Growing broccoli can be challenging because this cool-season vegetable requires just the right conditions: rich soil, consistent moisture, and extended cool weather in spring and fall (or during winter months in mild areas). The heads of homegrown broccoli are smaller than the broccoli sold at the supermarket, but they make up for size by being very tender.
Broccoli is a biennial plant with a two-year lifecycle (it will bloom in its second year), but it is treated like an annual. The edible part of the plant is a cluster of flower buds. In addition to head broccoli, there is also sprouting broccoli, which takes less time to grow. It develops numerous side shoots with smaller buds, Sprouting broccoli takes less time to reach the harvest stage, and both the stems and the buds are eaten.
There are many different broccoli varieties and to successfully grow it in your garden, it is key that you select a variety that is suitable for your climate and the time you are planting it (spring or summer).
Broccoli Overview
Where to Plant Broccoli
Choose a planting site (garden, raised bed, or large container) in full sun with fertile, well-drained, and slightly acidic to neutral soil.
Do not plant broccoli in the same spot where you have grown other cruciferous vegetables (Brussels sprouts, cabbage, cauliflower, kale, kohlrabi) in the past two years, preferably longer. Following crop rotation is crucial for members of the brassica family such as broccoli because they are especially prone to diseases, including soil-borne pathogens.
How and When to Plant Broccoli
Broccoli needs a fairly large time window of cool weather to grow. Varieties with a short growth cycle (50-60 days to maturity) are planted two weeks before the last average frost date. They will produce heads and be ready to harvest before the hot summer weather starts. Varieties with a longer growth cycle (60 to 85 days to maturity) are planted in mid- to late summer, about eight weeks before the first expected frost date. They will form heads after the summer heat subsides and will be ready to harvest in the fall.
Many nurseries and garden centers sell broccoli seedlings in the spring, but you can also start your own from seeds indoors 6 to 8 weeks before the last expected spring frost. Sow seeds 1 inch apart and ½ inch deep in small pots filled with seed-starting mix. Keep the seedbed evenly moist and provide a bright light source. When seedlings are 3 to 4 inches tall, transplant them outdoors after gradually exposing them to sun and wind over a few days.
To plant nursery-grown or your own seedlings, loosen the top 5 inches of soil. Dig small holes for each plant or a trench and plant the seedlings at the same level as they were in the pot. Space plants 18 inches apart in rows 24 inches apart. Water seedlings well after planting.
Broccoli Care Tips
Because broccoli needs specific conditions and it is prone to various pests, which require protective measures, it is one of the more demanding vegetables to grow.
Light
The planting location should receive at least 8 hours of full sun per day.
Soil and Water
Broccoli needs rich soil with a pH between 6.0 and 7.0. If the soil is poor in nutrients, incorporate well-decomposed compost before planting.
Consistent moisture is crucial—broccoli that is heat-stressed forms small heads with an off-flavor. Check the soil moisture regularly and water slowly and deeply whenever the soil about 2 inches below the surface is dry.
Temperature and Humidity
Broccoli needs a certain time at or below 50 degrees F to develop its edible flower heads (crown). The number of days or weeks depends on the variety. When daytime temperatures exceed 86 degrees F and nighttime temperatures are above 77 degrees F, the plant usually fails to grow a crown.
Fertilizer
Broccoli is a heaver feeder that requires several fertilizer applications. When transplanting seedlings to the garden, use a starter fertilizer, such as 2-4-2 (twice as much phosphorus as nitrogen and potassium). Three weeks later and again when a central head has started to form, apply a high-nitrogen fertilizer such as 21-0-0. For amounts, follow the label instructions.
Pruning
Standard broccoli does not require pruning. Some varieties of sprouting broccoli, on the other hand, benefit from pinching the central head as soon as it forms to encourage the growth of side shoots. Check if pinching is recommended for the variety you are growing.
Pollination
Because broccoli is harvested before the flower buds open, no pollination is required when growing it in a home garden.
Potting and Repotting Broccoli
Use a container at least 12 to 18 inches wide and deep and with large drainage holes. Fill it with rich, well-draining potting soil. Keep in mind that potted plants need more frequent watering than plants in garden soil.
Repotting won't be necessary, as the plant concludes its lifecycle within one growing season.
Pests and Problems
Two common pests of broccoli are flea beetles and cabbage worms. Use a biological pesticide such as non-toxic Bacillus thuringiensis (BT) or hand-pick the caterpillars and drop them in a bucket of soapy water. To prevent flea beetle damage, protect the young plants with a floating row cover at planting time.
How to Propagate Broccoli
Broccoli is propagated from seed. Note that the plants won't flower until their second year and letting them flower in order to collect seeds will be disappointing because most broccoli varieties are hybrids and their seeds don't produce plants that are true to the parent.
Harvesting
Standard broccoli is ready for harvest when the head is tight and firm. Harvest before any buds open to reveal yellow flowers, which indicate the broccoli is past its peak (although still edible). Cut the stems at an angle to reduce the chance of rotting. Continue harvesting smaller side shoots as they develop.
Sprouting broccoli is harvested repeatedly. Cut the central stem and the side shoots of sprouting broccoli when the stems are 4 to 8 inches long. Continue harvesting the side shoots every couple of days in warm weather and about once a week in cool weather to encourage the development of more stems.
Types of Broccoli
'Green Magic'
This variety for summer harvest is valued for its heat tolerance. The heads are smooth, well-domed, and uniform. 57 days to maturity
'Imperial'
While other broccoli varieties will only form dense heads in cool temperatures, this variety forms its small, dark green heads in warm weather. It is suitable for summer and early fall crops as well as winter harvest in the South although is does better with long days. 71 days to maturity
'Packman'
Consider Packman for an early-maturing broccoli that is adapted to different climates and soils and can be grown all season. The large heads up to 8 inches in diameter have a mild flavor. 50 days to maturity
'Burgundy'
This sprouting broccoli has sweet and tender purple buds and purple-green stems. It produces numerous side shoots for a continuous harvest. 37 days to maturity
'Apollo'
For a novelty broccoli that matures very fast, try this cross between broccoli and gailon or Chinese broccoli (Broccoli x Gailon). It does not form traditional heads, it is smaller and darker than broccoli with a stronger flavor and the whole plant is eaten like greens. 30 days to maturity
Garden Plans for Broccoli
Easy Children's Vegetable Garden Plan
This easy children's vegetable garden plan will please gardeners of all ages with unusual and fun-looking vegetables such as kohlrabi, 'Scallop' summer squash, and 'Kaleidoscope' carrots A few 'Pacman' broccoli plants add to the mix of textures and flavors. There's even a shade-providing playhouse made out of bean vines.
Spring Vegetable Garden Plan
Enjoy the freshest flavors of the season with this simple spring vegetable garden plan. Designed for a four-foot-square raised bed, it nestles in 10 different cool-season crops that do their best growing in lower temperatures and even tolerates a light frost. Just make sure to situate this garden in full sun.
Fall Vegetable Garden Plan
Broccoli and other cool-season crops are part of this fall garden plan for a four-foot-square raised bed. Note that this plan is designed to follow the summer vegetable garden plan, so it includes previously planted tomatoes, peppers, and green beans that will be reaching maturity as your fall-planted crops start growing. If you want to just start with this plan, fill the summer vegetable spaces with more lettuce and spinach.
Frequently Asked Questions
- How long does it take to grow broccoli?The time it take to grow broccoli varies. Spring-planted varieties take about two months while summer-planted varieties take up to three months until harvest. Sprouting broccoli takes the least amount of time; you can start harvesting it in as little as 5 to 6 weeks.
The time it take to grow broccoli varies. Spring-planted varieties take about two months while summer-planted varieties take up to three months until harvest. Sprouting broccoli takes the least amount of time; you can start harvesting it in as little as 5 to 6 weeks.
- Does a broccoli plant keep producing?Standard broccoli produces one large head but if the plant is healthy and vigorous, it might develop smaller side shoots after you have harvested the central head.
Standard broccoli produces one large head but if the plant is healthy and vigorous, it might develop smaller side shoots after you have harvested the central head.
- What are good companion plants for broccoli?Members of the Allium family (garlic, onions), beets, celery, lettuce, spinach, and potatoes as well as rosemary and dill are all good companion plants for broccoli.
Members of the Allium family (garlic, onions), beets, celery, lettuce, spinach, and potatoes as well as rosemary and dill are all good companion plants for broccoli.