Common Name: Blue Lupine

General Information

Lupinus nootkatensis is a stout, herbaceous perennial plant growing from a thick, rhizomatous rootstock; it can grow up to 70cm tall[].
The plant is harvested from the wild for local use as a food. It is sometimes used as a green manure and soil improver, and is also sometimes grown as an ornamental in gardens[].
Lupinus nootkatensis is a widespread and common species in its natural range and at present there are no major known threats to the species. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

Lupinus species in general (and especially the seeds) contain a range of bitter-tasting alkaloids such as lupine, anagyrine, sparteine and hydroxylupanine. The pharmacological effects of these alkaloids are that they block ganglionic transmission, decrease cardiac contractility and contract uterine smooth muscle[]. When ingested in moderate to large quantities they can cause symptoms such as respiratory depression and slow heartbeat, sleepiness and convulsions[].
Alkaloid levels can vary greatly from species to species, and several members of the genus are used for food. In some species low-alkaloid, sweeter-tasting varieties have been developed. There are also techniques (particularly soaking and discarding the soak water) that lower the alkaloid levels.
Unless it is known that the plant is low in alkaloids then caution should be applied to any ingestion of the plant[].
Fungal toxins can readily invade the crushed seed and can cause chronic illness[].

Botanical References

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Range

North-western N. America - Alaska, Yukon Territory, British Colombia

Habitat

Roadsides and open banks[]. Clay or disturbed soil along highways, fields, vacant lots, and other waste areas, such as eroded or overgrazed meadows, yellow pine, and sometimes in Pinyon-Juniper ranges; at elevations from 1,500 - 2,500 metres[].

Properties

Conservation Status	Least Concern
Edibility Rating
Other Uses Rating
Habit	Perennial
Height	0.70 m
Pollinators	Bees, Insects
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Lupinus nootkatensis is a very cold-hardy plant, able to tolerate temperatures down to around -30°c when fully dormant[].
An easily grown plant, succeeding in any moderately good soil in a sunny position[]. Members of this genus are mainly found in dry habitats, often on stony and low fertility soils[]. This species, however, is more common on moister, but well-drained, soils[].
This species is very susceptible to slug damage, the plant has been cultivated as an ornamental, but has virtually died out in the garden though it grows well in the wild in Scotland[].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

Seed - cooked[]. Used as a protein-rich vegetable or savoury dish in any of the ways that cooked beans are used, they can also be roasted or ground into a powder. If the seed is bitter this is due to the presence of toxic alkaloids and the seed should be thoroughly leached before being cooked[, ].

Root - raw or cooked[, ]. Peeled and then eaten raw or boiled[]. The roots are harvested in the spring and are then roasted before being eaten[]. The roasted root can be dried, ground into a flour and then stored for later use. The raw root should not be eaten since they contain toxic alkaloids and will cause a drunken-like state if eaten in excess, but the cooked root is safe to eat[, ]. Some Native American tribes considere the roots to be wholesome when properly prepared, whilst others consider it to be toxic[].

Seedpods - cooked[]. The seedpods are around 5cm long and 1cm wide, containing around 4 - 6 seeds[].

Medicinal

None known

Agroforestry Uses:

The plant has been grown for some decades as a green manure and soil improver in Iceland. It has also been trialed in Alaska for reforestation purposes[].

Other Uses

The water used to leach alkaloids from the seeds of bitter forms of this plant is rich in alkaloids and can be used as an insecticide[].

Propagation

Pre-soak the seed for 24 hours in warm water and then sow in early spring in a greenhouse[, ]. The seed is best sown in individual pots since the plants strongly resent root disturbance. Germination should take place within a couple of weeks. If sown in trays, then the seedlings should be potted up into individual pots as soon as they are large enough to handle. Plant out in early summer when the plants are around 15cm tall.
It should also be possible to sow the seed in situ in mid to late spring. Protect the seed from mice.
Basal cuttings, mid spring in a cold frame. Harvest the shoots when they are about 10cm long with plenty of underground stem. Pot them up in a very sandy soil in individual pots and keep them in light shade in a cold frame or greenhouse until they are rooting well. Plant them out in the summer.
Division in early spring. Difficult.
Lupin propagation is usually carried out by seed - vegetative propagation is normally only used when propagating named cultivars[].