If you’re searching for an eye-catching, summer-blooming perennials that will stand out from the crowd, lupine is a definite bet.
Striking โplants have stiff, erect flower spikes โ 1 to 4 feet tall โ that emerge from horizontal foliage. โFlowers are similar to those of peas or sweet peas and grow in large, โdensely packedโ racemesโ of deep blue, purple, yellow, pink, or white.โ
A short-lived perennial, lupine is found from California to British Columbia. Plants do not require a lot of care. Give them a sunny spot, ample water, and well-drained soil and youโll be hearing oohs and aahs for seasons to come.
Lupines make โa terrific addition to borders, xeric (water conserving) gardens, or scattered throughout native landscapes.
Depending on the variety and your zone, lupine flowers will bloom from late spring through the first weeks of July.
As a result, we recommend planting them with some late-blooming, summertime favorites โ zinnia, rudbeckia, daisies โ to keep the color going well into fall.
Plants are deer-resistant โand โtheir flowers attract many important pollinators like bees, butterflies, and hummingbirds.
Botanical Name: Lupinus
Family: Fabaceae
Plant type: Herbaceous, perennial, annual
Hardiness zones: 4-8 (USDA)
Sun exposure:ย Full sun to light shade
Soil type: Rich, moist, well-drained
Bloom time: late spring to early or midsummer.
Maturity:ย Days to bloom varies depending on fall or spring planting; blooms July-August
Height:ย 1 to 4 feet, depending on variety
Spacing:ย 12 inches
Flower color: Purple, blue, yellow, pink, and white.
Quick Guide: Planting, Growing & Caring for Lupine
- Purple color is most common, but blue, yellow, pink, and white varieties are also available
- Prefers cooler regions with average soil
- Plant in full sun to light shade; loosen soil for long taproot to grow
- Plant chilled seed in spring otherwise, fall planting is preferred for seed and plants
- Transplanting is not recommended
- Blooms late spring to mid-summer
Lupine Care
Lupines are members of the Lupinus genus, which belongs to the Fabaceae family of plants. The genus has more than 199 species.
They are referred to as โlupinโ plants and are also known as โbluebonnetsโ in some areas.
Lupine hybrids (Lupinus hybrida) are commonly grown in gardens across the country and are bred to maximize flower color.
The most popular hybrid lupines for gardens were created by crossing Lupinus polyphyllus, a North American native, with many other species, including Lupinus arboreus.
Domesticated lupines come in a variety of colors, including blues, yellows, pinks, and purples, in contrast to the blues and whites found in wild lupines.
They are valued not only for their beauty, but also for their ability to grow in harsh conditions, such as sandy soils with few nutrients, high elevations, and places with cool summers.
In fact, lupines are members of the pea family, making them legumes that are nitrogen-fixing and can improve โyour soilโs fertility over time.
Light
Lupines grow and bloom best in full sun, with at least six hours of direct sunlight on most days.
They can tolerate mild shade, although blooming will be reduced. In hot climates, though, some afternoon shade is preferable.
Lupines seldom blossom if they are planted in heavy shade. Trim back nearby bushes and trees to enable some sunlight to reach the lupines in shaded areas.
Soil
Lupines prefer cool temperatures and moist, sandy, well-drained soil. They grow best in soil with a pH that is neutral to slightly acidic, but they can also grow in very acidic soil.
Water
Keep the soil evenly moist after planting lupines to encourage good root development. But remember that lupines donโt prefer soggy moil as overwatering can lead to root rot.
Your plants will be able to survive drier conditions once they have established a strong root system and will only need to be watered during periods of drought
Temperature and Humidity
Lupines prefer climates with fairly cool summers and donโt do as well in hot, humid conditions, like that of the Southern part of the United States.
Plants that are exposed to a lot of heat and direct sunshine may not be able to flower.
When growing in hot climates, make sure to place a light layer of mulch around the lupines to help its soil retain moisture which can keep the roots cool
Fertilizer
Lupines can absorb nitrogen directly from the atmosphere, therefore plants may thrive on nitrogen-deficient soil without the need for additional fertilizer. In fact, too much fertilizer may lead to excessive foliage growth instead of flowers blooming.
An acidifying fertilizer, on the other hand, can be helpful in decreasing the pH of alkaline soils to help lupines grow better.
Pruning and Deadheading
Deadhead your plants, i.e., remove spent flowers, to encourage a second bloom in early fall, especially if you live in an area with cool summers. Perennial species of lupines can be pruned down to the ground as the foliage begins to yellow at the end of the season.
How to Plant and Grow Lupines
Lupines are herbaceous perennial plants and can be grown from seeds, cuttings, or divisions. Each year, the lupine’s foliage dies back to the ground, and new growth emerges from the roots below in the spring.
With the right lighting, lupines can also be grown indoors in containers. To learn more about how to grow plants indoors, check out our complete indoor gardening guide.
Site Preparation
Easy to grow, lupine thrives in cool, moist locations. It prefers full sun to light shade and average soils, but will tolerate sandy, dry soil. Plants develop long taproots, so loosen the soil to a depth of 12-20 inches using a rototiller or garden fork. They will not grow in clay.
How to Grow Lupines from Seed
If growing from seed, germination is greatly increased by a 7-day cold treatment (see our article onย Seed Stratification). Place seeds and slightly damp paper towels in a Ziploc bag and store them in the refrigerator.
Another method would be toย soak them in warm waterย for a 24-hour period. Treated seeds can be directly sown into a seedbed in spring or summer until August 1st.
Sow seeds at a shallow depth of about 1/4 inch beneath loose topsoil, and 12 inches apart, and keep them evenly moist until the seedsย germinate. Seedlingsย should emerge about 15 to 25 days after planting.
The best time to plant untreated lupine seeds outdoors is between September-November.
Plants grown from seed will bloom in their first year. Pinch off spent flowers to prolong the blooming period. Apply anย organic fertilizerย once per month to promote healthy plants and large blooms.
Tip:ย For dramatic results, mass lupines in borders or scatter them throughout the cottage garden. Visit ourย Flower Gardening 101ย article for more information.
Propagating Lupines
To grow from cuttings, take a stem down to the trunk, including a bit of its โfootprintโ connection to the trunk. Set in moist, very well-drained, gritty sand or otherย propagation mediums.
Keep covered during the propagation period except for several minutes each day to air and allow the plant to adjust.
Start cuttings in larger pots that can be transplanted into the outdoors, pot and all, so as not to disturb the roots.
Doย NOTย transplant as the long tap root is delicate, and if damaged, the plant will fail.
Seed Saving Instructions
Ripe seed pods naturally explode. When the pods begin to turn yellow and the seeds โrattleโ inside, they are ripe. Place in a screen box where they can burst freely and simply pick up the seed. Read more aboutย saving seedsย here.
Common Pests & Plant Disease Problems
Lupines are vulnerable to aphids in spring, as well as slugs and snails. When found, respond to pests with horticultural oils as soon as possible.
When it comes to aphids, hereโs the least-toxic approach to pest control:
- Pinch or prune off heavily infested leaves or other plant parts.
- Get commercially available beneficial insects,ย likeย ladybugs, as they are important naturalย predators of the pest.
- Applyย organicย Diatomaceous Earthย (DE)for lastingย protection. Containingย NOย toxic poisons, DE worksย by scoring an insectโs outer layerย as it crawls over the fine powder.
- A short-lived natural pesticide,ย Saferยฎ Soapworks fast onย heavy infestations.
- Do not over-fertilize โ aphids like plants with high nitrogen levels and soft new growth.
Brown spot fungus can affect lupines, causing brown patches to appear on different areas of the plant.
When that happens, eliminate and kill all infected plants, and refrain from cultivating lupines in that location for at least a few years to give the spores enough time to die off.
Powdery mildew can also affect lupines, particularly if there isn’t goodย air circulation around the plants.
This fungal disease causes white, powdery areas on the leaf, and it may be controlled using a variety of chemical and organic techniques. You may, alternatively, cutย the foliage away and wait for it to regrow.
