To answer Pamela, here is when and how I prune my Buddelja :
- Buddleja officinalis blooms in south of France between january and march, according to weather. I prune it between april an june, but not after. The new branches are going to grow during the summer, and buds begin to appears on this new branches in automn, from october if the weather is soft. B. officinalis is a shrub of 3 m tall in my garden, and I prune it to keep in this proportions. So, I prune hard, and reduce until about 2 meters/ 2,5 meters. It's largely sufficient.
- Buddelja myriantha is much lower, and form a beautiful round busch of less of 1 meter. I prune it very softly, only the extremity of branches, only to eliminate the faded flowers. I do that in september or october, when I have the time, and it form fast new foliage grey white in full sun.
- Buddleja madagascariensis is very differents. In a first time, I pruned it at the end of spring, and very hard because I wanted keep it not too tall. It's impossible ! This buddleja is very vigourous and grows in a muddled way. I transplanted it this year at spring, and I intented to let it grow in tree without cutting. We shall see ...
There is an other shrub so interesting wich seem strangely to Buddleja davidii : Vitex agnus castus. It blooms blue, like Buddleja daviddi, but it is not a buddleja (family : Verbenaceae), and it attracts also the butterflies and much other insects. I think it's very important for the variety of the ecosystem of our gardens.