Ten new varieties of sterile butterfly bush have been tested and approved. They’ll be available in garden centers in Oregon this spring. I’m going to buy some. They are handsome plants with long flowering periods, and they produce little or no seed. Plant breeders have succeeded in enhancing the desirable features of butterfly bush while eliminating it’s potential to be a noxious weed. Hallelujah!
I suspect gardeners are going to flock to these new varieties like butterflies to the flowers. The pictures are gorgeous, and the plants are more compact with shorter stems and bigger flower clusters.
The Oregon Department of Agriculture (ODA) developed a process in which nurseries can have their varieties evaluated. A 98 percent reduction in fertility is required for approval. The table below shows data for the most recent batch evaluated for Ball Ornamentals. The varieties in bold meet Oregon’s sterility standard. All of the approved varieties are complex interspecific hybrids--in other words, they can’t revert to the original species, Buddleia davidii, that has been the cause of so much concern in the past.
Mean fertility of control (fertile) cultivars was 7.32 seeds per capsule. The fertility reported for each cultivar is its relative fertility compared to 7.32 seeds per capsule. Cultivars in bold italics are exempt based on 98% reduction in fertility.
Cultivar % Fertility
FLUTTERBY GRANDÉ™ Blueberry Cobbler Nectar Bush 0
FLUTTERBY PETITE™ Lavender Nectar Bush 9.0
FLUTTERBY™ Peace Nectar Bush 122
FLUTTERBY™ Pink Nectar Bush 2.0
FLUTTERBY™ Lavender Nectar Bush 50
FLUTTERBY PETITE™ Dark Pink Nectar Bush 13.1
FLUTTERBY PETITE™ Snow White Nectar Bush 0.4
FLUTTERBY GRANDÉ™ Peach Cobbler Nectar Bush 0
FLUTTERBY PETITE™ Blue Heaven Nectar Bush 5.6
FLUTTERBY™ Mauve Pink Nectar Bush 5.9
FLUTTERBY GRANDÉ™ Tangerine Dream Nectar Bush 0.4
FLUTTERBY GRANDÉ™ Sweet Marmalade Nectar Bush 0
FLUTTERBY PETITE™ Tutti Fruitti Pink Nectar Bush 4.6
FLUTTERBY GRANDÉ™ Vanilla Nectar Bush 0
More sterile varieties are in the pipeline, and there should be plenty of choice for gardeners in the future. You can find the complete list of the approved varieties at:
Breeding out invasiveness is a new concept; I hope it catches on. There are quite a number of other ornamental plants that have weedy tendencies. If would be nice if gardeners could enjoy them now without causing noxious weed problems for future generations.