Growing Broccoli is very easy and provides great satisfaction, even in a home garden. It is a Mediterranean plant, and its cultivation is widespread, especially in Central and Southern Italy, where several local varieties exist.
These Broccoli goes by many common names such as “Calabrese broccoli”, “Nero di Napoli”, “Veronese broccoli” and more. It is typically consumed mainly in autumn and winter and is cultivated (for early harvests) starting from the summer months.
Let’s explore all the necessary techniques and tips for cultivating broccoli in the home garden and enjoying healthy and tasty plants.
What are Broccoli
Broccoli (Brassica oleracea var. italica) belongs to the botanical family Cruciferae or Brassicaceae. It is a close relative of cauliflower.
The main difference between cauliflower and broccoli lies in the inflorescence, which is white and compact in the former, and green and more frilly in the latter.
Broccoli plants have vigorous vegetative growth. They have a fibrous root system that does not reach great depths. The stem is erect and can reach over 50 cm at full maturity. The leaves are evenly distributed on the stem, ribbed, dark green with large white veins. They become larger towards the lower part and narrower as you move upward on the stem.
The edible part consists of the inflorescences, which are branching buds that terminate with a large green head. The broccoletti, highly appreciated in typical Southern Italian cuisine, are nothing but the buds of these inflorescences. For this reason, they need to be harvested well before they open for flowering. The broccoli stem end is also consumed and is very fleshy.
Another peculiarity of broccoli is that after cutting the main head, new side shoots, equally tasty, emerge. This way, the plant extends the harvest period and increases the yield.
However, not all varieties possess this characteristic. Let’s see the distinctions within the large family of broccoli.
Varieties of Broccoli
The cultivation of broccoli is part of the peasant tradition of Central and Southern Italy.
Many are the typical local varieties that are unfortunately being lost, replaced by hybrid seeds from multinational companies.
With hybrid seeds, the variety difference is mainly in the duration of the production cycle. We have early varieties (50-60 days), mid-season (75-80-90 days), and late varieties (100-120 days). The indication of days refers to the period between the transplanting of a well-formed young plant and the harvest.
Early and mid-season varieties produce a central inflorescence of good size, and then many side shoots. Late varieties, on the other hand, produce a single large head, and after its harvest, no new side shoots are produced.
Among the classic varieties, Calabrese broccoli is the most early, while Veronese broccoli is one of the latest. Broccoli, on the other hand, has a mid-range harvest time. Its particular characteristic that has made it famous worldwide lies in the unique shape of its inflorescences, which resemble a spiral pyramid.
Sowing and Transplanting Period of Broccoli
The cultivation of broccoli usually begins in the summer, especially in northern regions. The sowing takes place in June, July, and August, while staggered transplanting can occur from July to September.
From the sowing in the seedbed (in polystyrene seed trays), it takes about 30 days to obtain ready-to-transplant seedlings. Therefore, if you decide to start from seeds, carefully calculate your timing.
Frequently, however, ready-to-transplant seedlings are purchased from a nursery. To better understand the timing, it is good to consider some practical examples:
- If you transplant an early variety in early August (60 days), you will start harvesting around the end of September.
- If you transplant a mid-season variety in September (75 days), you will have to wait until November for the harvest.
In the regions of Central and Southern Italy, transplanting can also be done at the beginning of October for later harvests toward the end of the winter season.
An excellent idea is to perform staggered transplanting, ensuring a continuous harvest over time.
In general, early varieties are less tolerant to freezing temperatures, so it is best to start cultivation no later than the end of August.
Soil and Fertilization
Broccoli prefers a medium-textured, loose soil enriched with organic matter. What it dislikes is waterlogging, so before starting cultivation, good soil preparation is essential.
As for fertilization, it is not necessary before transplanting. As it is a vegetable grown successively after a summer crop, you can take advantage of the fertile soil where an abundant organic fertilization was applied in spring-summer. For example, in a field previously cultivated with zucchini or tomatoes and fertilized with mature manure, compost, or worm humus.
Broccoli is a plant with a considerable vegetative growth. Therefore, it is necessary to respect the appropriate distances to have lush plants.
Optimizing the space as much as possible, these are the guidelines for planting:
- Early and mid-season varieties: 40 cm within the row, 50-60 cm between rows.
- Late varieties: 60 cm within the row, 80 cm between rows.
When it comes to irrigation for growing broccoli, different needs apply. If you start cultivation in summer and experience significant drought, you need to use an irrigation system. This way, you ensure a constant water supply to the plants, at least until autumn rains arrive.
If you start cultivating later and are lucky not to encounter a prolonged dry period, normal rainfall should be sufficient to meet the water needs of the plants. Therefore, consider whether to set up an irrigation system or not, based on previous cultivation experiences in previous years.
Cultural Care for Broccoli
As we have seen for cauliflower, earthing up the plants is of fundamental importance.
This operation consists of manually mounding soil around the base of the plant. It allows Broccoli to thicken its stem and roots and better resist adverse weather conditions such as heavy rain and strong wind. During earthing up, another agronomic operation called hoeing is also performed. It involves removing weed growth. This operation does not require natural mulching. Earthing up can be done one month after transplanting and then every 20 days until the time of harvest.
To achieve great satisfaction with broccoli, careful attention must be given during harvesting. It is crucial to harvest at the right time. Usually, it is done when the broccoli heads are well-formed, still firm, and compact. They should have a beautiful intense green color, and you should proceed before the flower buds start to open. The harvesting process is simple: you cut the inflorescences at the base, making sure to include part of the stem along with the heads, including all the branches and their corresponding leaves. However, be careful not to cut too low, as this could prevent new side shoots from developing. Another tip is to make a transversal cut on the stem during harvesting. This way, in case of rain, water will flow away easily, avoiding stress and rot on the plant.
Biological Defense of Broccoli
Among the pests affecting broccoli, the most formidable is certainly the cabbage worm, especially in its larval stage. To eliminate this pest, consider the following two techniques:
- The first involves using a natural macerate of tomato leaves and females. This is applied to the larvae and literally fries them, making it highly effective.
- The second solution is using Bacillus thuringiensis var. Kurstaki. It is a highly effective biological product that should be applied in the evening. Unlike the macerate (which you can make at home), you can easily find Bacillus thuringiensis in stores (available here).
Other pests that feed on broccoli leaves are slugs. You can eliminate them by placing traps with beer in the area where the plants are grown (use an inexpensive brand).
Among the fungal diseases that affect broccoli cultivation, we mention alternaria brassicae. This can be prevented in organic agriculture by using a copper-based product 20 days after transplanting (like this one).
Uses of Broccoli
Black broccoli is an ideal vegetable to consume in autumn and winter. It is rich in nutritional properties and can be prepared in various delicious recipes. For this reason, we will dedicate a special in-depth article to its properties and recipes. In the meantime, we wish you successful organic cultivation and happy gardening, as the garden never takes a vacation—remember that!
- Harvard University: “Vegetable of the month: Broccoli” – This resource discusses the nutritional benefits of broccoli, which is high in vitamin A and folate (vitamin B9), as well as vitamins C and K. It’s also a good source of potassium.
- University of Arkansas: “Broccoli-a Nutrient Dense Food” – This resource discusses the anti-cancer properties of broccoli, which is rich in nutrients including vitamins A and C, fiber, folic acid, calcium, and potassium.
- Pennsylvania State University: “Broccoli consumption protects gut lining, reduces disease” – This resource discusses the health benefits of broccoli, particularly its role in protecting the gut lining and reducing disease.