Growing broccoli

Virtually unheard of in American gardens 50 years ago, broccoli is now a cool-weather favorite. Broccoli is an excellent source of vitamin C and a good source of vitamin A. It contains folic acid, calcium and chromium and is rich in many plant compounds such as indoles and isothiocynates, which have been found to have strong cancer-fighting properties. Use this guide to growing organic broccoli and start enjoying the benefits of this home-grown super food.

Choosing a site

• Broccoli does best in temperate and cold climates but is adaptable to all climates with a cool winter.
• Broccoli prefers an open sunny position protected from strong winds. If finding a site sheltered from cold winter winds proves difficult, support young plants with sturdy cane.

Broccoli varieties

• There are two main types of broccoli – sprouting and single-headed. Sprouting broccoli produces numerous small, dense heads from sideshoots, while single-headed broccoli produces one large head on a central stalk.
• Below are two varieties that are easy to grow and highly productive in the home garden.

Green Sprouting Calabrese

• An old-fashioned heirloom broccoli with large, dark green central heads that give way to multiple side shoots once cut. An easy variety to grow that is productive in the home garden.
• Sun: Full sun
• Spread: 12 inches
• Height: 24-30 inches
• Days to maturity: 60-90 days
• Sowing method: Sow indoors

Di Ciccio

• Di Ciccio is a very productive Italian heirloom that produces tightly packed 3-4in (5-7cm), blue green flower heads on strong short stems. After cutting the main head, more side shoots develop, producing many more small to medium-sized heads through the summer.
• Sun: Full sun
• Spread: 12 inches
• Height: 24-30 inches
• Days to maturity: 50-85 days
• Sowing method: Sow indoors

Soil

• Although broccoli fairs well in a variety of soils, it does best in a medium-textured soil containing plenty of well-rotted organic matter, good drainage, and excellent water-holding capacity.
• Dig in some well-rotted manure or compost during the autumn or winter before planting. This will ensure the soil is rich and fertile.
• Broccoli grows best in slightly acidic soil with a pH of 6.0-6.5. Optimal soil pH will assist in the transfer of important nutrients and micronutrients.

Planting

• Start spring seedlings in seed trays or modules indoors about two months before the last spring frost. Harden off for two weeks in a cold frame. Set out hardened-off transplants to a well-prepared bed containing plenty of organic matter a month before the last spring frost.
• Sow fall broccoli directly into the soil about 90 days before the first fall frosts. Plant out in rows 24 in (60cm) apart with 30in (75cm) between the rows.

Aftercare

• Water regularly, particularly during dry periods, to ensure healthy growth throughout the growing season. Avoid watering broccoli heads directly as this can cause fungal rot.
• Place mulch such as straw or garden compost between rows of broccoli. This will help the soil retain its moisture as well as assist in keeping weeds under control.
• Check plants routinely to ensure insect problems are not getting out of hand.
• Add a side-dressing consisting of either well-rotted manure or fish meal around the base of the plant’s main stem once its central head has been harvested.

Harvesting and storing

• Harvest broccoli heads when they have reached maximum size but before flower buds turn yellow. If the yellow flowers begin to open the plant will stop producing more heads and the broccoli will taste bitter and unpleasant.
• Use a sharp knife, taking off about 10cm of the main stem. Cut stems at an angle to prevent water from collecting in the stem and causing rot. Doing this regularly encourages new side-shoots to develop.
• Eat broccoli heads shortly after cutting. After harvest, the heads deteriorate quickly and can rapidly develop moulds. If you don’t intend to consume immediately, keep the heads dry and store in a vented plastic bag within the crisper section of the refrigerator. Consume within 1-2 days.

Pests and diseases

• Cabbageworms and cabbage loopers are the two primary pests you need to watch out for. The larvae feed on the leaves, and can go through the plant quickly. Remove caterpillars by hand, or spray Bacillus thuringiensis (Bt) to control them.
• Cabbage maggots attack broccoli roots. Place row covers over the plants to prevent the flies from laying eggs at the base of the plant.
• If water is allowed to pool between the individual flower buds on a broccoli head it will rot. Avoid directly watering broccoli heads.