How to prune perennials
For well-shaped plants with an abundance of beautiful blooms, use simple methods to control growth and prolong the flowering period of your perennials.
Pruning and thinning perennials improves flowering and keeps plants blooming longer. The result is more and sometimes larger blooms. The following tecnhiques encourage plants that are healthy and bushy to produce an abundance of buds early in the season. Later maintenance removes spent flowers to encourage repeat blooming and keeps plants from becoming ragged and overgrown.
Pruning early in the growing season, when the plant has just leafed out, improves the shape and removes spindly, weak growth. During the growing season, pruning removes spent flowers, dead growth and leggy stems. Late season pruning of perennials removes declining growth such as dying stems and prepares the plants for winter.
Pinch back outer tips
The first action to promoting healthy, strong perennials is to pinch back the outer tips of upward-growing stems, or weak, spindly growth to encourage bushy side growth. Pinch back early in spring to help shape the plants and to allow buds maximum time to form.
Cut leggy growth
To encourage lots of strong flowering stems, use your clean, sharp secateurs to prune back young shoots on plants that tend to sprawl or become leggy. Cut these stems at ground level.
Remove spent flowers
Continue to regularly remove spent flowers throughout the growing season so plants form new buds and not produce seeds. Prune the finished flower stalks back at ground level, unless new buds appear as side shoots. If so, cut these stems a few inches (centimeters) below the finished flower to be sure you get the entire seedpod.
Cut back after first flowering
After the main flush of flowers, prune back the plants overall growth by as much as one third to encourage a second flowering cycle. This also keeps the plants looking compact and neat while helping to rejuvenate older perennials. Take off any dead shoots at ground level and cut back other just above new, green growth.
Fertilize and water
Your perennials need consistent care, including regular fertilizing and watering after you prune. Fertilizing and watering provide plants with the strength to develop fresh foliage and new flowers. Applications of a liquid fertilizer at regular intervals will ensure a continual supply of the plants much needed nutrients.
Support flower stalks
Pruning by pinching or cutting back plus a boost of fertilizer will result in an abundance of new flower stalks, and some of these will need support. Use bamboo stakes or plastic supports to stake the flower stalks before they begin to slump over. This will allow for maximum flower production.