Try the new dwarf form of butterfly bush, say experts with the University of Georgia Extension Service. These plants are about half the size of nondwarf types, and their fragrant midsummer flowers are attractive to butterflies. Petite Indigo butterfly bush (Buddleia davidii nanhoensis 'Mongo') has dark, lilacblue flower spikes. Petite Plum (B. Davidii nanhoensis 'Monum') has reddish-purple flowers with an orange eye in each floret. Both cultivars ultimately grow to about 6 feet.