We lupines are particular about our real estate. To truly thrive, we require a location that receives full sun for at least six hours a day. This abundant sunlight fuels our magnificent flower spires. The soil is even more critical; we demand well-draining soil. Our long taproots are prone to rot in heavy, waterlogged clay. If your garden soil is dense, please amend it generously with compost or gravel to improve drainage. Most importantly, we prefer a slightly acidic to neutral soil pH. Alkaline soils will cause our leaves to yellow, a condition called chlorosis, as it locks away the iron we need.
Our seeds possess a hard outer coat, a trait that protects us but makes germination a challenge. To successfully sow us, you must mimic the natural scarification of a winter spent in the ground. Gently rub our seeds between sheets of sandpaper or soak us in warm water for 24 hours before planting. Sow us in the fall for a natural cold period, or start us indoors in peat pots 6-8 weeks before the last frost. We resent having our taproots disturbed, so transplant us carefully, ensuring the crown of the plant sits level with the soil surface.
While we are somewhat drought-tolerant once established, thanks to our deep taproots, we perform best with consistent moisture, especially during our active growth and blooming period in spring and early summer. Water us deeply at the base to encourage root growth and avoid wetting our foliage, which can invite fungal diseases. As for food, we are light feeders. In fact, we are legumes and have a symbiotic relationship with rhizobia bacteria that allows us to fix nitrogen from the air. A top dressing of compost in early spring is usually all the nourishment we require; too much fertilizer, particularly high-nitrogen blends, will promote excessive leaf growth at the expense of our beautiful blooms.
After our spectacular floral display fades, you can encourage a potential second, smaller bloom by deadheading—cutting down the spent flower spike to the base. This also prevents us from self-seeding excessively, which can lead to less-desirable hybrid colors if you are growing named cultivars. In late autumn, after the first hard frost, you can cut our foliage back to the ground. We will return in spring from our hardy crown. To propagate your favorite plants, division is possible but must be done with extreme care due to our sensitive taproot. The best method is to take basal cuttings from new growth in the spring.
We enjoy the company of other sun-loving perennials that share our soil preferences. Consider planting us alongside bearded irises, poppies, or alliums, which bloom concurrently and create a stunning display. Our main adversaries are slugs and snails, which find our new, tender growth irresistible. Aphids can also be a nuisance. Our primary fungal foe is powdery mildew, which can be mitigated by ensuring good air circulation around our foliage and avoiding overhead watering.
