Put a note on your calender next May or early June that reads PLANT DAHLIAS. Or Dahlias, zinnias and Verbena bonariensis, for that matter. With this mix of plants you’ll be able to pick technicolor bouquets in the late summer and fall. Since I live in a warm zone 6 I can also add a wealth of Hydrangeas to the mix of cut flowers. Along with harvesting dinner from the vegetable garden, cutting bouquets from your landscape is one of the most satisfying things on earth.