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

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.
11 Oct 19, Patty Kipps (USA - Zone 7a climate)
Does it get cold enough for long enough where you are? Broccoli needs cool weather.
12 Aug 19, Roland (USA - Zone 9b climate)
Patricia, I experienced the same last year in zone 9b. Not a single head or side shoots. After six months I pulled the plants and put them in the compost. Nothing goes to waste in my garden.
21 Aug 12, Deanna (USA - Zone 9b climate)
I have fabulous success with broccoli year after year. I have a couple of tips that help prevent/delay bolting and a question. Tips: Keep broccoli moist. Never let it dry, especially during warmer weather. To retain moisture and drastically reduce weeds, use a heavy mulch. I use hay and I add a layer as soon as the bottom layer starts to break down. One bale of hay will mulch about 100' sq and costs about five bucks. I grow my broccoli with collards, cauliflower, cabbage, carrots and onions during the cooler weather and with whatever survives, pops up or I get around to planting (cause we have 5 growing seasons here). Now the question: Although I can grow broccoli that's so green it's blue, is 4' tall and 6' around and produces side shoots for three months...my husband HATES the variety! I'm aware of the difference in the flavor of this particular variety (Waltham 29). It has an extremely dense taste, similar to asparagus, which I love, but Eddie refuses to eat it so it's pointless to grow it! Any suggestions on a heading variety (heat tolerant) that's more like the market variety? I collect my seed, so I try to find heirlooms, open pollenated.
24 May 21, Deniza (USA - Zone 9b climate)
Hello Deanna, I am going to start gardening for the first time this year in zone 9B. I am looking at August as the time I can get anything in the soil. Would you be willing to mentor me? If so, please reply to this post. Thank you for considering my request.
10 Mar 14, GJX (USA - Zone 5a climate)
Deanna, 9b should be toward California. Try these: Hybrids such as Italian green type also called green sprouting broccoli or calabrese These types take from 75 to 140 days to grow once in the ground too the table.
08 May 12, Linda (USA - Zone 7a climate)
Hi I live in new jersey. I cant seem to grow Broccoli. I tried two years and no good. The plants goes to seed every time. Please if you can write me back. I really dont know whats going on. Thank you Linda
10 Mar 14, GJX (USA - Zone 5a climate)
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. This cool-season crop grows best when daytime temperatures are in the 60s F. Grow in both spring and fall, but avoid mid-summer crops as hot weather can cause premature bolting.
09 Feb 12, Lee-Ann Connolly (USA - Zone 8a climate)
Hello When you say PLANT in garden is that the seed to plant in the garden where they going to grow or seedlings ? Many Thanks Lee-Ann
Showing 11 - 20 of 23 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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