Learn how to grow cauliflower from seed to harvest! This cool-season crop thrives in spring and fall. Discover expert tips to grow big, beautiful heads of cauliflower. HarvestingCauliflowerSeeds. To harvest the seeds, gather the seed stalks when the seed pods are fully mature and dry on the plant. Use a screen to winnow the chaff from the seed. Garden zones 3-7: Sow seeds indoors for cauliflower 10-12 weeks before your last spring frost date Garden zones 8-11: Transplant cauliflower in fall. CauliflowerSeeds.png. Plant these in the spring. Takes 12 days to produce a large cauliflower. Information. Crop: Cauliflower.png Cauliflower. Growth Time The Cauliflowerseed is a gradient between white and green. The Cauliflower crop has a randomized number (usually three to four) green leaves titled upwards and away from each other. Keep reading to discover how to plant cauliflower from seed. By following these simple tips and tricks, you’ll enjoy a bountiful harvest that will leave you feeling like a true cauliflower... Expert advice from Eden Brothers on planting cauliflower, including the best time to plant, garden location, and harvesting tips. If you planted the cauliflower for a fall harvest, be sure to pick it before it bolts (when it starts to flower and set seeds) or before a hard frost hits. Raise cauliflower from seed to harvest with our growing guide.How to Grow Cauliflower Plants. Plant cauliflowerseeds indoors when there's cool weather in the spring or in the fall. For the best harvest, you will need to grow cauliflower when temperatures are between 55º and 80ºF. Cauliflowerseeds can be sown outdoors or started indoors.