Subalpine lupine
The blue lupine that fills Mount Rainier's Paradise meadows in summer and quietly rebuilds raw volcanic soil by pulling nitrogen from the air.
Subalpine lupine at a glance
Lupinus latifolius sub-AL-pine LOO-pin; Lupinus latifolius is loo-PY-nus lat-ih-FOH-lee-us
- Type
- Plant · wildflower
- Diet
- Producer
- Size
- Knee-high, up to about 2 feet, in spreading patches that can color a whole meadow blue.
- Lifespan
- A perennial that dies back to the roots each winter and returns for many years.
- Conservation
- Not formally assessed by IUCN; common in Pacific Northwest mountains
Like all green plants it makes its own food from sunlight. It also carries bacteria in its roots that pull nitrogen out of the air and turn it into plant food, so it can grow in poor, raw ground where little else will.
Is it safe to touch?
Do not eat any part of it. Lupine seeds and pods contain natural toxins that can make a person sick. It is safe to look at and smell, just not to taste, and it is best left growing for the next hiker to enjoy.
For a few weeks each summer the meadows at Paradise on Mount Rainier turn blue. The color is lupine, thousands of knee-high spikes of pea-shaped flowers opening at once when the snow finally clears in July, so thick in places that they wash the green slope in violet all the way to the tree line. People fly across the world to stand in it. What almost none of them notice is that the flower doing the showing off is also doing the hardest work on the mountain.
Volcanic ground starts out as raw gravel and ash, poor in the one thing plants need most, nitrogen. Lupine gets around that. Down in its roots it houses colonies of bacteria that pull nitrogen straight out of the air and hand it to the plant as food, so lupine can take hold in bare mineral soil where almost nothing else will grow. As it lives and dies it leaves that nitrogen behind in the ground, and slowly the raw gravel becomes soil rich enough for the grasses, paintbrush, and asters that fill in around it.
Every part of it is worth a close look and none of it is worth a taste, since the seeds carry a toxin that can make you sick. Kneel instead and turn over a leaf shaped like a small green hand, and after a rain you will find a single bright bead of water held at its center, the whole meadow catching the sky one drop at a time.
Did you know?
- Its roots host bacteria that pull nitrogen straight out of the air and turn it into fertilizer, so lupine can move into bare volcanic gravel and start building soil for other plants.
- The leaves are shaped like little green hands, and after rain each one holds a bright bead of water at its center.
- It is one of the wildflowers that paints the meadows at Paradise on Mount Rainier, where the short summer bloom draws people from around the world.
Common questions
Why is lupine important in the mountains?
It fixes its own nitrogen, meaning it can grow in bare, poor volcanic soil and slowly enrich the ground. That makes room for other meadow plants to move in behind it.
Can you eat lupine?
No. Lupine seeds and pods hold natural toxins that can make people sick. Enjoy it with your eyes and nose, but never taste it.
When do the lupine meadows bloom?
In the short mountain summer, usually July and August, when the snow has finally melted off the high meadows like Paradise on Mount Rainier.