Plant of the month October

Late summer rays trigger a burst of colour

As summer fades into autumn there are some fantastic late flowering plants to look out for that add a last injection of colour at the end of the season. Although many perennials reach their peak earlier in the summer it is worth adding one or two late flowering perennials to your borders to give them a fantastic lift.

Plants for autumn flowers

Good flowering plants to look out for include asters, chrysanthemums and sedums. Our plant of the month, Leucanthemella serotina, is a relative of the aster with the same flower structure and shape, it is also a tall perennial that reaches 5-6ft when it is growing in good soil.
Leucanthemella serotinaLeucanthemella is clump forming, and will spread slowing using white, creeping rhizomes. It can be utilised towards the back of the border where it will give good height, although it will need staking to keep upright throughout the summer. To reduce the need to stake, the tips of the stems can be pinched out in spring to encourage it to branch out.
Although this perennial can look fairly plain during summer it reaches its peak in autumn when its impressively late flowers open to reveal white petals with greenish-yellow centres that are about 7cm across. Leucanthemella grows at its best in moisture retentive, well-drained soil in an open sunny position and it is generally easy to maintain and trouble free, although it does benefit from being divided every five years or so. At RHS Garden Hyde Hall you can find it growing in the Herbaceous Border in the Hilltop Garden where it features in the white, green and lemon planting combination.
We like to utilise this plant as it gives us good height towards the back of the deep border and it associates well with plants such as Anemone x hybrida ‘Honorine Jobert’ with its clear white flowers as well as Symphyotrichum novae-angliae ‘Herbstschnee’, a tall cultivar with small white flowers. For interest earlier in the season try Cephalaria gigantea with its scabious-like lemon flowers or in front of it try Anthemis tinctoria ‘EC Buxton’ with its soft yellow blooms.

Autumn planting ideas

For seasonal interest we may interplant between the perennials with annuals such as Cleome hassleriana ‘Helen Campbell’ which has white spidery flowers or Cosmos bipinnatus ‘Purity’ with its fern-like foliage and white flowers carried on tall, slender stems. We also utilise dahlias through the border such as ‘Lady Linda’ with its large, lemon-yellow flowers to add colour until the first frosts arrive.

More information

Planning your garden
Autumn perennials


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