Growing Broccoli

Brassica sp. : Brassicaceae / the mustard or cabbage family

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

(Best months for growing Broccoli in USA - Zone 5a regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • P = Sow seed
  • 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

Your comments and tips

23 Apr 20, Michael (Australia - temperate climate)
Is late April to late to seed broccoli in Adelaide?
25 Apr 20, Steve (Australia - temperate climate)
Yes it is to late now, plant out seedlings if you can get hold of them.
24 Apr 20, Anon (Australia - temperate climate)
It takes about 4 weeks to grow a seed to seedling stage to transplant. And it is time consuming - watering 2-3 times a day. Miss a day or so and the seedlings could be dead. Plant seeds now and it takes about 12-16 weeks to grow to pick. You are looking at July Aug for harvest. I live sub tropical and most vegies do not grow much in July Aug. You are temperate so they will grow less probably. SO you plant SEEDLING this time of the year. A general rule sub tropical and probably temperate (no frosts) is for winter veg you plant late summer and for summer veg you plant late winter/very early spring. I will be picking my first broccoli next week.
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.
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.
15 Sep 19, Kathleen Foxwell (Australia - tropical climate)
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?
16 Sep 19, Anon (Australia - sub-tropical climate)
Broccoli is best grow in your/my area, autumn into the winter - plant seedlings or seeds early March to May. DO NOT have super rich soil. SOIL high in N will just produce a lot of leaf. I had this problem last year with cabbage and broccoli coming out of winter into spring. I won't do that again. I have tried seeds the last 2 years. For broccoli I think the best is to just buy seedlings from Bunnings.
14 Jun 19, Patricia Foster (USA - Zone 9b climate)
Here in central Florida, we grew enormous broccoli plants but they never produced anything, even after six months growing. We put the seedlings in the ground in October in a marl soil that retains moisture and also used plenty of compost and some 10-10-10. Any ideas what went wrong or what we should do to amend the soil?
24 Jul 20, colleen (USA - Zone 10b climate)
This has happened to me a couple of times in the South too, with various cole crops. Have you grown this variety of broccoli in this location and at the same time of year before, with success? The reason I ask is, some brassicas require vernalization (a sufficient number of cold temperatures before they flower/head) and some types may be photoperiod sensitive (waiting for days to get short enough/long enough to trigger flowering/heading). Did you have an especially warm winter? Definitely make sure you're growing a variety that's best suited to your latitude, and are growing it at the suggested time of year. I hope you at least got to eat your plants! The leaves are a delicious consolation prize. Also! Important tip: always leave broccoli roots in the ground when you harvest the plants. Decaying broccoli roots are toxic to verticillium dahliae, a stubborn soilborne fungus. Broccoli is worth growing for that reason alone!
26 Nov 19, anon (USA - Zone 9b climate)
- It sounds as though you have over fertilised them with far too much NITROGEN. N produces growth - leaves. Also grow them into the cooler winter months. DO NOT grow them into the hot summer months.
Showing 41 - 50 of 313 comments

My broccoli have gone from juvenile heads to spreading out and flowering in a week. What have I done wrong?

- josie

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