Broccoli prefers soil with a pH between 6.0 and 7.0. To increase the fertility of your soil, mix up to four inches of mature compost into your soil. If your soil is in particularly poor condition, also add a high-nitrogen organic fertilizer to enrich the soil. Organic fertilizers like alfalfa, cottonseed meal, and manure are good choices for planting broccoli.
While broccoli prefers full sun, it will tolerate some shade.
Broccoli does best when started inside and transplanted at about 4” high. This usually takes about 4-6 weeks. For a summer harvest, sow seeds 6-8 weeks before the last spring frost, planning on transplanting your seedlings into your garden beds about 3 weeks before the last spring frost. For a fall harvest, determine your first fall frost date and count backward 85 to 100 days (depending on variety) to figure out when you need to start your seeds. Floating row covers can extend your season by several weeks.
Depending on variety, space your plants 12-24” apart in rows 36” apart.
Apply an organic mulch made of mature compost, leaves, or bark to keep weeds in check and soil temperature regulated.
Allow your plants between one and one and a half inches of water per week. Broccoli likes moist (but well-drained) soil. Make sure not to get the budding broccoli crowns wet when watering. Doing so causes them to mold. In particularly hot or dry conditions, increase the amount of water you feed your plants.
Fertilize your plants about three weeks after planting. Use an organic, nitrogen-rich fertilizer when your broccoli plants begin to form new leaves. Fish emulsion works well for fertilizing broccoli plants. You can continue to fertilize the plants about once a week until they are ready for harvest.
Broccoli plants have very shallow roots. If you disturb the soil you may accidentally break roots and damage your broccoli plants. If weeds develop around the plants, suffocate them with mulch instead of plucking them from the ground to avoid disturbing the roots.
You want to harvest your broccoli crowns when the buds are tightly closed and dark green. Avoid waiting until the buds begin to flower into light green or yellow flowers. Cut the crown where it meets the stem using garden shears. Avoid breaking the crown off. A clean cut will better encourage new growth. With a healthy cut, the broccoli plant should grow small shoots from the side of the stem. You can continue to harvest the small shoots, and the plant should produce more.
Read More: https://sowtrueseed.com/blogs/gardening/how-to-grow-broccoli