Here’s a quick and handy guide to growing broccoli in your backyard garden – planting to harvest…
Broccoli is generally a very easy crop to grow – provided you live in a suitable climate. Broccoli is a cool-season crop that does best in cool and temperate climates such as USDA zone 3-6. If you have a warmer climate, try it by all means, but you may have mixed results. If you do live in a warmer area, the best time to grow broccoli is probably going to be in the fall, as long as you have enough time before your first hard freeze for your broccoli to head up.
Broccoli generally comes in two main varieties. The popular kind with large green heads is called calabrese. This is the type that we will consider when we look at growing broccoli in this article. The other kind, which has smaller purple or white heads, takes much longer to grow and must be planted in late spring for harvest the following spring.
Planting Broccoli (Calabrese)
Broccoli plants can grow up to 3 feet tall, so choose a site for growing broccoli plants where they will not invade or shade other plants. They will like some sun but they do not need to be in full sun all day. 6 hours per day should be sufficient, especially in warmer areas.
Crop rotation is very important to avoid disease, and you should leave 3 clear seasons before growing broccoli or another crop of the brassica family (broccoli, cabbage, cauliflower) again in the same spot.
You can plant broccoli seeds directly in the garden around 4-6 weeks before the usual last frost date. In cold climates, cover the area with cloches for 2 weeks before planting, as well as after – or start your seeds indoors and transplant outdoors 2 weeks before the last frost date, covering with row cover until the danger of frost has passed. If you are in a warmer climate, you can direct seed in the garden around March.
When the seedlings appear, thin them to 9-12 inches apart, depending on the variety. (Your seed packet should tell you how far apart your particular variety should be planted.)
Growing & Harvesting Broccoli
Once the seedlings are thinned and established, you can add compost to the surrounding soil from time to time, keeping the compost 3-4″ away from the stem of the plant.
Weed around the growing broccoli plants frequently or cover the soil with a weed deterrent mulch. As they grow, broccoli will usually shade out most weeds, but a thick cover of mulch is usually helpful when they are small.
Like all of the brassica family, broccoli can be attacked by pests including aphids, caterpillars, mildew, clubroot, and cabbage root fly. If you identify any of these on your plants, take action immediately. Some can be treated with products from the nursery, others are more serious and you must dig out the plants and get them out of your garden. Caterpillars can be picked off and squished, or for a heavy infestation, you can spray with an organic spray containing Bt. Keeping the plants covered with netting as long as possible will also help greatly with cabbage moths and caterpillars.
Harvest when the flowers are budding and green, before they turn yellow or open. You can either snap or cut the stalks.
If you have a large crop you may want to freeze some. Broccoli freezes well. Cut the head into spears and blanch them by boiling for 2-3 minutes in salted water. Let them cool for 5-10 minutes, patting them dry with absorbent paper, and freeze right away. Freezing is a great way to make the most of a large broccoli harvest.