Lupinus, Family Fabaceae
Blue Bonnet, which refers to the annual lupine.
Lupines can grow up to five feet tall, with flower spikes as long as 18 inches long.
Lupines bloom over a two-month period, which can range from May to July, depending on the variety and the growing zone.
The dense floral spikes of lupines may grace your flower garden in shades of purple, pink, red, white, and yellow. The foliage resembles palm leaves, with seven to ten leaflet segments each.
Although rainbow hybrid lupine seed mixes are the most popular commercially available lupine, the original blue strain is the hardiest. Over time, the blue lupines in a rainbow mix will persist and perennialize, while the less adaptable colors die out.
Lupines need neutral to slightly acidic soil, although they can grow in very acidic soil conditions. Lupines don’t need rich loam, but it’s important to grow the plants in very well-draining soil to avoid root rot. Sandy soil conditions and poor rocky soil promote the growth of the lupine’s deep tap root.
Starting lupines from seed is an economical way to get a showy flower garden the following season. The seed coat is tough, and seeds have a better germination rate if you nick the seed coat or soak them in water overnight. Plant them about ¼ inch deep outdoors, as they do not transplant well. Expect germination in 14-30 days.
- Russell mixed colors: Hybrid rainbow and bicolor mixture
- Lupinus polyphyllus: The species sold in wildflower mixtures; all blue flowers
- Gallery series: Dense flower spikes on a compact plant, growing no more than two feet tall