Garden Talk: March 25, 2010 From NGA Editors Japanese spirea
(Spiraea japonica) is an attractive and widely used landscape
shrub. But like some other garden staples such as barberry,
burning bush and Norway maple, it can be invasive in areas of
the eastern United States, crowding out native plants and
disrupting ecosystems. But ecologically responsible gardeners
may not need to say goodbye to this useful plant entirely.
Recent research at Montana State University has identified three
sterile cultivars of Japanese spirea, ones that do not set seed
and therefore cant spread and become a threat to native
vegetation. Crispa is a 2-3 tall shrub with deep pink flowers
and twisted crinkled foliage; Darts Red has deep,carmine-red
flowers and pinkish-red new growth on a 2-3 tall shrub; Neon
Flash is of similar size, with bright neon-red flowers that are
produced over a long period. (You may see these listed as
Spiraea x bumalda cultivars, instead of S. japonica). To find
out which plants are considered invasive in you