful is.
Without water, annuals and perennials hunker down and focus on sheer survival rather than putting on a spectacle. In dry times, choose plants that thrive on neglect. Heleniums and echinacea, for instance, tough it out when the going gets tough.
Ratibida columnifera is often included in wildflower seed mixes. Growing to 60cm tall, its upright stems are topped with a ring of drooping bronze petals around a pointy central cone. Its common name is Mexican hat because it resembles a Mexican sombrero.
GOLDENROD Solidago canadensis
is a herbaceous perennial with panicles of rich yellow flowers on stiff, upright stems. It's winter hardy, tolerant of heat and humidity, and excellent for cutting. It mixes well with the steely-purple globe thistle, Echinops ritro.
Coreopsis – both the quick-to-flower annuals and hardy perennials – deserve to be more widely grown. They grow everywhere, needing regular watering only at the start to establish. These daisies come in yellow, cream, yellowbronze and burnt sienna.
Perennial purple coneflowers (Echinacea purpurea) are workhorses in the summer and autumn garden. They produce an abundance of purple-pink blooms which consist of a central cone surrounded by a skirt of petals that hang downwards. As the petals fade, pull them off and use the ornamental cone in arrangements. This hardy perennial is easy to grow, flowering the second year from seed. It's heat- and drought-tolerant, with very few pest problems.
For bright colour and long flowering, plant a swathe of helenium. These are versatile plants, thriving just as well in windy, mild-climate gardens near the sea as in inland gardens. Any reasonable soil suits them fine, and they rapidly grow into generous clumps. 'Moerheim Beauty' is usually the helenium variety of choice for its long-blooming season and unique colour, though 'Walstrand', 'Sahin's Early Flowerer', 'Butterpat' and 'Lord of Flanders' are equally enticing.
When carefully selected, waves of colourful blooms can be enjoyed year after year in the late–season garden.
While the purple coneflower is the most popular, breeders have managed to come up with more upright and even double cultivars, in varying shades, including white, peach, tomato red and yellow. Seeds for 'White Swan' are readily available. This plant's blooms, which are 10-12cm in diameter, start out lime-green to cream, then mature to pure white. Plant 'White Swan' with Geranium 'Rozanne', which flowers almost continuously from summer through autumn, and the clump-forming spiky Eryngium planum, or sea holly.