Before pruning, it's important to know the pruning needs of each specific variety of perennial plant in your garden. Below are some tips for pruning and deadheading many types of perennial plants. Pruning refers to the cutting back of perennials to control size, to shape or to encourage a new flush of growth and, in many cases, a new flush of flowers.
Pruning Instructions
Deadheading
Deadheading (the removal of spent flowers) is a simple task which takes a few minutes however adds days and sometimes weeks to your flowering display.
If you've never dead-headed before here's how go about it:
First, keep a watchful eye on your flowering plants, paying close attention to blooms that are past their best. Once a flower has started to fade remove it from the plant with a quick snip from your pruners. Alternatively, if stems are thin or soft, nip the flower stem off with your thumb and forefinger. When doing this try to remove just the spent flower and its stem, leaving any new flower buds beneath intact.
Cutting Back
Many perennial plants can benefit from a shearing or cut back during the season. Lantana, verbena, coreopsis and many other summer-flowering perennials respond well to a mid-summer shearing, and will bloom heavier after doing so. Garden phlox and other perennials will produce a second flush of flowers when cut halfway back and fertilized after blooming.
At any time during the warm season it is okay to cut back dead or ugly foliage.
Winterizing
When winter has arrived, and your perennials have either died back or stopped growing, you can remove all dead foliage. Then apply an inch or two of compost or mulch around plants. Leaves work great for mulch as well.
Other Helpful Tips
- DO NOT prune lantana back during the Fall. Doing so insures death of the plant. The time to hard prune lantana is in mid to late Spring when new growth begins to emerge. At this time, prune back all dead stems to a point just above where new growth is emerging.
- If you clean dead flower stems from your daylilies you might get a repeat bloom.
- Wait to cut back butterfly bush (Buddleia) until new growth begins to emerge in spring. AT that time you can remove all dead stems or cut plants back by 50% or more their height. Deadhead flowers throughout the summer to encourage heavier flowering.
- DO NOT kill the ants that visit your peonies. The ants eat the sticky residue that forms on peony buds allowing the flower to open.
Let me know if you have any other perennial pruning tips and I'll add them to this list!