Guide to growing garden plants - Dianthus (Sweet William)
Dianthus can come in many forms; annuals and perennials include the carnations, whereas the biennials include Sweet William. This page is dedicated to the biennials, Go here for information on Carnations and Pinks.
Sweet williams and other Dianthus plants tend to have a bushy nature and grow from 30 to 75cm in height.
Flowers may be red, violet white or pink when one coloured; however Dianthus can often have double and triple coloured flowers, that are singular or double petalled; often with serrated edges.
How to grow Sweet William (Dianthus)
If sowing sweet William seeds outdoors then they should be sown at a depth of about 7mm into a sunny part of the garden (from mid spring to July). They should be grown with a spacing of 20 to 25cm apart in a deep and rich slightly acidic to neutral soil (pH 6 to 7). Sweet William is a biennial so will flower in the second year. if you prefer to start seedlings of Sweet Williams off indoors then they should be started about 8 weeks before they are transplanted into the garden in autumn (or late spring). Germination at a temperature of about 20 degrees Centigrade takes from one to two weeks.
Caring for Dianthus
If you require more Dianthus plants then cuttings can be took from the root.