How to Plant and Grow Broccoli
Skip the grocery store produce section. Learn how easy it is to plant and grow tender, sweet broccoli in your own garden this season.
Garden-grown broccoli florets are tender and sweet, with a flavor that store-bought broccoli just doesn't compare to. With some good timing and a little bit of preparation, broccoli is easy to grow from seed or seedlings from a local plant nursery.
Choosing Which Broccoli Plants to Grow
Shopping for seeds and seedlings is part of the fun of growing broccoli. Some varieties have been bred to produce a large, central head, while others may form many smaller florets or spears (in the case of broccoli raab). Broccoli heads can be purple, yellow or green. In addition to varieties bred for appearance, there are also selections available with increased heat resistance that are slow to bolt (or flower) as well as disease-resistant varieties.
Getting the Site Ready
Broccoli will grow its best in a spot with at least six hours of direct sunlight per day, rich soil and consistent moisture. Broccoli plants are heavy feeders and need fertile soils to thrive. Mix a healthy amount of manure, compost or cover crops into the garden bed to add nutritious organic matter to the soil. Cover crop residue will need a few weeks to break down before planting broccoli.
It's always a good idea to perform a soil test at the beginning of the season to learn the pH level (level of acidity), nutrient availability and the amount of organic matter in your vegetable garden's soil. Many soil testing services include instructions to improve your soil quality for specific crops along with detailed information about the type of fertilizer to apply.
If you're growing broccoli in an established garden, avoid planting where broccoli or its cole crop relatives (including cabbage, kale, turnips, Brussels sprouts and kohlrabi) have grown in the last three years. Why? These plants are susceptible to many of the same pests and diseases, which can build up in the soil over time. Try grouping related crops together during the season and growing them in a different spot each year.
How to Plant Broccoli
When Does Broccoli Grow Best?
Broccoli grows its best at temperatures between 60 and 75 degrees, but it can withstand much colder temperatures, making broccoli the perfect candidate for spring and fall vegetable gardening in most areas of the country. In northern climates, broccoli can be grown as a summer crop, and in the Deep South it grows through the winter. Check with your state or county extension service to learn the optimal season to start growing.
Start Indoors for Spring
Broccoli plants are easy to grow from seed, although you may need to start plants inside for a spring crop to protect them from frigid temperatures. Sow your seeds indoors four to six weeks before the average last frost in your area. Seeds should begin sprouting after about a week. Give your broccoli seedlings plenty of sunshine by placing plants by a sunny window or under a bright light.
"Harden off" or acclimate your seedlings to outdoor temperatures by gradually increasing the amount of time they spend outdoors. A week or two before you plan to plant your broccoli out in the garden, place young broccoli plants in a protected spot outside during the day, and bring plants back inside overnight. If temperatures are expected to dip below 45 degrees, keep plants inside for the day.
Sow Outdoors for Fall
Broccoli seeds can be planted directly into the garden for a fall crop in many parts of the country. Start your fall succession of broccoli by planting seeds between your summer veggies. The established summer crops will shade and protect broccoli seedlings from heat. Broccoli plants will take center stage as warm season veggies decline in cooler weather. Check with your local extension service to learn when the best time to start fall-sown broccoli is in your area.
Planting Broccoli in the Garden
You can also buy broccoli seedlings from your local garden center rather than growing plants from seed. When it's time to plant your broccoli in the garden, check the plant label or seed packet for spacing instructions. A good rule of thumb is to allow about 2 feet of space between plants.
Growing and Caring for Broccoli Plants
Give broccoli between 1 and 2 inches of water a week throughout the growing season to develop firm and sweet-tasting heads. Water deeply to train roots to grow further down into the soil; quickly sprinkling the soil encourages surface roots that are more susceptible to drought stress.
Use a watering wand or watering can to water the soil well. When water begins to run off from below the plants, pause to allow the water to percolate into the soil, then water again. You can also use a soaker hose or a drip line to slowly deliver water to the soil below the plant.
Fertilize as Needed
If your soil test report noted any nutrient deficiencies, you can improve your broccoli's development by adding a fertilizer at the beginning of the season and again by side-dressing when plants are about 4 inches tall. Over-fertilizing can cause problems including hollow stems or plants favoring leaf growth over head development.
Weeds compete with broccoli plants for sunlight, water and nutrients. Remove weeds while they're small to eliminate competition early and to avoid disturbing your broccoli plant's roots. Use a healthy layer of compost or straw mulch around plants to discourage weeds, conserve water and add organic matter to the garden.
Scout for Health Issues
Keep an eye out for potential health problems, including pests like flea beetles, cabbage worms and loopers, and aphids, and diseases such as club root and hollow stem. Experiment with companion planting to deter pests, attract predators and improve soil quality.
If you've struggled with pest pressures in the past, protect your broccoli plants with a floating row cover. Combat disease by choosing resistant varieties and rotating the location where you grow broccoli and its cole crop relatives each season.
How to Harvest Broccoli
Depending on the variety and environmental conditions, your broccoli plants may be ready to harvest about 12 weeks after planting. Cut broccoli heads before yellow flowers begin to open from the buds. Use a sharp knife to cut the stem about 6 inches below the head. Once the large, central head is removed, smaller heads will usually develop from the side shoots. Keep picking these smaller florets to encourage continued production. Florets are delicious fresh from the garden, or you can freeze your broccoli to use later.
When broccoli florets are ready for picking, don't delay. Just a day or two can make all the difference, with the tight cluster of buds quickly opening to yellow blooms. "Bolting" (or flowering before florets can be harvested) is a common problem with broccoli. If your broccoli begins to bolt, go ahead and remove the flowering shoot and keep an eye on new florets budding up from the side shoots so that you can harvest them quickly before they begin to flower. If bolting is an ongoing issue in your garden, look for heat-tolerant varieties that are slow to bolt.