Broccoli is an extremely valuable vegetable when it comes to providing a full range of vitamins and minerals (not to mention fibre) to our diets. This is a healthy plant and it is no wonder that mothers have been saying for years, “Eat your broccoli!”
When to Plant
Early crops should be sown indoors approximately 6-8 weeks before you want to plant them outdoors.
The seeds are easily germinated so do not crowd them in the seedling tray.
Give them at least 1.5 cm (one-half inch) from any other seed.
When the seedling has four true leaves (leaves that develop after the first two seedling leaves) transplant it into a larger container for growing-on.
Full sunlight, a regular feeding at half strength and a temperature of 16C (62F) will produce a nice short, thick plant for putting into your garden.
Late crops can be sown directly into the garden from early May until the first week of June in zone 3-5 gardens and as late as July in warmer areas.
Sow the seed as thinly as possible – 4 to 5 seeds per 30 cm (12-inches).
Remember that this seed germinates quite easily. Then thin out or transplant the resulting seedlings so they are 45 cm (18-inches) apart.
Generally, broccoli will mature approximately 100 days from the day you sow it.
Where to Plant
In full sun in good garden soil.
How to Plant
The transplants should be put into the garden 45 cm (18-inches) apart and the rows 75-80 cm (30 to 36-inches) apart. Try to put the plant at the same depth in the soil as it was in the pot. A trifle deeper is better than shallow.
Care & Maintenance
Harvest broccoli when the large central heads are still tight-budded. While you can eat them when the buds begin to swell and open, they are much nicer harvested tight.
Get A Second Crop
- Do NOT pull up the plant but simply cut off the top head.
- The side shoots will develop and you’ll get a ton of these from each plant.
- Harvest side shoots regularly before they start to stretch or the buds open on them.
- These smaller heads are easy to pick and use fresh in salads and stir-fries.
- The major pest of this plant is the green caterpillar of the cabbage moth.
Dust with rotenone or hand
Dropping the harvested heads in salty water will also help to identify the “surprises” you miss. Chewed up leaves are the primary sign that you have an infestation.
Preventing the Cabbage Moth Butterfly Caterpillar
If you are concerned with cutworms (small worms that eat the stems below the soil line) you can wrap the stem with a band of waxed paper or heavy paper to stop the worm from getting to the stem. A bit of lime or wood ash (a very tiny bit) scattered around the plant will deter slugs. Alternately, you can use an organic slug bait around your transplants.
A Research Moment…
Add MicroAmounts Of Sugar To Broccoli Irrigation Water To…
Here’s something worth messing about with. Turns out that “micro-amounts” of sugar added to broccoli irrigation water actually increase the levels of the health-promoting chemicals in the plant. (these are the anti-oxidants etc broccoli is famous for)
The tricky part for home gardeners is the amounts are so small as to be almost
So I’m thinking a very small “pinch” of sugar in a watering can full of water (I said it was small – around 85 millimolar) would be somewhere in the ballpark Here’s the Wikipedia definition of a molar in case you’re interested (it’s really small)
And if you’re into chemistry and want to translate all this into measurements we can use – I’m sure we’d all appreciate it. I confess this is somewhat beyond my math paygrade.
But from a practical point of view – it can’t hurt much. Just keep the amounts as small as you can.
And there’s no way short of your own lab that you’re going to know whether it works or not – or whether it works on other brassica plants.
But – it’s interesting nevertheless what we learn out there. 🙂
Reference: Rongfang Guo, Gaofeng Yuan, and Qiaomei Wang (Dept. of Horticulture, Zhejiang University, 268 Kaixuan Rd., Zhejiang, Hangzhou 310029, CHINA), “Effect of Sucrose and Mannitol on the Accumulation of Health-Promoting Compounds and the Activity of Metabolic Enzymes in Broccoli Sprouts,” Scientia Horticulturae 128(3), April 11, 2011,
(all numbers rounded out)
1/4 inch = .6 cm
1/2 inch = 1.3 cm
1 inch = 2.5 cm
6 inch = 15 cm
12 inch = 30 cn
18 inch = 45 cm
36 inch = 91 cm