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

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17 Aug 20, ashley shepherd (New Zealand - temperate climate)
my seedlings keep getting ruined, they start to grow then fall over/out with no roots left. I dug around and looks like grass grubs in my beds how do I rid my garden bed of these?
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20 Feb 21, Jay (New Zealand - cool/mountain climate)
Perhaps they are still too small - transplant shock ? try letting them grow larger maybe and soak the furrow first not the plant after till established.
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19 Aug 20, Anonymous (New Zealand - temperate climate)
Ring an agricultural supply company and ask to talk to an agronomists. Would probably be some grub or worm in the soil. I have never had the problem in 40 years.
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20 Apr 20, Greg Cave (New Zealand - temperate climate)
Is it advisable to fold leaves over the broccoli head as you do with cauliflower? The heads are still quite small but parts seem to be yellowing.
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21 Apr 20, (New Zealand - sub-tropical climate)
Putting the leaves over the broccoli head won't achieve anything. It is natural with caulies. If the heads are not growing and turning yellow and you have small plants then I would say you didn't fertilise them enough. The heads should fully develop in about 7-10 days.
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03 Dec 17, carol (New Zealand - temperate climate)
growing broccoli do you cut any outer leaves?pls
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02 Jan 17, Tania hodges (New Zealand - cool/mountain climate)
Why does our plants only produce really small main heads of broccoli, the plants appear to be really healthy.
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03 Jan 17, John (Australia - temperate climate)
It may be a small headed variety. Many of the large headed varieties are only available from commercial seed growers Contact Egmont Seeds (NZ) they have larger headed varieties.
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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.
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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.
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Showing 1 - 10 of 18 comments
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I live in Hervey Bay. I have planted Broccoli seeds. They never form a head for me to harvest. They are just leaves. How can I get them to grow the edible broccoli head?

- Kathleen Foxwell

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