The month of July is a pivotal month for pruning flowering perennials from the past and for the future. Early to mid-season blooming perennials such as peonies, coreopsis, early daisies (there are so many varieties of daisies we will simply refer to them as early or late blooming varieties), daylilies, bellflower and balloon flower.
Another flowering perennial that I thought was disappearing from everyone’s gardens but needs to be pruned right now is the Yucca Plant. It seemed that the Yucca was not included in landscape plans these days but if you “hang out” in older neighborhoods or visit parks and zoos, they are plentiful. I am not sure why no one gets out there and prunes them once the flowers have faded. They just get uglier with time and the fact that they now start to form seed pods sucks the energy right out of the plant for up-coming years.
When it comes to perennials, removing the spent flowers and pods as soon as possible is crucial for the strength of the remaining plant. There is simply no reason to keep the ugly stems and seed pods on the plants. However, there are a few perennials that can reproduce and make more plants from the seed that develop and drop off the stems. Columbine, Bachelor’s Buttons, Jacob’s Ladder, Sweet William and Yarrow are examples of self-seeding perennials. If multiplying your perennials is what you want, then great but if you do not want them to spread, then prune just as soon as flowering is over. Most perennials multiply underground and simply get larger each year and need to be dug up then divided.
After pruning keep your perennials watered and add slow-release fertilizers such as Garden Fertilizer or Bone Meal. It is important to “grow” your plants for the rest of the summer to make healthy, strong plants for next year.
Please note that we have only addressed spring and early summer flowering perennials and not the many fall blooming varieties such as hydrangeas and garden mums and asters. These plants should be cut back in April/May/June so that these late bloomers have a chance to grow through the summer months in order to bloom on time. If you do not cut them back at the proper time, your plants may grow too tall, too short, or worse yet, no blooms. Timing is everything!