Lupine: Direct Sow Perennial
How to Sow
Sowing Directly in the Garden:
- Direct sow in spring after danger of frost in a sunny location with well-drained, moist, slightly acidic soil. Sow where plants are to remain as they do not transplant well.
- Remove weeds and work organic matter into the top 6-8 inches of soil; then level and smooth.
- Sow seeds ¼ inch deep.
- Firm lightly and keep evenly moist.
- Seedlings will emerge in 14-28 days depending on soil and weather conditions.
- Thin to 18 inches apart.
How to Grow
- Keep weeds under control during the growing season. Weeds compete with plants for water, space and nutrients, so control them by either cultivating often or use a mulch to prevent their germination.
- Mulches also help retain soil moisture and maintain even soil temperatures. For perennials, an organic mulch of aged bark or shredded leaves lends a natural look to the bed and will improve the soil as it breaks down in time. Always keep mulches off a plant’s stems to prevent possible rot.
- Water thoroughly at least once a week to help new roots grow down deeply. Soil should be damp at about 1 inch below the soil surface. You can check this by sticking your finger in the soil. Water early in the morning to give all leaves enough time to dry. One inch of rain or watering per week is recommended for most perennial plants. You can check to see if you need to add water by using a rain gauge.
- Taller varieties may require staking.
- Plants bloom in summer, but if you cut the spent slower stalks back after blooming, the plants may reward you with a second flush of bloom in late summer or fall.
- Lupines are cool season plants that are at their best in areas with cool summer nights.
- These spiky plants are dramatic at the back of the border and beautiful for cut flowers.
- They naturalize well in wildflower meadows.
- The flowers attract hummingbirds and beneficial insects.
Common Disease Problems
Botrytis: This fungus causes a grey mold on flowers, leaves, stems and buds. It thrives in cool wet weather conditions. Burpee Recommends: Remove affected plant parts, avoid watering at night and getting water on the plant when watering. Make sure plants have good air circulation. Contact your Cooperative Extension Service for fungicide recommendations.
Cucumber Mosaic Virus: This virus disease is spread by aphids and causes mottling on the leaves, bunching and downcurling of young leaves, small leaves and brown streaking on the stems. Burpee Recommends: There is no cure for this disease. Remove and destroy infected plants. Control aphids which spread the disease. Be careful when working in the garden and do not touch any plant until you have washed your hands or gloves after touching infected plants. Clean tools after working with each plant.
Downy Mildew: This fungus causes whitish grey patches on the undersides and eventually both sides of the leaves. Burpee Recommends: Rotate crops with plants in a different family. Avoid overhead watering. Provide adequate air circulation, do not overcrowd plants. Do not work around plants when they are wet.
Powdery Mildew: This fungus disease occurs on the top of the leaves in humid weather conditions. The leaves appear to have a whitish or greyish surface and may curl. Burpee Recommends: Avoid powdery mildew by providing good air circulation for the plants by good spacing and pruning. Contact your Cooperative Extension Service for fungicide recommendations.
Root Rots: A number of pathogens cause root rots of seedlings as well as mature roots. Burpee Recommends: Practice crop rotation and do not plant related crops in the same area for several years. Pull up and discard infected plants. Make sure your soil has excellent drainage. Contact your Cooperative Extension Service for recommendations.
Common Pest and Cultural Problems
Aphids: Greenish, red, black or peach colored sucking insects can spread disease as they feed on the undersides of leaves. They leave a sticky residue on foliage that attracts ants. Burpee Recommends: Introduce or attract natural predators into your garden such as lady beetles and wasps which feed on aphids. You can also wash them off with a strong spray, or use an insecticidal soap.
Lupine Root Weevil: These insects feed on plant roots. The larvae are white curled worms feed on the roots interfering with their ability to take up water and nutrients. They overwinter in plant debris. Burpee Recommends: Handpick adults at night, shake the plants over newspaper to dislodge them. Check under pots where they hide during the day. Check with your Cooperative Extension Service for pesticide recommendations.
Slugs: These pests leave large holes in the foliage or eat leaves entirely. They leave a slime trail, feed at night and are mostly a problem in damp weather. Burpee Recommends: Hand pick, at night if possible. You can try attracting the slugs to traps either using cornmeal or beer. For a beer trap, dig a hole in the ground and place a large cup or bowl into the hole; use something that has steep sides so that the slugs can’t crawl back out when they’re finished. Fill the bowl about ¾ of the way full with beer, and let it sit overnight. In the morning, the bowl should be full of drowned slugs that can be dumped out for the birds to eat. For a cornmeal trap, put a tablespoon or two of cornmeal in a jar and put it on its side near the plants. Slugs are attracted to the scent but they cannot digest it and it will kill them. You can also try placing a barrier around your plants of diatomaceous earth or even coffee grounds. They cannot crawl over these.
Thrips: Thrips are tiny needle-thin insects that are black or straw colored. They suck the juices of plants and attack flower petals, leaves and stems. The plant will have a stippling, discolored flecking or silvering of the leaf surface. Thrips can spread many diseases from plant to plant. Burpee Recommends: Many thrips may be repelled by sheets of aluminum foil spread between rows of plants. Remove weeds from the bed and remove debris from the bed after frost. Check with your Cooperative Extension Service for pest controls.
Are lupines deer resistant? Unfortunately they do not tend to be deer resistant although they are not usually severely damaged.
Can I grow lupines in a container? We do not recommend growing them in containers as they are too large.
Will they continue to bloom if I deadhead them? In general lupines will bloom once, but may produce a second flush of bloom in late summer if cut back after blooming.
Do lupines self sow? They can if you allow them to go to seed. They offspring may not be true to type.
Why didn’t my lupine bloom? Lupines will not bloom the first year from seed.