Aster 'Violet Queen'
For vibrant colour from late summer through the autumn, asters are hard to beat. With vibrant colours of purples, reds, pink and whites they are great for the border and some varieties can also be grown in pots.
As some of the summer colour from lavenders and salvias starts to fade, the purple asters can extend the colour right through to the first frosts.
There are new varieties that have been bred for their more compact habit reaching around 30 to 45cm (1' to 1½') whilst taller varieties grow to about double this size. They all grow best in a fertile position in full sun and need to be kept moist but not waterlogged. Over the winter they will die back to ground level to re-emerge the following spring.
Asters can suffer from mildew, ensuring that they do not dry out will greatly decrease the chance of this and also spraying with rose clear at the first signs.
Consider growing asters in a mixed planted container for the first year together with foliage colour from heucheras and conifers before moving it into the mixed border for subsequent years.