The Dianthus family contains more than 300 flowering plants, including the carnation and Sweet William. The flowers are known for their masses of colorful blooms that occur in the spring and summer months. Dianthus flowers are grown both commercially and in many home gardens to add color to the landscape. Although they die back in the late summer to early fall, the barbatus, chinensis, plumarius, deltoides and superbus varieties of Dianthus are all perennials that will re-bloom the following spring.      

      
Grow perennial dianthus in full sun, in moist, well-drained soil. Some perennial dianthus self seed. If you don't like the extra plants, weed them out in the spring when they are still small. Enrich the soil with compost every fall to prevent the center of the plant from dying out. Perennial dianthus are divided in autumn, too.

Read more: How to Divide Perennial Dianthus | eHow.com http://www.ehow.com/how_8190133_divide-perennial-dianthus.html#ixzz1rVKx0UCq
Read more: How to Grow Dianthus Perennial Flowers | eHow.com http://www.ehow.com/how_7524378_grow-dianthus-perennial-flowers.html#ixzz1rVIm52qQ