Aster novi-belgii

While its root spread can be contained with the blade of a spade, it is the aster's susceptibility to mildew that gardeners find most threatening, especially among the aster novi-belgii group from North America, one of our most widely grown varieties.

* Michaelmas daisy (Aster novi-belgii & A.novae-angliae)

It was begun by Edward Ballard, a chemist and hobby gardener who became a nurseryman by default, as a result of his success in raising exquisite new varieties of Aster novi-belgii, also known as New York asters.

But so many superior varieties are now available from the North American Aster novi-belgii, the plant is indispensable in the autumn garden, so long as specimens are divided at least every fourth spring when all but the young outer shoots should be discarded.

Top sellers include autumn-flowering colchicums, Yoder mums, Michaelmas daisies (Aster novi-belgii) and 'Miracle' cyclamen as well as the day-glo dyed bud heathers.

Alternatively, try the pink and purple shades of a variety of Aster novi-belgii, which is compact, bushy and suitable for container planting.

TO create a seamless late-flowering border, look to nature for inspiration and plant feather reed grass, Calamagrostis Karl Foerster with the Michaelmas daisies Aster novi-belgii Coombe Rosemary and Ada Ballard and agapanthus in interlocking bold drifts.

The true Michaelmas daisy (Aster novi-belgii) is most susceptible to a whole range of fungal diseases, but there are some varieties, like Royal Velvet, which are resistant.