Long a favourite in Italian cuisine, rapini is becoming better known to North Americans. Enthusiasts exult that with its bitter, peppery, nutty flavour this vegetable is the food of the gods.
Although rapini (Brassica rapa Ruvo Group) is also known, among other names, as broccoli raab, broccoletti and spring broccoli, it's not a broccoli at all, but rather a turnip that doesn't form an underground root. The entire upper plant—stem, leaves and buds, which look like miniature broccoli heads—is edible.
As well as being tasty, rapini is an excellent source of potassium, magnesium, calcium, iron and fibre, and vitamins A, C and K. Like all members of the cabbage family, it contains beneficial phytochemicals, which help protect against cancer. Rapini can be steamed or stir-fried, but for better flavour, colour and texture, it should not be overcooked—usually not more than two to five minutes. Young, tender growth can also be added raw to salads.
Grow rapini in cool weather, as hot temperatures will cause the plants to bolt (shoot up and go to seed). Rapini needs fertile, humus-rich, well-drained soil with a pH of 6 to 7. Prepare the row by digging in lots of compost, then rake in an all-purpose organic fertilizer, such as 5-5-5, according to package directions. If your soil is too acidic, add limestone to raise its pH. Plant 10 to 12 seeds per 30 centimetres, five millimetres deep in rows 45 to 60 centimetres apart. Protect the seeds with a floating row cover as soon as they are planted to help guard against a number of insect problems.
Keep the soil moist but not soggy until the seeds germinate. Once the seedlings are 2.5 to five centimetres tall, thin to 15 centimetres apart to encourage good-sized buds. Rapini will go to flower quickly if stressed in any way; they produce the best crop of buds under conditions facilitating steady, fairly rapid growth.
Seeds can also be started early in a cold frame or indoors in average room temperatures. Use a good-quality starting medium and sow two or three seeds per cell pack. Keep the soil moist but not soggy during germination. As soon as they sprout, move seedlings to a cool area (about 10°C) and place under grow lights or in front of a sunny window.
Before transplanting outside, harden seedlings off by gradually exposing them to direct sun and cooler temperatures, which will help them survive light frosts. Dig a hole a bit larger than the root ball and work in compost and organic fertilizer. Plant the seedling, firming the soil gently around the stem.