Garden Preparation for Planting Broccoli
Broccoli is a heavy feeder, and performs best with a deep root zone in soil with ample organic matter.
When growing Broccoli, prepare the soil to a depth of 12-20” (30-51cm). Lay down a 2-3” (5-8 cm) layer of good garden compost or composted manure when you prepare the soil.
Broccoli and other cruciferous vegetables grow best in soil with a slightly acidic to slightly alkaline pH, pH 6.8-7.4. See Changing Soil pH for tips on adjusting soil pH.
If your soil is lean or you’re short on compost, you can amend the soil with a good organic fertilizer and mix it into the soil before planting.
Broccoli also benefits from supplemental calcium in the soil.
Planting Broccoli
Broccoli seedlings should have succulent stems and large, green leaves. Seedlings with hard stems or purplish, stunted leaves have been too long in small pots and will produce tiny broccoli heads.
In fertile soil, broccoli plants can spread 2-3’ across, by 2’ high.
If you’re growing broccoli in a single-dug bed (soil prepared to a depth of 10”—25 cm), set plants out 15-18” (38-46 cm) apart, in rows 18-24” (46-61 cm) apart.
If you’re growing broccoli in a raised garden or double-dug bed (soil prepared to a depth of 18-24”—46-61 cm), set plants out 18-20” (46-51 cm) apart, in rows 18-24” (46-61 cm) apart.
With most vegetables, deep soil preparation allows you to tighten spacing between plants, but with broccoli and other cruciferous vegetables, the plants grow larger and need a little more space when planted in a deep, fertile soil.
Harvesting and storage
when the florets at the outer edges of the broccoli head begin to loosen, then it is time to harvest the crop. The farmer should cut the broccoli stems at an angle to prevent water settling in the stem and occasioning rot. It is important for smart broccoli farmers to understand that the vegetable has a relatively short shelf-life. It is therefore important to get it to the market (especially if you are handling the transport logistics) as soon as possible.
Things to note:
Too much nitrogen encourages leaf growth hence delaying the heads from setting
Weeding may disturb broccoli roots so its recommended that farmers mulch their crops to control weeds
Some side shoots may grow from the main stem where the head has been cut off hence providing several harvests to a farmer
Hot temperatures may become a hindrance to good head formation
Hot temperatures may also lead to immature flowering –i.e. broccoli plant forms a flower stalk before forming a compact head.
Broccoli Diseases
Bacterial Soft Rot is the only common broccoli disease I’ve encountered. Sections of the head darken, go soft, and begin to collapse.
The disease is more common under warm, wet conditions, and with broccoli varieties that have flat heads. Varieties with dome-shaped heads (e.g., ‘Arcadia’, ‘Marathon’, and ‘Shogun’) are more resistant.
Other broccoli diseases common to large-scale field production include Black Rot, Club Root, and Fusarium Yellows.
Most broccoli diseases enter plants through injured tissues, so garden practices that limit injuries to plants and organic pest control measures that reduce damage by chewing insects can go a long way toward preventing the spread of diseases.