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.
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.