Lupine flowers, pods, and leaves that I found in John Hendry Park in Vancouver

I love lupines. Their colourful flowers are borne on tall spikes and are a very noticeable and beautiful sight. The plants can be useful as well as ornamental.  In some varieties, the seeds provide us with food. In others, the seeds are toxic. Lupines are popular as cultivated plants in British Columbia and in many other places. The province also contains wild lupines that are native to the area.

Lupines (or lupins) belong to the family Fabaceae, which is also known as the Leguminosae family. Legumes are known as pulses in some parts of the world. The family also contains beans, peas, and lentils. The fruit of a lupine flower is a small pod, which contains the seeds. The seeds are released explosively when the pods are ripe. The ones that are edible are known as lupine or lupini beans.

A pink lupine (Photo by Mithos, CC BY-SA 3.0 license)

Cultivated lupines grow well in the southwestern part of British Columbia, where I live. They don’t do so well in areas with very hot summers. Most are perennials, but some grow as annuals. As in a pea flower, each lupine flower has five petals: an upper standard, two lateral petals, and two bottom petals that join to form a structure called a keel. The petal arrangement can be seen in the close-up photo of the pink lupine shown above.

The plants are known as sweet lupines or as bitter lupines, depending on the nature of their seeds. The seeds from bitter lupines contain a much higher level of chemicals known as alkaloids. These not only give the seeds a bitter taste but are also toxic. The seeds must be soaked for a long time in order to remove the alkaloids. The seeds of sweet or edible lupines don’t require a soaking before being eaten, though they may contain a low level of alkaloids.

Pickled lupini beans made from Lupinus alba seeds (Photo by Calapito, public domain license)

No one should gather lupine seeds for eating unless they are positive that the seeds aren’t toxic. Even when a particular plant or product is said to be a nontoxic type, it’s probably a good idea to sample just one or two seeds to begin with.

Large-seeded, sweet lupines are the type that are generally grown for food. The seeds from these plants are used to feed livestock. They are also appearing in products designed for humans. Like beans, lupine seeds are a good source of protein. They are also a good source of fibre, folate, thiamine, and a range of minerals. They are an excellent source of manganese. Flour and hummus made from lupine seeds are available in some places.

Lupines in New Zealand (Photo by NT Franklin, public domain license)

Although this article is primarily about lupines in British Columbia, I couldn’t resist sharing the photo above. Some gorgeous photos of lupines growing in wild areas of New Zealand have been taken. Beautiful swathes of blue, violet, and pink flowers appear in some areas of the country in the spring. Unfortunately, the situation is not as idyllic as it seems. The plants are not native but are cultivated plants that have become naturalized. They are considered to be an invasive species.

Lupines have palmately compound leaves, or ones with leaflets arising from a point at the tip of the petiole, or leaf stem. The pattern can be seen in the photo at the top of this article. The leaflets are oval and pointed.

Like other leguminous plants, lupines have nodules on their roots that contain nitrogen-fixing bacteria. These bacteria convert atmospheric nitrogen into a form that their plant host (and us) can use. The lupines provide the other nutrients that the bacteria need in order to survive. The relationship between the plant and the bacteria is often defined as mutualism because both organisms benefit.

A Lupinus polyphylus hybrid (Photo by Mithos7, CC BY-SA 3,0 license)

Wild lupines are common in British Columbia.  One of the species in the province is Lupinus polyphyllus (large-leafed lupine), which is native to North America. The species grows in the wild and is also grown as a cultivated plant, in which case it’s known as a garden lupine. I believe that the cultivated plant shown in the first photo in this article belongs to this species.

The plant is appreciated for its tall spikes of blue or violet flowers in late spring and early summer. It’s not a sweet lupine, so caution is needed with respect to where it’s planted if there are children or pets in a family. The pods are curved and hairy. The seeds are grey and have dark spots.

Cultivated versions of wild plants often have new characteristics due to controlled breeding and hybridization. The garden lupine has been used to create hybrid plants with a wide variety of colours and features. The ones shown above and below are examples.

The hybrid above is classified as a Russell hybrid or a Russell lupine. This type is very popular. George Russell (1857–1951) was an English gardener who was very interested in lupines and experimented in breeding Lupinus polyphyllus. He created many new varieties of the plant.

Lupinus polyphyllus ‘Edelknabe’ (Photo by Franz Eitzinger, CC BY-SA 2.0 Germany license)

In the wild, the large-leaved lupine in found in a wide variety of open and semi-open habitats. These include meadows, open forests, roadsides, clearings, streambanks, and even seashores. Its distribution is concentrated in the southern part of British Columbia, but it’s also found is a places in central BC and even in a few places in the northern part of the province.

I’m always happy to see lupines in flower near my home, whether they are wild or cultivated. Until recently, I always thought of the seeds as poisonous. Now that I know that edible ones exist, I’ll be on the lookout for them in stores.

References

• Nutrients in boiled lupine seeds from Self Nutrition Data
• Nitrogen fixation in legumes from New Mexico State University