Broccoli is a cool-weather, frost-hardy member of the brassica family grown for its edible flower buds and stalks. Although broccoli is packed with vitamins and minerals (vitamin A, potassium, folic acid, iron, & calcium to name a few), my family loves the taste and enjoys eating broccoli all season long. Learning how to grow broccoli is simple.
5 Tips for How to Grow Broccoli
1. Select a broccoli variety best-suited to your climate and tastebuds
- Imperial: Grows best in warm weather; growth slows down as temperatures cool.
- Green Magic: Tolerates warmer temperatures; small plant with smooth heads.
- Calabrese: Italian heirloom with a large head and many side shoots.
- Belstar: Heat-tolerant variety with many side shoots that grows well in mild-winter climates.
- Burgundy: Small main head with generous purple side shoots.
- Di Ciccio: Italian classic variety with many side shoots; freezes well.
- Marathon: Very cold-tolerant variety.
2. Plant broccoli at the right time
Broccoli is a sun-loving crop that needs cool weather to grow well. If it is too warm, the broccoli will bolt or not grow well. Additionally, broccoli grown during cool weather will have a sweeter flavor than its warmer weather counterpart. The ideal outdoor growing temperature for broccoli is between 65°F-70°F.
In cold winter areas, start seeds outdoors or plant broccoli transplants when soil temperatures are at least 40°F (2-3 weeks before last spring frost).
In mild winter climates, plant broccoli seeds 85-100 days before your expected fall frost.
Broccoli grows well in the cool of fall and winter here in the low desert of Arizona. In the low desert, plant broccoli seeds beginning in late August. Begin planting broccoli transplants in mid-September. Plant at 3-week intervals through January for a continual harvest until temperatures heat up in the spring.
3. Plant and care for broccoli correctly
- Although it likes cooler temperatures, broccoli needs at least 6 hours of sun. Choose an area that gets at least 6 hours of sun.
- Broccoli likes rich soil that is high in compost and organic matter.
- Plant seeds ¼- ½” deep and 3” apart. Thin to 12”-20” apart when seedlings are 2”-3” tall.
- Plant transplants 12”-20” apart and deeper than nursery pot level (transplants can be floppy). Firm the soil around the plants and water well.
- For square foot gardening, allow at least one square per plant. Close spacing typically means the main heads will be smaller, but the side shoots will be larger.
- As broccoli grows, provide consistent moisture and even watering. Don’t get the heads wet when watering. Mulching helps the soil retain moisture.
- Feed broccoli once a month during the growing season with a balanced organic fertilizer. Continue feeding after harvesting the main head to encourage larger side shoots.
- Use row covers and/or Bt to help prevent cabbage worms / cabbage loppers.
4. Harvest broccoli at the right time
Don’t wait too long to harvest broccoli. Harvest broccoli when the head appears full and tight, the tiny buds are closed, and before any yellow flowers appear. Harvest broccoli in the morning for the best flavor.
Using a sharp knife, cut the main stem at an angle 5”-8” below the head. (Cutting at an angle allows water to drain off rather than puddling on the stem.) In many varieties, side shoots will form after the main head is harvested.
5. Store harvested broccoli correctly
If cabbage worms are present, soak the broccoli head in cold salted water for 30 minutes before eating.
Unwashed broccoli will keep for about a week in the fridge. I love storing broccoli in these containers. Let washed broccoli dry thoroughly before storing.
Blanch and freeze broccoli to store it for up to a year.