Hardy Geraniums (also known as Cranesbill) are a total staple in the garden, especially if you need a reliable groundcover for those tricky shady spots. Most varieties are super vigorous growers, but they can sometimes get a little wild, sending out long runners and trying to climb over everything in sight. To keep them looking tidy and lush, a little haircut every now and then is a must.
When should you prune your Hardy Geraniums?
Timing really depends on which variety you have in your garden. If you’ve got a “repeat bloomer,” you’ll want to do what we call a “rejuvenation cut” right after the first flush of flowers starts to fade. This encourages the plant to push out a second round of blooms. Here are some common varieties that love a mid-season trim:
- Clarke’s Geranium (blooms June or August)
- Pink Geranium (blooms April or June)
- Showy Geranium (blooms May/June)
- Oxford Geranium (blooms June or August)
- Mourning Widow (blooms June/July)
- Meadow Cranesbill (blooms July to August)
- Caucasian Cranesbill (blooms June/July)
Before you grab your shears, double-check your specific variety’s blooming schedule. If you prune at the wrong time, you might accidentally snip off the flower buds you’ve been waiting for!
The Rejuvenation Cut
For this method, you’ll want to cut back the faded, dry flower stalks all the way to the ground. Try to leave the healthy green leaves alone so the plant can keep photosynthesizing and bounce back quickly. After pruning, give your geranium a little snack with some liquid all-purpose fertilizer and keep the soil nice and moist. This “wakes up” the plant and triggers that second bloom. In about six to eight weeks, you’ll see fresh new growth—this is the plant “remonting.” This trick works best for spring bloomers that have enough time to flower again in the fall. Late-season bloomers usually won’t flower a second time, so they don’t need this extra step.
Pruning in Late Fall or Early Spring
Many hardy geraniums can get over 20 inches tall and start to look a bit floppy or “split” in the middle. To keep them looking compact and bushy, a structural prune is necessary. You can cut these varieties back either in late fall or just before the new growth starts in early spring:
- Cambridge Geranium (best pruned in spring)
- Gray Cranesbill (best pruned in spring)
- Heart-leaf Geranium (best pruned in spring)
- Showy Geranium (prune in late fall or winter)
- Knotty Crane’s-bill (prune in fall)
- Bloody Cranesbill (prune in fall)
- Siberian Cranesbill (prune in late fall)
When you do a late fall pruning, you can cut all the stems down close to the ground. Even though most hardy geraniums are tough enough to handle the winter chill, it’s never a bad idea to tuck in your younger plants with a little evergreen brush or mulch to protect them from a deep freeze.
