We want to enjoy its impressive blooms every summer. Thus, the question of the winter hardiness of butterfly bushes is obvious. Read here to what extent a butterfly bush tolerates frosty temperatures. Benefit from our tips for healthy overwintering in beds and tubs.
Well-rooted Buddleia is hardy down to -20°C
Winter hardiness builds up gradually
In contrast to native flowering shrubs, the Asian butterfly bush has to develop its winter hardiness from year to year. Only as an established, well-rooted plant does your Buddleja davidii in the bed have a frost tolerance of up to - 20 degrees Celsius. In the year of planting and in the following 3 to 4 years, you can help your bloomer with the following precautions:
- Leave fallen leaves in the fall
- Create a protective layer of 10 to 20 cm on the root disc with more leaves and brushwood
- Water a little in dry winter weather
Since the shoots are cut in late winter anyway, further measures are unnecessary at this point. If there are signs of delayed ground frost after the sprouting in spring, protect the young twigs from frost damage with a fleece cover.
Winter protection in the bucket is indispensable every year
In contrast to its conspecifics in the bed, a butterfly bush in the bucket is dependent on the following precautions every year in order to survive the cold season unscathed. How to do it right:
- Move the tub under a canopy or in front of a house wall before the onset of winter
- Place the jar on a block of wood and wrap in bubble wrap
- Cover the substrate with autumn leaves, wood shavings or straw
In regions with harsh winters, ideally place the pot in a sturdy wooden box with a bark mulch on the bottom. You can also fill the gaps between the wooden wall and the tub with mulch. Water the butterfly bush occasionally during the winter to keep the root ball from drying out.
tips
The limitation of winter hardiness to a base value of - 20 degrees Celsius does not affect the seeds. If a butterfly bush is given the opportunity to spread its seeds in the bed, the seeds will even survive the freezing frost. In order to prevent an invasive spread of the neophyte, cut off the withered flowers in good time in late summer.