Green gardening: planting and growing broccoli

Broccoli belongs to a large and varied genus, Brassica, that includes Brussels sprouts, cabbage, and cauliflower, and that has the ability to grow in cool weather. Here's a guide to growing your own:

Not only is broccoli extremely hardy in cold weather but it requires a long, cool season for growth. It will be one of the earliest vegetables you plant in the garden each year, and it will produce its delicate flower heads in late spring and early summer.

• Start broccoli indoors at least four weeks before the time to set out the seedlings — which you should calculate as two weeks before the date of the last expected frost.
• If you have a short growing season, six weeks will give you larger plants to set out. Sow the seed one centimetre (half an inch) deep in flats, sprinkle a thin layer of sterile sphagnum moss or vermiculite on top, and water well.
• Keep the flats in a dark, cool place until the seeds sprout, or cover them with newspaper.
• Good early varieties of broccoli include: 'Green Comet', 'Premium Crop', and 'Packman'. 'Arcadia' is recommended for fall crops.

The seedlings should stand about one to two centimetres (half to one inch) apart.

• When the plants are about four centimetres (two inches) tall, transplant them into individual pots or into flats where they will have more room.
• Keep the seedlings in a sunny but cool place in your house; they will not grow well in warm temperatures.
•  At least two weeks before it is time to set out the seedlings (earlier if the weather is not too cold), place them in a cold frame or in a sunny, sheltered spot outdoors, to harden them off.
•  Never plant broccoli where Brassica members were grown the year before.

Prepare the soil about two weeks before transplanting time by working in a five-centimetre (two-inch) layer of compost or three centimetres (one inch) of well-rotted manure.

• Lime the soil now if it is strongly acid and if you did not lime it the previous fall.
• About two weeks before the last expected frost, set out your hardened seedlings.
• Place them 45 to 60 centimetres (18 to 25 inches) apart in rows 90 centimetres (35 inches) apart.

To raise a good broccoli crop, you need abundant water and rich soil.

• Ensure moist soil with a thick mulch and deep, slow waterings during dry periods.
• At least once during the growing season, pull aside the mulch and apply 250 grams (one cup) of a balanced organic fertilizer or 250 grams (one cup) of fish meal or alfalfa meal along every three metres (10 feet) of row.
• Replace the mulch, and water to soak the fertilizer into the soil.

Protect the plants against cutworms by surrounding them with paper collars, which you can make by cutting the bottoms out of paper cups.

• Push each collar three centimetres (one inch) into the soil. Water well, and mulch the soil thoroughly.
• Clubroot, the most serious disease of broccoli, is best avoided by crop rotation. Weak, yellow plants with malformed roots indicate this disease. To combat it, raise the soil pH to at least 6.8 by adding ground limestone.
• Destroy infected plants and do not plant members of the cabbage family in that location for several years.
• Flea beetles, small black insects that hop away when disturbed, make small, pale spots on the leaves and can kill young plants. Cover with a floating row cover or spray them with kaolin clay.
• If cabbage worms attack, apply Bacillus thuringiensis. 

Now you know how to plant and grow your own broccoli. Not only is it loaded with vitamins, fresh broccoli tastes delicious. Save yourself some money and grow your own vegetables in your backyard!