Plant of the month Dahlia Autumn Lustre
Everyone knows of a good dahlia but as far as I’m concerned they don’t get much better that Autumn Lustre, a bright Orange Waterlilly Dahlia that keeps on flowering from midsummer until the frosts knock it back down to the ground. Autumn Lustre grows to about 1.5m in height with flowers of about 12cm in width. It has also has great dark, divided foliage that help to offset that vibrant orange flower. Once established this dahlia can bulk up to provide an impressive display in any style of garden.
Very little is known about the dahlia before the time of the Aztecs. It is believed that the Aztecs used parts of the dahlia for food and medicine. The mountain regions of Mexico and Guatemala are the birthplace of today’s dahlias and they have continued to be grown there.
Seed and plant parts of dahlias were sent to Europe around the 1800s. As Hybridization work quickly started, the first fully double forms began to make their appearance, as did many new colour combinations. It was around this time that the scarlet Dahlia coccinea was crossed with a mauve-flowered species, possibly D. pinnata, which ultimately resulted in the first modern dahlia hybrid. The new hybrid was easy to grow and hybridize so they quickly became very popular in European and American gardens.
Dahlias are an excellent plant, great for bold planting schemes. They are quick growing and provide an impressive display of colour late in the season. They prefer being planted in full sun with fertile, well drained soil. They are a little tender so need some protection from the frosts. This is why traditionally the tubers were dug up and stored inside for the winter. However, I have found that with a good mulch that they are quite reliable about showing their heads again, even after the harshest of winters. The main issue you may find is the winter wet, they don’t like soggy feet, so if you have a heaver soil that gets waterlogged in the winter, it may be best to bring them in to the warm of the shed or at least include some good drainage in the form of grit / shingle under the tubers when you plant them. Slugs and snails also have a good appetite for fresh dahlia stems so some form of protection when they first start to shoot is almost essential.
All dahlias can be a little wayward when it comes to their growth, the taller varieties especially. They all benefit from some staking to keep them growing upwards and not flopping due to the weight of water from a recent shower. This needs to be done early in the season allowing the dahlia to grow through the support system in place. Staking after a flop ensures a very funny looking arrangement in the border for at least a week or two until new growth comes through to mask what’s underneath,
Dahlia Autumn Lustre, I think, is best combined in a mixed planting scheme that is focussed on late summer. Try planting in front of a clump of Miscanthus where the foliage of the dahlia contrasts well with the spiky nature of the grass. Add some Echinacea purpurea, Aster frikartii monch and Salvia Amistad into the mix too and you have created a rich and vibrant scheme that will keep flowering until the frosts arrive in November. What more could you want!?!