When springtime lupines blossom and generate colorful spikes in gardens, wildflower observers all around the world rejoice. The shape and color of hybrid lupines aren't subtle at all. The unmistakable look is a tall, showy spire of flowers, which can appear in various colors. With seven to ten leaflet segments per leaf, the foliage resembles palm leaves.
This fast-growing flower is available as an annual as well as a perennial that is typically potted. When starting with a new plant or cuttings, it's better to plant them in the spring, but seeds can be sown in the late spring or fall. It's important to remember that the plant is poisonous to both humans and animals.
The hybrid crosses (Lupinus hybrida) of diverse native species planted in gardens are produced to increase bloom color and vigor. Lupinus is a large flowering plant genus that includes hundreds of species. Lupinus polyphyllus, a Northernmost American native, was combined with numerous other species, including Lupinus arboreus, to create the colorful hybrid lupines that are so popular in gardens.
Lupine blooms were previously thought to absorb all of the nutrients from the earth, hence their common name, which is derived from the Latin word for wolf. On the other hand, Lupinus plants are members of the Fabaceae family of plants, and like peas, they can fix nitrogen in the soil. They make excellent garden border plants, though some taller species may require staking to avoid flopping over. To prevent having to tie individual stems to stakes, use grow-through grid stakes.
The original blue strain is the hardiest, although rainbow hybrid lupine seed mixes are the most common commercially available lupine. Lupines take very little attention when grown in their ideal conditions. To encourage more blooming, be sure to deadhead your plants (remove spent flowers). During periods of dry weather, make sure to water them.
Lupines grow and blossom best in full sun, with at least six hours of direct sunlight on most days. They can tolerate light shade, although flowering will be reduced. In warmer areas, though, some afternoon shade is ideal. Lupines rarely flower if they are planted in deep shade. Trim back nearby bushes and trees to allow some sunlight to reach the lupines in shaded areas.
These flowers prefer soil that is rich in organic matter and has good drainage. They like a neutral to slightly acidic soil pH, but they can even thrive in extremely acidic soil.
While lupines dislike damp soil, which can promote root rot, they prefer to be watered regularly. If there hasn't been any rain, water at least once a week to keep the soil from drying out.
Humidity and Temperature
Lupines prefer relatively cool summers. They don't thrive in hot, humid temperatures like those found in the southern United States. Plants that are exposed to a lot of heat and direct sunshine may not be able to blossom. A small layer of mulch around the lupines can assist conserve soil moisture and keeping the roots cool in warmer areas.
Lupines don't need fertilizer in most cases, and too much fertilizer can promote excessive foliage development at the price of blossoms. An acidifying fertilizer, on the other hand, can help decrease the pH of alkaline soils.
Lupine's Different Types
There are various lupine types available, each with its distinct appearance, such as:
- Russell mixed colors: This hybrid rainbow and bicolor mixture, bred in 1937 and naturalized in many locations, is the foundation for all future cultivars.
- Gallery series: The small plant's dense flower spikes are no more than 2 feet tall.
- 'Dwarf Lulu': This plant grows to about 2 feet tall and has extraordinarily dense racemes. It comes in a spectrum of colors.
- 'Minarette': This 18-inch variety looks great in drifts along the edge of a border or in containers.
This is the most common way of cultivating lupines since they sprout so easily from seed. In the spring, however, lupines can be grown by carefully taking basal cuttings from existing plants. Sever a segment of crown and roots from the parent plant with a sharp knife and transplant it to a new location.
This should be done in the early spring before the plant begins to grow and leaf out actively. Lupines are short-lived plants, so it's a good idea to propagate them every two to three years.
Lupine Seed Growing Instructions
Starting lupines from seed is a cost-effective way to have a colorful flower garden the next following season. They are one of the most straightforward perennials growing from seed. Seed-grown perennial lupines are unlikely to bloom until their second year.
Because the seed coat is tough, nicking it or soaking it in water overnight improves germination. Plant the seeds a quarter-inch deep outdoors in a permanent location that gets plenty of suns. Lupines are difficult to transplant because of their long taproots. It should take 14 to 30 days for the seeds to germinate.
Common Plant Pests and Diseases
Lupines are susceptible to a variety of insects and diseases. Slugs and snails, as well as aphids, commonly appear in the spring. As soon as you notice pests, use horticultural oils or pesticides to control them.
Brown spot fungus can affect lupines, causing brown patches on different parts of the plant. Remove and destroy affected plants. Remember not to plant lupines in the same area for several years to allow the spores to die off.
Powdery mildew can also affect lupines, particularly if there isn't enough air circulation around the plants. This fungal disease causes white patches on the foliage, and it can be controlled with various chemical and organic methods. You can also cut the foliage away and wait for it to regrow.