How To Grow Broccoli

Broccoli is a nutritious and versatile vegetable that can be enjoyed in a variety of dishes. A member of the Brassica family, it is closely related to other cruciferous vegetables such as cabbage, cauliflower, and kale.

Growing broccoli in your garden is an excellent way to ensure a steady supply of this nutrient-rich vegetable, and it can also be an enjoyable and rewarding experience.

Published: April 21, 2023.

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Required Growing Conditions

In order to thrive, broccoli demands specific growing conditions.

When it comes to soil, this vegetable prefers well-draining, fertile soil with a pH level between 6.0 and 6.8. Enriching the soil with organic matter, such as compost, well-rotted manure, worm castings, or similar, can provide the necessary nutrients for optimal growth. Also, adding a balanced fertilizer like 15-15-15 or similar, preferably with a gradual release of nutrients, provides the plants with proper growing conditions.

Note: Broccoli likes nitrogen, but to keep the plants strong and healthy, one should not add too much nitrogen.

Broccoli is also a sun-loving plant and requires at least six hours of direct sunlight per day. However, it can tolerate partial shade, especially in regions with hot summers.

As for water, maintaining consistent moisture is crucial. Broccoli needs about 1 to 1.5 inches of water per week, either from rainfall or supplemental irrigation. Overwatering can lead to root rot, while insufficient water can cause heads to become tough and bitter.

When To Sow And Transplant Broccoli

Timing is crucial when planting broccoli.

For spring harvests, seeds should be sown indoors approximately six to eight weeks before the last expected frost date.

Once seedlings have reached a height of 2 to 3 inches and have at least two sets of true leaves (This typically occurs two to three weeks before the last frost date.), they can be transplanted into individual pots and, over time, hardened off.

When the danger of the last frost is gone, transplant the seedlings.

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Note: When transplanting the seedlings into a permanent location, if the soil is heavy and has lousy drainage, feel free to add some more compost and a third of an ounce (~10g) of balanced NPK fertilizer and mix them thoroughly with the soil from the hole.

For fall harvests, seeds can be directly sown outdoors 85 to 100 days before the first expected fall frost.

Alternatively, transplants can be started indoors and moved outside in mid to late summer.

How Much Space Does Broccoli Need to Grow

Proper spacing is essential when growing broccoli, as it allows for adequate air circulation and prevents the spread of diseases.

Each broccoli plant should be spaced approximately 18 to 24 inches (~46 - 61 cm) apart, with rows spaced 24 to 36 inches (~61 - 91 cm) apart. This spacing permits the plants to develop sizeable heads and ensures that they receive the necessary nutrients from the soil. Additionally, wide spacing can help to reduce competition for water and sunlight, promoting overall plant health and a bountiful harvest.

But, actual distance also depends on the broccoli variety and available space.

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How Long Does Broccoli Take To Grow

The duration of broccoli growth depends on the specific variety and growing conditions. On average, broccoli takes between 70 and 100 days from transplanting to reach maturity.

Early varieties can mature in as few as 50 days, while late-season varieties may take up to 120 days.

It is essential to monitor the development of the broccoli heads and harvest them before the florets begin to separate and turn yellow, as this is an indication that the plant is beginning to flower.

Broccoli Companion Plants

Certain plants can be grown alongside broccoli to support its growth and deter pests.

Some beneficial companion plants include onions, garlic, and chives, which help to repel aphids and other insects. Additionally, planting marigolds and nasturtiums near broccoli can attract beneficial insects that prey on pests.

Leafy greens, such as lettuce and spinach, can also be grown with broccoli, as they share similar growing conditions and do not compete for nutrients.

Crop Rotation: Plants Before and After Broccoli

Crop rotation is an essential practice in maintaining soil fertility and preventing the buildup of pests and diseases.

When planning your garden, it is advisable to avoid planting broccoli in the same location where other members of the Brassica family, such as cabbage, cauliflower, or kale, have been grown in the past two to three years.

This helps to minimize the risk of soil-borne diseases and pests that could negatively impact your broccoli crop.

Instead, plant broccoli in an area where legumes, such as peas or beans, were previously grown. Legumes are known for their nitrogen-fixing capabilities, which can help improve soil fertility and provide an optimal environment for broccoli growth.

After harvesting your broccoli, you can plant a different crop, such as root vegetables like carrots, beets, or potatoes, which have different nutrient requirements and will not attract the same pests.

Incorporating cover crops, like clover or alfalfa, into your rotation plan can also contribute to a healthy garden ecosystem. These cover crops can be grown during the off-season and then tilled into the soil, providing organic matter and nutrients for the subsequent crops.

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Most Common Broccoli Pests

Broccoli is relatively easy to grow, but it is susceptible to certain pests and diseases, including:

  • Cabbage Worms: These green caterpillars, also known as cabbage loopers or imported cabbage worms, can cause significant damage to broccoli leaves and heads. They are the larvae of small white or yellow butterflies.
  • Aphids: These small, soft-bodied insects can be found in clusters on the undersides of leaves or on broccoli heads. They suck plant sap, leading to distorted growth and the potential spread of diseases.
  • Flea Beetles: These tiny, jumping beetles chew small holes in leaves, leading to a lace-like appearance. They can weaken young plants and reduce their overall vigor.
  • Cutworms: These caterpillars are active at night, feeding on stems at the soil level and cutting off young plants. They can be especially damaging during the seedling stage.
  • Slugs and Snails: These pests can cause damage to broccoli leaves and stems by leaving irregular holes and slimy trails. They are particularly problematic in damp and humid conditions.

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Most Common Broccoli Diseases

  • Clubroot: This soil-borne disease is caused by a fungus called Plasmodiophora brassicae. It leads to swollen and distorted roots, which can cause wilting and stunted growth. Infected plants may also exhibit yellowing leaves.
  • Blackleg: Caused by the fungus Phoma lingam, blackleg leads to dark, sunken spots on stems and leaves, which can eventually result in plant collapse. This disease is most problematic in wet conditions.
  • Downy Mildew: This fungal disease is characterized by a white, fluffy growth on the undersides of leaves. It can cause yellowing and distortion of leaves, and may lead to defoliation and reduced plant vigor.
  • Alternaria Leaf Spot: Another fungal disease, Alternaria leaf spot causes dark spots with concentric rings on leaves. Severe infections can lead to defoliation and reduced yields.

To prevent and manage these pests and diseases, practice good garden hygiene, implement crop rotation, and maintain proper spacing for air circulation.

Additionally, using floating row covers, introducing beneficial insects, and applying organic or chemical controls when necessary can help protect your broccoli plants from these common threats.


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Few Final Words

Growing broccoli can be a rewarding and enjoyable experience for both novice and experienced gardeners. By understanding the specific growing requirements of broccoli and implementing proper planting techniques, you can cultivate a healthy and bountiful crop.

Remember to provide the optimal soil, sun, and water conditions, as well as practice proper spacing and crop rotation.

With a bit of patience and attention, you will be able to enjoy the fruits of your labor – fresh, homegrown broccoli packed with nutrients and flavor.

For more information about growing broccoli, feel free to check the following: