Blue Bush Lupine is a very fast growing shrub related to the annual Lupines that I remember seeing lots of in gardens in the UK. The shrub form just happens to be larger and longer living, both forms retain the toxic stems, leaves and seeds. Birds, bees and butterflies love the flowers so it’s still a great wildlife plant.
While this plant is native to California it is considered invasive in parts of the state. It has been planted in some coastal areas to stabilize sand dunes but due to it’s fast growth, high percentage of surviving seedlings and ability to create it’s own nitrogen in nutrient poor soil it has quickly taken over such areas and is very difficult to remove. One of the most impressive biological functions of Lupines, and indeed most other plants from the Fabaceae family, it hosts bacteria in it’s roots called “Rhizobia”. This bacteria takes nitrogen gas from the air and converts it into a form in the soil that plants can feed on. They can’t create their own water though so don’t worry about them taking over the world. They ain’t Triffids.
I’m still a bit confused about the scientific naming. When I bought the seeds from Larner Seeds they were labeled Lupinus Propinquus. This is the name I’ll be sticking to in my journal. However it looks like they are now called Lupinus Arboreus even though that name is more commonly associated with the yellow form of Bush Lupine. Perhaps it has been agreed that color alone is not enough to differentiate between species and as such the two plants now share the same botanical name?
Blue Bush Lupine is native from Ventura County north all the way through Washington State. It likes full sun near the coast, occasional water and in the right conditions it will grow to 4′ or 5′ high with a similar spread. The blue flowers appear in late spring and early summer with many seed pods following in the autumn.
|Common Name||Blue Bush Lupine|
|Botanic Name||Lupinus Propinquus|
|Potential Size ||3' x 3'|
|Notes||Attracts ButterfliesAttracts Bees|