There is still a bit of time until the late-flowering shrubs finally start to green up after the cold winter. Buddleias (Buddleia) can be particularly hard hit because many of the bushes are dead to the ground and the only signs of green growth come from the base of the plant or even the roots. How to save buddleia after frost damage, read on and follow our tips!
What kind of frost protection does the buddleia need?
If you grow your shrub in the garden, it needs frost protection made from brushwood or leaves for the first three years. Ground cover can be used as natural frost protection. After the shrub is established, you can plant it at knee height from the second year onwardscut back in spring. When it comes to older plants, the above-ground parts may freeze over the winter, but then the roots produce the new growth.
If your shrub is grown in a container, it will be subject to frost damage because it will not receive enough heat due to the limited amount of soil. It is therefore advisable to overwinter a potted buddleia in a room where it is not threatened by frost damage.
How do you know if your plant is frostbitten or not?
If yoursBuddleia well establishedfrost doesn't bother him either. Frost damage usually occurs when a period of extremely cold weather strikes in late winter after a period of mild weather. Then the ornamental shrub can freeze severely. You can do a test to see if your buddleia has frostbitten. This is how it works:
Use a sharp, disinfected knife to scrape off some of the browned bark on the branch. Then remove only a small portion of the bark so that the underlying tissue is clearly visible. If it's green, your shrub is still alive. But if you see brown tissue, it means the branch is frostbitten.
In colder climates, Buddleia grows like a perennial. The shrub is blooming on new wood this year, so you may finally get some flower heads, but because of the cool spring and previous stressthrough the coldthey appear later than usual. What to do to save buddleia after frost damage? The only thing you can do now is cut out the dead areas and hope they grow back.
How to prune in spring?
As a rule, buddleias should be pruned in early spring when the first new growth appears on the lower trunks - you can cut them back to 30 to 45 cm above the ground. Don't prune them in the fall when you're doing the rest of your gardening. Their gray-green stems and vestigial leaves look beautiful in winter. The plants self-seed; if you are concerned about them becoming invasive, cut off the seed heads in the fall.
What you shouldn't do to a frozen buddleia?
Do not fertilize frost-damaged plants
You may be tempted to fertilize your damaged plants to bring them back to life, but you shouldn't do that, experts advise. Fertilizer is likely to do more harm than good, especially given the stress the plants have endured. Buddleia usually grows well on fallow land with low fertility. Keepthe damaged plantsKeep an eye on them throughout the summer as they will continue to be under stress when we inevitably get hot weather and extended periods without rain.
Mulch can harm your perennials
While most plants benefit from a thick layer of mulch in winter, this can worsen winter damage to buddleia bushes. The key to getting a buddleia through the winter is well-drained soil, especially when temperatures are low but the ground is not frozen. Because mulch retains water in the soil, heavy application of mulch can lead to root rot. In cold climates, it is best to place a light layer of mulch over the roots. Make sure the few centimeters immediately around the center of the plant are bare and free of mulch.