Buddleja davidii is a rapidly growing, deciduous, drought-tolerant shrub native to Asia. Plant it in the full sun in well drained soil. It is easy to transplant and flowers on new growth which appear from summer through the first frost. The best flowers appear when plant is severely pruned in late winter.
Butterfly bush care is easy. Water the shrub slowly and deeply during prolonged dry spells so that the soil absorbs the water deep into the root zone.
When we say full sun, we mean it – butterfly bush require a minimum of 8 hours of bright sunlight. Even in warm climates, plant them where they get no fewer than 6 hours of sun.
When planted in good quality garden soil, a butterfly bush rarely needs fertilizer. Fertilize with a little compost.
Bush grow best in an acid to moderately alkaline soil ranging from 5.5 to 8.5 on the pH scale. Most average garden soils fall between a pH range of 6.0 to 7.0. Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark.
Butterfly bushes do not need to be pruned every year. In fact, you only need to prune them when they get too large for the space allotted. But since butterfly bushes only bloom on new growth many gardeners prune them severely each spring to encourage lots of new growth and lots of flowers.
In winter, butterfly bush is semi-evergreen as long as temperatures don't drop below 20 degrees F, but they can tolerate colder temperatures. In summer, temperatures up to 90 degrees F are safe, but anything over this causes new flower buds to stop developing.
