Pink, violet, white, blue and even yellow – the popular buddleia delights the viewer with its summery blossoms. However, not all species and varieties of this perennial flowering shrub are hardy - so if you want to enjoy it for many years, you should know whether and what to do - and which varieties are most likely to survive a cold winter.
Which buddleia varieties are hardy?
Winter-hardy buddleia varieties are mainly Buddleja davidii and Buddleja alternifolia species such as 'African Queen', 'Black Knight', 'Dart's Ornamental White', 'Empire Blue', 'Ile de France', 'Purple Emperor' and 'Pink Delight'. These can withstand temperatures down to -20 °C and should be protected from frost, especially in the root area.
Which types of buddleia are hardy?
Probably the most commonly planted species are Buddleja davidii and Buddleja alternifolia, both of which are hardy after a certain period of time in the location and can tolerate temperatures of up to minus 20 °C. This applies to almost all varieties of the species mentioned, but only from around five years of age. However, freshly planted and younger specimens require light winter protection. On the other hand, rarer species such as the globe buddleia (Buddleja globosa), the Buddleja colvillei, which comes from the Himalayas, and the yellow buddleia (Buddleja x weyeriana) are absolutely not hardy. These buddleias should only be cultivated in pots; when planted out in the garden, they freeze and - in contrast to Buddleja davidii and alternifolia - do not sprout again.
The most beautiful winter-hardy varieties of Buddleja davidii
You can plant the following hardy varieties of Buddleja davidii in the garden without worry:
- ‘African Queen’ with its beautiful purple to violet-blue, very slender panicles
- 'Black Knight', very richly blooming with purple to dark purple flowers
- ‘Dart’s Ornamental White’, one of the most beautiful white-flowering varieties
- ‘Empire Blue’ with distinctive light purple flowers
- 'Ile de France' with probably the darkest flower color
- 'Purple Emperor' with very dark purple flowers
- 'Pink Delight' with beautiful silvery-pink flowers
In all of the varieties mentioned (although the list is of course not exhaustive, as Buddleja davidii is very rich in a wide variety of varieties), the shoots can freeze back in winter. However, this is no reason to panic, as after pruning in spring the bush will sprout again from the roots. It is therefore important that you protect the roots from frost, for example by mulching the root area.
Tip
Even if the selected variety is considered hardy, you should still overwinter it frost-free if it is grown in pots - here the plant does not have the ability to counteract the freezing temperatures.
