Lupins are a group of flowering plants that are easy to recognise since all varieties produce clusters of flowers along erect spires. Many are sweetly scented and have a pealike appearance. Lupins come in a vast array of colours including white, pink, red, violet and purple. A cottage garden favourite for several centuries, lupins are easy to grow from seed but germination is best done indoors about six to eight weeks before spring.
Fill up peat pots to within 1/2 inch of the top with seed starting mix.
Mist the seed starting mix with water until it is saturated. Avoid drenching the pots with water, as this will cause the pots to disintegrate.
Poke a 3/4-inch-deep hole in the centre of each peat pot, using a chopstick.
Scratch off a small section of the surface on each seed using a nail file or a piece of sandpaper.
Soak the seeds in a bowl of warm tap water for no more than 24 hours.
Plant one lupin seed in each peat pot, and cover each seed with no more than 1 inch of soil.
Transfer the pots to a moderately warm location that will stay between 18.3 and 23.9 degrees Celsius. Keep the mix in the peat pots on the moist side. Germination can begin in about two weeks, but can require as long as eight weeks.
Transplant the lupin seedlings into your flower garden as soon as they are about 2 to 3 inches tall.
Locate a sunny spot in your garden for planting the lupin seedlings.
Work the soil using a shovel, pick or fork to a depth of about 16 inches. Remove all weeds and their roots as you till the soil.
Spread out a 2- to 3-inch layer of sphagnum peat moss to acidify the soil. Lupins prefer being grown in soil that is acidic. You can also use elemental sulphur, provided you read the instructions on the product label so you know precisely how much to incorporate into the soil.
Dig planting holes that are as wide and as deep as the size of each peat pot. For annual lupins, make each hole about 6 to 10 inches apart. For perennial varieties, each hole should be between 18 and 24 inches apart.
Plant one lupin seedling into a planting hole. Use a trowel to push soil in and around each seedling.
Water each lupin seedling, taking care not to soak the leaves. Water the lupin seedlings daily for the first week after planting, then reduce watering to one to two times a week until established.
Fertilise perennial lupins in early spring; use a 10-10-10 or similar granular type fertiliser. Powdery mildew can form on the delicate foliage of lupins. To help prevent this, do not water in late afternoons.
Tips and warnings
- Fertilise perennial lupins in early spring; use a 10-10-10 or similar granular type fertiliser.
- Powdery mildew can form on the delicate foliage of lupins. To help prevent this, do not water in late afternoons.