Buddleja or sometimes spelled Buddleia is a genus of over a hundred plants the most popular is Buddleja davidii, there are also B. globosa, B. alternifolia, B. lochinch, and B. weyeriana among others.
Buddleja is a large bush also known as Butterfly Bush. It has fragrant flowers in purples and pinks which also attract butterflies and hummingbirds. It is from the Scrophulariaceae family of plants. The name is attributed to Reverend Adam Buddle (1662-1715) it was named by Linnaeus.
How to grow Buddleja or Buddleia:
Grow them in the sun or partial shade. Plant them in rich, moist but well-drained soil. It is easy and fast-growing. Deadhead flowers for more flowers. Cut back hard in spring to stop it overgrowing. It will flower in late summer. They are sometimes considered invasive. Buddleja self-seeds. But you can propagate from semi-ripe cuttings in summer or hardwood cuttings later.