Large-headed varieties produce the familiar domed heads that are composed of numerous clustered florets. Many large-headed varieties produce smaller side shoots after the primary head is harvested.
If the transplants site is exposed to cold below 40 degrees for a week or two, the chilling injury triggers heads to form way too early. Another good reason to heavily mulch broccoli.
If the growing tip of the broccoli is injured via rough handling, insects, or weather, a head may not form-Often called broccoli blindness.
If temperatures get above 27 C pick all of your broccoli quickly as the heads will rapidly start to bold at this point.
GROWING REQUIREMENTS OF BROCCOLI
Broccoli prefers a neutral pH – 6.5 to 7.5 preferred, down to 6.0 okay – Add some garden lime or crushed oyster shells to boost pH if your soil is acidic.
Soil temperature should be 16-18C
Broccoli Requires Rich Soil! Broccoli loves rich soil, they’re one of the hungriest plants in your garden, especially nitrogen
Space Plants At Least 40 cm Apart – We stagger our broccoli when planting, The first row would be 0 cm, 30 cm, 60 cm, 90 cm, and so on. The second row, 30 cm from the first row would be at 15 cm, 45 cm, 75 cm, 105 cm, and so on. This gives each plant the most amount of space, water, fertilizer to grow to their full potential.
Sow between rows and plants This is especially helpful when plants are small calendula and alyssum help with some pest control. Strongly scented herbs such as dill may deter cabbage butterflies, reducing the incidence of green cabbage worms on your broccoli.
Full sun is preferred for best yield, although the plants will tolerate partial shade when the temperatures rise.
Good Companion Plants for Broccoli: Bush bean, beet, carrot, celery, chard, cucumber, dill*, lettuce, mint*, nasturtium, onion family*, oregano, potato, rosemary, sage, spinach, tomato
Bad Companion Plants for Broccoli: Pole and snap beans, strawberry
Rainwater is the best option: Make sure your broccoli gets at least 3 cm water per week, 5 cm is better.
Mulch your broccoli well: 5-8 cm of mulch will be worthwhile, grass clippings, ground leaves, chopped straw all help keep the soil cool. If soil is too warm the broccoli will bolt.
If you notice: The first signs of boron deficiency in plants shows in the new growth. Leaves will yellow and growing tips will wither.
Add some Baron: Boric acid is another name for the common household cleaner Borax, which you may be able to find in the laundry aisle. Use 60 ml (1/4 cup) in 8 litres (2 gallons) of water. If you suspect a boron deficiency problem with your plants, a dose of boric acid used as a foliar spray will do the job. Be careful as you use boron on plants.
Pick the right variety of Broccoli-We only grow a few types of Broccoli for a reason, other varieties we have tried but they do not do well in our climate, soil type.
Cabbage Moths (Butterfly) and small green worms (cabbage worms). The companion plants do help significantly but they are not 100% foolproof.
The only sure way to keep cabbage worms off your plants is to isolate the plants under a floating row cover or mesh cages that surround the broccoli plants. If you have too much wind for row covers you can purchase or custom build broccoli cages covered in window screening or similar cloth cover.
Cabbage moths seem to be more attracted to plants when drought or poor soil conditions exist if they become a problem spray plants with BT (Bacillus thuringiensis (Bt) is a natural occurring, soil-borne bacteria that has been used since the 1950s for natural insect control.) and is much more effective when the moths are young.
Another good idea is to add a birdbath and perch close to your Broccoli and other brassica plants. Beneficial wasps will devour cabbage moths as well. If there are only a couple of cabbage moths in the area, we often use a butterfly net to catch and discard them.
To get rid of any cabbage worms out of your broccoli is to fill the sink with hot water and a handful of salt and a couple of tablespoons of vinegar. Leave for 20 minutes and vigorously swish the florets around to dislodge any unwelcome guests. The amounts have not been measured-it would depend on the size of the sink and the amount of broccoli you are washing. The majority of the cabbage worms will dislodge from the broccoli and sink to the bottom of your tub or sink.