Posted: 24/05/2012 at 13:30
If you want to cut flowers early in the summer and then enjoy more blooms later, you'd be better off growing perennials. They have the strength in their rootstock, gained over the years, to cope with being cut back a lot. You'll hear the phrase 'Chelsea chop', which involves cutting back flowers after their first flowering in May for a second display in late summer. As Kate1123 says, it's a good idea to read the seed packets for timing, but weather conditions will always make a difference.