Sowing Dates for Broccoli

Spring Planting

• Sow broccoli seeds directly outdoors in the early spring. The best time to plant the seeds is two or three weeks before the last frost date in the area. When you plant the seeds, you should be able to work the soil. Ideal soil temperatures are between 45 degrees and 85 degrees Fahrenheit. The seeds can germinate in soil that is as cool as 40 degrees. When sowing directly, plant seeds 1 inch deep and 3 inches apart.

Fall Planting

• The type of winter you usually experience determines when you can plant broccoli for a fall crop. If you experience a freezing winter, it's best to sow the seeds directly outdoors in July or August, or from 85 to 100 days before the first frost for your region. If you live in a slightly warmer climate, above the United States Department of Agriculture's hardiness zone 7, you can sow the seeds later in the fall, then harvest the broccoli first thing in the spring.

Indoor Sowing

• Start broccoli seeds indoors for the most control over soil temperatures and other conditions. If you sow the seeds indoors, plant them six to nine weeks before the last frost in your region. The ideal soil temperature for starting the seeds is 75 degrees Fahrenheit. The seeds should germinate within a week. Once the seedlings have emerged, keep them at a consistent temperature between 60 and 65 degrees, in full sunlight. Move the plants outside when they are about 6 inches tall, have no more than four sets of true leaves, and are between 4 and 6 weeks old.

Location and Care

• Broccoli needs full sun to thrive. The plants can live with partial shade, but will take longer to grow and mature. Protect the plant from extreme temperature shifts by covering young seedlings with floating row covers on nights when the temperature dips below 40 degrees. When things start to heat up, you can protect the plants from the heat with a few inches of mulch. Give the plants at least an inch of water weekly.