Growth Characteristics

• Depending on its variety, the butterfly bush can grow to a maximum height of 15 feet, and performs best outdoors in USDA hardiness zones 5 to 9. Clemson Cooperative Extension states that extreme cold can kill the plant down to soil level, but no long-term harm is done, as new shoots will sprout from the crown in the spring.
  
  

Growth Requirements

• This plant needs soil with a neutral pH, or acidity level, from 5.5 to 7 but will tolerate slightly more alkaline soil. It prefers well-drained sandy to clay loam. It is not bothered by pests other than spider mites which might appear during dry spells.
  
  

Propagation

• The butterfly bush self-propagates by sending out roots from which new plants sprout, which makes it a problem in some areas. Giving it plenty of space and promptly removing new shoots where they aren't wanted should keep it controlled.
  
  

Uses

• Butterfly bushes are popular choices for wildlife gardens, specifically in gardens whose owners are trying to attract butterflies. Their colorful flower spikes, particularly the red varieties, are also very appealing to hummingbirds.