How to Grow Broccoli

Broccoli is a perennial garden favorite, and no wonder: it’s fairly easy for the home gardener to grow, can be planted in either the spring or fall, has multiple harvesting times, a healthy dose of vitamin A and D, and is a versatile food for the home cook. With just a few tips on how to grow broccoli, you can be enjoying your own this spring.

Broccoli growing requirements

Broccoli is a part of the cabbage family and is a cool season crop that prefers temperatures in the 60’s for optimal growth and production. Due to the cool weather requirements they should be planted in either spring or fall when the temperatures and soil are cooler. Broccoli is a heavy feeder and performs best in fertile, well-drained, moist soil. Adding organic matter can help improve the quality of the soil, as can nitrogen. Apply fertilizer when transplanting and again two weeks later. The soil should be consistently moist, but not wet.

Applying a top layer of mulch will help keep the ground moist and cooler. Like most vegetables, broccoli requires at least 6 hours of sun a day to produce the best crop. For those who want to harvest broccoli all summer long, there are new heat-tolerant varieties of broccoli that perform much better in the summer heat than the traditional varieties. Two heat-tolerant varieties to try are Green Goliath and Green Comet.

When to Plant Broccoli

Broccoli is most successful if planted in the garden as a seedling transplant instead of by direct seed. Broccoli is very hardy and can be planted in the garden earlier than many other vegetables, sometimes up to 4-6 weeks before the last frost date. To find state-by-state last frost dates go to: http://usagardener.com/breaking_ground/frost_dates_usa.php.

If you decide to start your own seedlings indoors you should begin about 6-8 weeks before you expect to plant them in your garden. Make sure the transplants are sturdy before planting them in the garden. When you put them in, place them slightly deeper than they were grown for better support. You will also want to be sure to acclimate them first to prevent transplant shock. Take your seedlings outside for a couple of hours the first day and gradually increase the length of time. After a few days you can plant them in your garden.

If you directly sow seeds, plant them about ¼ to ½ inches deep. As your plants grow you should thin the seedlings to keep them about 18-24 inches apart from each other. Be sure to leave enough room between rows so that you can properly water, weed, fertilize and harvest your crop; 36 inches is usually sufficient.

Problem pests and insects for broccoli

Broccoli can be very susceptible to certain pests. Two of the most common pests are cabbage loopers and aphids.

Cabbage loopers can cause extensive damage to broccoli plants. Cabbage looper moths overwinter in cocoons and typically begin to lay eggs on plants in May. These eggs hatch in 3-4 days as caterpillar larva and begin feeding on plants like broccoli for 2-3 weeks. The caterpillars damage plants by chewing large holes in their leaves. Large numbers of caterpillars can ruin entire plants. After feeding on plants, the caterpillars pupate in a cocoon on the under- leaves of plants for 2 weeks. This can begin a whole new cycle of cabbage loopers.

The least costly and easiest way to get rid of cabbage loopers is to physically pick them off the plants. Once you identify the Cabbage looper caterpillar they are easy to spot and can be physically removed from the plant. Plants can also be covered with thin netting to keep caterpillars at bay. As a last resort, commercial insecticides can be used.

Aphids are small, soft-bodied insects with long, slender mouth parts that they use to pierce stems, leaves, and other tender plant parts and suck out plant fluids. There are literally hundreds of aphid species. They often hang out on the underside of plant leaves. Damage cause by aphids appears as curled, misshapen or yellow leaves. If you only have a few cabbage leaves that are infected with aphids, you can simply pick those leaves off and dispose of them.

Another popular, natural method of removing Aphids is with a strong spray of water that literally knocks them off the plant. If you find these methods unsuccessful you can try an insecticidal soap. This soap must be thoroughly applied to all areas of the plant. You will probably need to use multiple applications of this as it only kills the aphids that are present and active on the day it is used.

Maturity, harvesting and storage of broccoli

It takes broccoli about 85-90 days to form its first head. You can harvest your broccoli when the center head is fully developed, but before it begins to separate and flower. If the broccoli has already begun to open and flower (the flowers are bright yellow) it is past maturity. Cut the large center head along with about 5-6 inches of stem. After you harvest the first head, many varieties will produce secondary shoots with smaller heads for many weeks.

Broccoli should be kept in your refrigerator in a plastic bag that has adequate air circulation. You should consume the broccoli within about 3-4 days. Do not store broccoli at room temperature because it takes on an undesirable woody texture. You should not wash your broccoli before storing it in the refrigerator; it will quickly become moldy. You can wash it just prior to eating it.

Broccoli is a very versatile vegetable and can be enjoyed in salads and with dips, cooked or steamed in water, added to stir-fry, casseroles and soups (think Broccoli and cheese!), or simply raw as a healthy snack.

Common Questions and Answers About How to Grow Broccoli

Are broccoli leaves edible raw?

Broccoli leaves may appear a bit odd-looking but they are edible both raw and cooked. The younger leaves, also known as auxiliary florets, are tender enough to pick right off the plant, rinse, and toss directly into a salad, but the younger side leaves aren’t the only leaves you can snack on. The giant leaves that surround the crown are edible too, as long as you remove the midriff, which is a bit too chewy and stringy for most palates. Broccoli leaves are not just for consuming raw in salads, you can also cook them in several different ways, and heat makes them even sweeter.

Are broccoli leaves toxic?

Broccoli leaves are one of several completely edible parts of the broccoli plant. In fact, most parts of the broccoli plant can be eaten, including the flowers, stalks, stem, and crown. The only toxic, or poisonous parts of the broccoli plant are the roots and the seeds.

Can I eat broccoli leaves?

Broccoli leaves are completely edible both in raw form and cooked. This is true for both the younger leaves on the side of the plant known as auxiliary florets which are often consumed raw due to their tender texture, and the larger, more mature leaves that surround the crown, which are often cooked in different ways. Adding heat to the leaves makes them sweeter.  When eating the larger leaves, be sure to remove the midriff, however. It’s not toxic, just stringy and hard to chew and swallow.

Can I freeze broccoli leaves?

The leaves and stems of the broccoli plant must be blanched before freezing or you will wind up with a science project in your freezer. Freezing broccoli leaves and stems raw without blanching them first results in a nastily bitter, icky drab green, shriveled up mess. Blanching leaves and stems will make freezing a non-issue, as the process will preserve the bright green color and the delectable flavor. Blanch your broccoli florets and stems by steaming for five minutes or boiling for three minutes. Allow them to cool before transferring them to the freezer in a freezer bag or airtight container.

Can you grow broccoli in a five-gallon bucket?

A five gallon bucket is an ideal size container to grow an individual broccoli plant in. Just don’t try to plant more than one broccoli plant in a five-gallon bucket, or you will end up with two mini broccoli plants instead of one big one.

Can you grow broccoli in the summer?

Broccoli is a cool season crop, so you won’t get much good growth during the hottest parts of the summer. But, in cool climate areas some spring broccoli varieties can continue being grown and harvested into the early months of the summer. Also, fall and winter broccoli crops are planted in mid to late summer until early fall.

Can you regrow broccoli from the stalk?

Unfortunately, broccoli cannot be harvested for months on end like many other garden vegetables. However, broccoli can be harvested several times throughout the growing season, depending on the climate in your region. Young shoots are tender and sweet, so don’t wait until the heads become too large to start diving in. As a general rule, broccoli can be harvested two or three times for a period of up to three months.

The first harvest will take the large center head. Once cut, the plant will continue making smaller side heads for several weeks. Harvest each of these side heads when they are still small, tight, and firm. If you see yellow flower buds begin to appear, it should be cut immediately. As for how long you might be able to harvest your broccoli plants, that is up to the elements. During cool weather, broccoli can be harvested repeatedly. When the weather turns hot, your broccoli plants stop producing.

Do I need to cover my broccoli plants?

Broccoli plants do pretty well without a lot of protection in most cases. However, there are situations in which broccoli needs a cover to protect them from the elements, or from pest infestations. Broccoli is a cool climate vegetable. It does best growing in temperatures between 60 and 70 degrees F. But it can easily be damaged by an unexpected heat wave or freeze.

Heat waves can cause broccoli plants to bolt early and frost damage causes broccoli florets to get a mushy texture. If the temperatures are about to get cold for an extended period, protect your broccoli crops with row covers, plastic gallon jugs with the bottoms cut out, newspapers, or hotcaps. If a brief cold front is coming one evening, cover your broccoli crops overnight with an old blanket or a floating row cover.

Does broccoli come back every year?

Broccoli is a biennial, meaning it grows in the first year and flowers in the second year, however, broccoli plants can go to seed in the first year if they are planted in the spring. There are no varieties of broccoli that come back year after year. Broccoli is not a perennial plant, it has no USDA hardiness zones, and it needs to be reintroduced into the garden every year in order to continue cultivation.

Does broccoli have deep roots?

Broccoli is considered a shallow-rooted vegetable. However, even shallow-rooted vegetables have some pretty long roots, extending between 12 and 18 inches into the soil.

How deep are broccoli roots?

Broccoli is considered a shallow-rooted vegetable, and it is categorized with other plants that have roots which extend 12 to 36 inches into the soil. Broccoli roots specifically, typically extend only 12 to 18 inches deep.

How do I know when my broccoli is ready to harvest?

Broccoli heads are ready to harvest when the size of the heads stop growing and turn a deep shade of green, with small, tightly compacted buds. Harvest heads immediately if you see any signs of flowering. Florets and side shoots will continue growing after the main head has been harvested. Harvest the side shoots when they turn deep green and become firm to the touch.

How do you know when broccoli is ready to harvest?

You will know when your broccoli plant is ready to harvest when you notice that it has stopped growing. The best time to harvest your broccoli heads is early in the morning when the buds are firm and tight, just before the head starts to flower. If you see yellow petals beginning to emerge from the heads, harvest immediately as the quality of the fruit will decrease rapidly after the plant bolts.

How do you pick broccoli from the garden?

Early in the morning, when your broccoli heads have stopped growing and the buds are firm and tight, just before the heads begin to flower, it is time to harvest your broccoli heads. Cut the heads away from the plant, removing at least six inches of stem. Make a slanted cut on the stalk to allow the water to slide away easily. If you notice yellow petals beginning to emerge from the heads, harvest immediately as the quality of the fruit will decrease quickly after bolting.

How do you store fresh broccoli?

Fresh broccoli should be eaten as soon as possible, as even using a perfect storing technique, fresh broccoli will not keep for very long. To store for brief periods, mist the unwashed heads, wrap loosely in moist paper towels, and refrigerate. Do not store broccoli in a sealed container or a plastic bag. Even with this method, you will want to consume all of your fresh stored broccoli within two to three days.

How far apart do I plant broccoli?

Each broccoli plant should be spaced 18 inches apart in rows 24 inches apart so that you can walk between them. You can plant two or three plants abreast within a single row, however, to minimize aisle space.

How long do broccoli sprouts take to grow?

Three or four days after the broccoli seeds start to sprout, the seedlings will begin to develop dark green leaves. Once the seedlings have several dark green leaves each, it is time to harvest your sprouts. This process should take no more than a week from the time you planted your seeds.

How long does a broccoli plant live?

Broccoli plants that are grown from seed become ready for harvest between 100 and 150 days. Broccoli grown from transplants matures and is ready to harvest in 55 to 80 days after transplanting. After the heads are harvested, the plant will live and continue to produce side shoots for several weeks, or until temperatures get too high or low.

How many broccoli seeds are in a hole?

When planting broccoli, seeds should be planted in a ¾ inch hole with three broccoli seeds per hole. Each hole should be spaced at least 12 inches apart for calabrese and at least 24 inches apart for sprouting broccoli cultivars.

How many heads of broccoli do you get from one plant?

Broccoli plants can be harvested two to three times for a period of up to three months. The plant first produces a large head in the center of the plant. Once this main head has been harvested, it will grow several smaller side heads for the next several weeks. Heads can be harvested when they are small, tight, and firm to the touch.

How many times can you pick broccoli?

Broccoli plants can be harvested two to three times for a period of up to three months. The plant first produces a large head in the center of the plant. Once this main head has been harvested, it will grow several smaller side heads for the next several weeks. Heads can be harvested several times after the main head is harvested. The best time to harvest side heads are when they are small, tight, and firm.

How often should broccoli be watered?

Broccoli plants require a steady supply of moisture in order to thrive so water regularly, giving your plants one to one and a half an inch of water per week if the rain does not provide sufficient irrigation. Keep the soil moist to the touch but never soggy for best results.

How tall do broccoli plants get?

Broccoli plants grow vertically, rather than horizontally. At maturity, broccoli plants can grow up to 2 and ½ feet tall, or 18 to 36 inches high.

Should broccoli be refrigerated?

If you are storing fresh broccoli for a short period of time, refrigeration is recommended. Mist the unwashed heads with water and wrap them loosely in a damp paper towel, then place them in the refrigerator. Try to consume all of your fresh broccoli within just two to three days as fresh broccoli goes bad rather quickly, even when refrigerated.

What causes broccoli to bolt?

Broccoli is a cool weather plant, so when temperatures get too warm for its liking, it is quick to bolt, or start producing flowers. Bolting practically ruins your broccoli crop so do your best to harvest all of your broccoli heads before bolting occurs, when heads are still composed of small, tightly wound, firm green buds.

What do you feed broccoli plants?

For feeding broccoli plants, use a high-quality, all-purpose 20-20-20 fertilizer when transplanting your young broccoli plants into their final location, follow package directions for application instructions. Liquid fertilizers are easier to apply but granular products are also relatively easy and usually cheaper than liquid fertilizers. Be sure to water your broccoli right after fertilizing to allow the nutrients to soak down into the root zone.

Ammonium sulfate should be added at a rate of one half cup for 10 feet of row as plants begin to produce fruit. Add another feeding of ammonium sulfate should be given at heading time. You may also consider using a micronutrient fertilizer to help ensure that the soil you are using has all the essential nutrients that your plants might need to produce the best possible fruit.

If you are growing broccoli in containers, choose a timed release 10-10-10 or 14-14-14 fertilizer formula at planting time, mixing it thoroughly with a standard potting mix. About midway through the growing season, feed plants again with a water soluble fertilizer, following the directions on the fertilizer label.

What does broccoli look like when it grows?

Broccoli is an interesting looking plant to be sure. When it first sprouts, baby seedlings have only two leaves which resemble two fat hearts on either side of the stem. As the plant develops, the crown, or head begins to emerge from the center of the main stalk. Around the head, large, broad, thick leaves spread out in each direction. The head of the plant resembles a compact, bushy tree, that is composed of tiny blue-green flower buds.

What is broccoli bolting?

Broccoli is a cool weather crop, so when it gets too hot, broccoli plants start to flower, or bolt, which practically ruins your harvest. Though broccoli that has flowered is still perfectly edible, it’s not quite as tasty and it loses most of its nutritional value once it has bolted.

What is eating the leaves of my broccoli?

There are quite a few insects that enjoy eating broccoli just as much as humans do. Some of these, such as aphids, can be contained by blasting them off the plants with water from your garden hose. Some pests require floating row covers to keep them away. You can also treat your broccoli plants with biological pesticides, such as Spinosad, or organic insecticides, such as BT.

What is the best way to grow broccoli?

Broccoli grows best in a location where it will receive at least six hours of direct sunlight per day. Broccoli performs best in a well-draining, compost-rich soil with a pH between 6.0 and 6.8. Broccoli is a cool season crop which grows best in air temperatures between 45 and 75 degrees F.

What kind of soil does broccoli like?

Broccoli thrives in a compost-rich, fertile, well-drained soil with a pH preferably between 6.0 and 6.8.

What month do you harvest broccoli?

The specific time of harvest for broccoli depends on the variety planted and the region you are growing in. Most varieties have side shoots that will continue to develop long after the main heads have been harvested. You can continue to harvest from one plant for several weeks, in some instances, from spring to fall, off of the same broccoli plants. As a general rule, broccoli plants grown from seed are ready for harvest between 100 and 150 days after planting, and broccoli plants that are grown from transplant are ready 55 to 80 days after the transplant occurs.

When should broccoli be pruned?

If you have decided to prune your broccoli’s side and lateral shoots so that it focuses on growing a larger head, you can prune your broccoli plant early and often, anytime lateral or side shoots begin to develop. If you are pruning the main head to promote multiple large side heads, you should harvest the main head about one month after transplanting into your garden bed.

Where does broccoli grow naturally?

Native to the eastern Mediterranean and Asia Minor, sprouting broccoli has been cultivated in Italy since ancient times in the Roman empire. It was introduced to England and America in the 1700’s.

Where does broccoli grow on the plant?

The head of the broccoli plant, which is the part of the plant that is commonly cultivated and eaten, grows from the top of the central stalk of the broccoli plant. It is surrounded by broad thick leaves that surround the head on all sides.

Where is the best place to store broccoli?

The best place to store fresh broccoli is in the fridge. Mist the unwashed heads with cool water and wrap in a damp paper towel and place in the fridge. Consume within two to three days. The best place to store broccoli for extended periods is in the freezer after chopping the heads into small pieces and blanching them to help them retain freshness after being thawed.

Why did my broccoli turn into flowers?

Broccoli is a cool weather crop, so when it gets too hot, broccoli plants start to flower, or bolt, which drastically reduces the nutrient levels of your broccoli. Though bolted broccoli is still perfectly edible, it’s not quite as tasty and does not have the same texture as traditional broccoli.

Why is broccoli so smelly?

Fresh broccoli doesn’t have a bad odor, but as soon as broccoli starts to take a turn for the worst, it begins to emit a sulphurous odor. Cruciferous vegetables like broccoli, cauliflower and cabbage contain high levels of sulphur than most vegetables. When decay starts to set in, the hydrogen ions in the water react with the sulphur compounds to form low levels of hydrogen sulphide gas, which gives off a characteristic rotten egg odor.

Broccoli Growing Reference Chart

Life cycle	Technically a biennial, completing its lifecycle in two growing seasons. Most gardeners grow it as an annual to harvest before flowering to seed.
Plant type	Annual or biennial
Native To	Mediterranean region
Scientific Name	Brassica oleracea var. italica.
USDA Hardiness zone	2-11
Days to Maturity	50-100 days
Sun Requirements	Full sun
Planting requirements	Well-drained soil, pH between 6.0 and 7.0, consistent moisture
Spacing	18-24 inches apart
Planting Depth	1/4-1/2 inch deep
Plant Height	18-36 inches tall
Plant Spread	18-24 inches wide
Water Requirements	Consistent moisture
Common Pests	Aphids, Cabbage Loopers, Cabbage Worms, Cutworms, Flea Beetles, Harlequin Bugs, Cabbageworms, Slugs, Snails
Common Diseases	Clubroot, Downy Mildew, Fusarium wilt, Powdery Mildew
Soil Requirements	Well-drained, pH between 6.0 and 7.0
Soil PH	Between 6.0 and 7.0
Companion Plants	Beets, Celery, Chamomile, Dill, Lettuce, Marigold, Mint, Nasturtiums, Onions, Rosemary, Sage, Spinach, Swiss Chard,Thyme
Popular Varieties	Calabrese Green Sprouting (Heirloom), De Cicco (Heirloom), Waltham 29 (Heirloom), Arcadia (Hybrid), Belstar (Hybrid), Gypsy (Hybrid), Marathon (Hybrid), Packman (Hybrid)
Attracts Pollinators	Honey bees
Time to Harvest	50-100 days after planting
Planting calendar	Spring or fall depending on your location and climate
Cool Season or Warm Season Crop	Cool season

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Want to learn more about Broccoli?

Visit these sites:
The University of Illinois Extension has a vegetable garden guide to growing broccoli.

Learn more about growing broccoli from the Ohio State University Extension fact sheet on growing broccoli and cauliflower in the home garden.