Broccoli is a popular and easy-to-grow winter crop here in Florida. Plus, it’s incredibly nutritious, providing good amounts of riboflavin, calcium, iron, and vitamins A and C.
You may be aware that broccoli is a member of the cruciferous family of vegetables along with kale, cabbage, cauliflower, kohlrabi, and Brussels sprouts. What you may not know is that these vegetables are all actually members of the same species—you read that right, species. Brassica oleracea includes broccoli as well as those vegetables previously mentioned.
Thousands of years of human cultivation and selective breeding has resulted in changes to the wild Brassica oleracea that have given us the vegetables we know and love today. Native to the Mediterrean, the original wild plant was grown for its foliage; the choice plants were those that grew larger leaves. Over time, through saving seeds and continuing to grow those plants with the largest leaves, the vegetable we know now as kale came onto the scene by the fifth century B.C. Botanically, kale is Brassica oleracea var. acephala which means "cabbage of the vegetable garden without a head." Continued selective breeding went on to result in cabbage (Brassica oleracea var. capita) and kohlrabi (Brassica oleracea var. caulorapa).
It has only been in the past thousand years that people began selecting plants for their immature flower buds. This selection resulted in the introduction of cauliflower (Brassica oleracea var. botrytis) by the fifteenth century and finally broccoli (Brassica oleracea var. italica) in the sixteenth century. Broccoli received the variety name italica because it was developed in Italy. Finally, the eighteenth century would bring about the selection of Brussels sprouts (Brassica oleracea var. gemmifera).
It is amazing to think that selective breeding can result in such unique vegetables of the same genus and species!
Planting and Care
Broccoli needs cool weather to thrive, so here in Florida it should be planted during fall and winter. It takes 80-100 days to mature, so don't plant too late in the season—rising temperatures may cause the plants to "bolt," meaning the flowers within the head will start to open.
In South Florida, broccoli transplants can be planted in the garden from September through January. North and Central Florida gardeners can plant transplants anytime from mid-August through mid-March. You can buy transplants at a garden center or start your own from seed.
Like all plants, broccoli needs certain nutrients in order to grow, so fertilizing with a 6-8-8 fertilizer of nitrogen (N), phosphorous (P) and potassium (K) will help your plants succeed. You can use either a liquid fertilizer solution or a controlled-release solid fertilizer. You should fertilize at planting time and then regularly throughout the growing season. A layer of mulch can help retain moisture around the plants and suppress weed growth.
Although broccoli is a cool-season vegetable, it will still benefit from protection from low temperatures (32°F or cooler), especially when plants are young and tender.
Vegetables like broccoli need at least four to six hours of sun per day, so you'll need to find a sunny spot. Vegetables also need plenty of water, so be sure that you have a convenient source nearby. Provide one to two inches of water per week; heavy soakings once a week are preferred to several lighter sprinklings.
A number of broccoli varieties are available, with 'Waltham 29' being an old favorite. It can be harvested 80-100 days from when it is transplanted and will continue to produce side shoots after the main head is cut. Other good varieties for Florida include 'Early Green', 'Early Dividend', 'Green Sprouting'/'Calabrese', 'Packman', and 'De Cicco'.
It's also a good idea to have your soil tested through your local Extension office before you plant. Ideally, you're hoping for a soil that falls in the pH range of 6.2 to 6.5. Consider amending the soil with organic materials like composted manure before planting your broccoli.
For more information on growing broccoli, contact your county Extension office.