Herbaceous layer · Nitrogen-fixing legume
Lupin
Lupinus spp. (incl. L. arboreus / garden hybrids as appropriate)
Nitrogen-fixing herbaceous or shrubby legumes used for soil building and bee forage. Choose sterile or non-invasive types and follow local weed guidance.
Also known as: Lupin, Tree lupin (where used), Garden lupin
Layer
Herbaceous layer
Climate
Warm temperate, Temperate, Cool temperate
Sun
Full sun.
Water
Moderate; many species dislike waterlogging.
Soil
Free-draining; often tolerate poorer sandy soils.
Size
0.5–2 m depending on type H · 0.4–1.5 m W
Growth
Fast
Frost
Varies by species; many garden lupins are frost hardy; tree lupin more coastal.
Edible uses
Not primarily grown for direct human food on this site’s guidance.
Harvest window
Flowering spring–summer; cut for biomass as needed
Ecological functions
Nitrogen fixation · Bee forage · Soil building · Nurse biomass
Wildlife value
Excellent bee forage
Human uses
Green manure / chop-and-drop · Ornamental insectary
Propagation
Seed (often with inoculation); check local species advice.
Maintenance
Cut for mulch before seed set if containment is needed; follow regional weed rules for tree lupin.
NZ growing notes
Useful fertility plants, but some lupins (notably tree lupin) are weedy in parts of NZ — check local status before planting and prefer contained garden types.
In the food forest
Lupin is a herbaceous nitrogen and bee plant for sunny edges and nurse strips. Use it as biomass and fertility support, not as human kai.
Establishment
Sow appropriate non-weedy types into free-draining sunny ground. Inoculate seed if recommended. Cut for mulch before unwanted seed set.
NZ honesty
Climate fit is broad; biosecurity honesty is not. Confirm your species is acceptable locally — tree lupin is problematic in some coastal districts.
Suitable NZ regions
Companion plants
Related guilds
References
- NZ weed and farm forestry guidance — Species choice and containment matter — verify locally.