Broccoli is a hardy vegetable that develops best during cool seasons of the year. Two crops per year (spring and fall) are possible in most parts of the country, especially with continuous improvement in fast maturity and heat tolerance that extends the life of broccoli through all but the hottest parts of the season. It belongs to the cole crop family (Brassica oleracea), which includes cabbage, Brussels sprouts, cauliflower, collards, kale, and kohlrabi.
Planting and Care
This fall crop of broccoli is well on its way to making heads.
A broccoli head begins a tiny bud at the center of the plant. It is especially important to prevent caterpillars and other insects from attacking the bud.Like most vegetables, broccoli needs at least 6 hours of sunlight daily. It grows well in reasonably fertile, well-drained, moist soils with plenty of added organic matter. Mulch will help keep the ground cool and moist. The soil pH should be between 6.0 and 7.0 for optimum growth and to discourage clubroot disease.
To be sure about your soil pH, get the soil tested. You can buy a kit or have a soil test done through your regional Cooperative Extension office. Apply fertilizer and lime using the results of the soil test as a guide.
In the absence of a soil test, incorporate plenty of nitrogen-rich amendments to the soil. These include blood meal, cottonseed meal, or composted manure. Or, you may apply a timed-release vegetable food such as 14-14-14 according to label directions. Work the fertilizer thoroughly into the soil before planting. A liquid starter fertilizer such as fish emulsion or 20-20-20 applied to the transplants at planting will help give them a good start. Dilute according to label directions.
Plant at the spacing stated on the Bonnie label. Generally, broccoli plants should be 18 inches apart. If planted in rows, space rows 24 inches apart to give yourself enough room to walk between them.
Plants need an even moisture supply to grow and produce good heads. An organic mulch of compost, finely ground leaves, or finely ground bark will help keep the soil cool and moist and suppress weed growth. You can also plant through black plastic in the spring to help warm the soil. Water regularly, applying 1 to 1.5 inches of water per week if rain doesn't cover it. You can measure the amount of water with a rain gauge left in the garden. If your soil is not naturally rich in nitrogen from abundant earthworms and regular additions of organic, nitrogen-rich amendments, then fertilize the plants again with a liquid fertilizer such as fish emulsion or 20-20-20 after they begin to develop new leaves.
Harvest and Storage
When you see a flower head beginning to form in the center of the plant, check its growth every day. Ideally, you harvest broccoli while the tiny buds are tightly closed. If the buds begin to swell or show yellow (the flower petals), cut the head from the stem right away, no matter how small it is, because the opening buds have a mealy texture. After cutting the main head, leave the plant to grow bite-sized side shoots in the axils of the leaves. Don't be disappointed if your broccoli head is smaller that those in the grocery store; they are usually grown in a friendly climate and with lots of pampering.
Heads keep for about a week in the fridge. Enjoy!
Troubleshooting
The best way to avoid problems is to keep your plants healthy and your garden clean. The main insect pests include cabbage loopers and imported cabbageworms, cabbage root maggots, aphids, and flea beetles. Disease problems include black leg, black rot, clubroot, and yellows. Contact your regional Cooperative Extension office for more information on pest identification and current control recommendations.