Growing Broccoli

Brassica sp. : Brassicaceae / the mustard or cabbage family

Jan F M A M J J A S O N Dec
  S               S    
    T               T T

(Best months for growing Broccoli in New Zealand - cool/mountain regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • Easy to grow. Grow in seed trays, and plant out in 4-6 weeks. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 45°F and 86°F. (Show °C/cm)
  • Space plants: 14 - 20 inches apart
  • Harvest in 10-16 weeks. Cut flowerhead off with a knife..
  • Compatible with (can grow beside): Dwarf (bush) beans, beets, celery, cucumber, onions, marigold, nasturtium, rhubarb, aromatic herbs (sage, dill, chamomile, oregano)
  • Avoid growing close to: Climbing (pole) beans, tomato, peppers (chilli, capsicum), eggplant (aubergine), strawberry, mustard
  • Nearly ready for harvest
  • Early stage
  • Side shoot regrowth after main head cut

Keep well-watered as seedlings. If left without water they will bolt to seed and be inedible. The plants should grow to develop plenty of large healthy leaves, then the green flowerheads follow, which are cut for eating. Leave the plant growing after cutting the main flowerhead, and get additional crops from the sideshoots which will develop.

Watch for cabbage white butterflies and remove the eggs and caterpillars as soon as possible.

There are two main types of broccoli. The purple sprouting is hardier. The heading varieties cope well with warmer weather.

Once a plant opens its yellow flowers then it is generally past eating as the flavour gets a bit overpowering and the plant gets very woody. Harvest them sooner rather than later.

'Broccolini' is a variety grown for the edible stalks. Grow fast with plenty of water and food, and pick as soon as possible.

Culinary hints - cooking and eating Broccoli

The stem (peeled), leaves, and flowerhead are all edible.

Steam for best flavour. Peel large stalks, slice and steam.
Goes well with blue cheese sauce.

Your comments and tips

16 Sep 08, Liz (New Zealand - temperate climate)
Alex, Cut it across the stem just above the first leaves. The plant will then send out side shoots.
16 Sep 08, Liz (New Zealand - temperate climate)
Jen, you will be able to collect seeds but if you have planted F1 hybrid seedlings they may not reproduce.
23 Sep 08, Ben (New Zealand - temperate climate)
I am new to planting broccoli and have recently cut the main head off one of the broccoli plants. I have several side shoots off the same plant, do they get as big as the main head?. The reason i ask is i dont want to leave them too long and let them go to flower.
27 Nov 08, Liz (New Zealand - temperate climate)
Peter, your broccoli seedlings should be fine. Broccoli usually do well when the plants produce plenty of leaf. They produce flower heads later in the growth cycle.
04 May 09, Dawn (New Zealand - temperate climate)
I was so excited to use the egg shells and get rid of the green catapillar. Now, welcome the grey aphid! After much research I have found that native Aust. ladybirds and lacewings do the trick. After even MORE research I've found where to buy them: (I cannot post a web link) bugs for bugs (dot com, dot au)
26 May 09, James (New Zealand - temperate climate)
Trish, your broccoli plants need their leaves to grow good size heads. So keep trimming to a minimum. Certainly, you can eat the leaves but you might find them a bit tough.
01 Aug 09, ian todd (New Zealand - temperate climate)
What's the best way to trim sprouting broccoli to keep the plant producing please?
30 Aug 09, Liz (New Zealand - temperate climate)
Iainie, you may be growing sprouting broccoli which will not produce a compact head but lots of loose ones. When the weather is hot and/or dry broccoli will flower quite quickly.
02 Jun 10, Liz (New Zealand - temperate climate)
Hi Les, I haven't heard of anyone getting sick, but the flavour is not so good when broccoli is about to flower. It is very strong and (to me) unpleasant.
03 Mar 14, Jacque Cubin (New Zealand - sub-tropical climate)
I am now 65 years old and don't remember broccoli being avaible when I was a chlid. In fact i'm thinking that i only became aware of it in the last 20 years or so. Can anyone answer my query please.
Showing 1 - 10 of 18 comments

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