Q: In floral arrangements I often see a cut flower that looks like a clump of
moss on a long stem. Do you have any idea what it could be? 

A: Cool looking isn’t it!? I have no doubt you are seeing ‘Green Ball’ or
‘Green Trick’ dianthus. The Latin name, Dianthus barbatus, tells us that it is
close kin to carnations, sweet William, and garden pinks. Most dianthus are
biennial plants. You plant the seed in late spring, a green rosette of leaves
appear in summer and flowers emerge the following spring. Dianthus plants
you buy at a nursery were propagated in a greenhouse the previous year, so
they are ready to flower after you plant them.