Cauliflower grows best in cool weather and has tasty white heads that are full of nutrients. But for a good harvest, you need to know the right way to plant, especially when it comes to planting the seeds. Many gardeners want to know how many cauliflower seeds to plant in each hole. In this full guide, we’ll tell you everything you need to know about planting the right number of seeds for strong cauliflower growth.
When to Plant Cauliflower Seeds
Cauliflower grows best in cool weather; it needs temperatures to stay between 60°F and 70°F while it’s growing. Depending on the variety, it takes about 2 to 4 months from seed to harvest. Here are some tips on when to plant cauliflower seeds.
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For spring harvest, directly sow seeds in late winter or start indoors 6-8 weeks before the last expected frost date.
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For a fall harvest, directly sow seeds in mid to late summer or start indoors 12-14 weeks before the first fall frost date.
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Pests can’t hurt young seedlings when you start seeds indoors, giving you more control over the growing conditions.
How Many Seeds Per Hole?
When sowing cauliflower seeds either directly or in containers, the recommended number is 2-3 seeds per hole. Here are some key reasons why:
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Planting more than one seed increases the chances that more than one will grow. Cauliflower seeds can have germination rates around 80%.
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The extra seeds allow you to select and retain only the strongest seedling after thinning them.
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Spacing the seeds 2-3 inches apart reduces root disturbance when thinning later.
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After seeds germinate, thin down to just 1 plant per hole, snipping off the others.
Step-By-Step Planting Guide
Follow this complete step-by-step guide to sow cauliflower seeds successfully:
Starting Indoors
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Fill seed starting containers or cells with moist seed starting mix.
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Plant seeds 1⁄4-1⁄2 inch deep, spacing 2-3 seeds per individual cell or compartment.
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Maintain consistent moisture and provide plenty of light as the seeds germinate.
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Once seedlings emerge, thin to just 1 plant per cell, keeping the strongest.
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Harden off plants for 7-10 days before transplanting them outside.
Direct Outdoor Sowing
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Prepare soil well in advance by mixing in 2-3 inches of compost or other organic material. Cauliflower needs nutrient-rich soil.
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Wait until the soil warms up to at least 45°F before sowing seeds directly.
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Sow seeds 1⁄4-1⁄2 inch deep and 12-18 inches apart in rows spaced 30-36 inches apart.
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Place 2-3 seeds per hole and thin later.
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Ensure the soil remains consistently moist for proper germination.
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Gradually thin seedlings, leaving just 1 plant every 12-18 inches.
Proper Spacing & Thinning
Proper spacing and thinning of cauliflower seedlings is crucial:
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After germination, thin to 1 plant every 12-18 inches within rows spaced 30-36 inches apart.
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Avoid overcrowding which causes smaller, underdeveloped heads.
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Thin gradually over 2-3 weeks to reduce transplant shock to remaining seedlings.
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Water seedlings well and provide a nutrient boost after thinning to aid recovery.
Providing Optimal Care
Here are some key tips for taking care of your cauliflower plants:
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Water transplants frequently after first planting out.
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Use mulch to conserve moisture once plants are established.
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Supply 1-2 inches of water per week if rainfall is insufficient.
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Maintain consistent soil moisture throughout growth to avoid loose, “riced” heads.
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Control pests like cabbage worms, aphids, flea beetles which affect cauliflower.
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Rotate planting sites to prevent fungal diseases like clubroot.
Harvesting Perfect Heads
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Monitor heads frequently as they mature and harvest immediately when the curds are tight and firm.
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Cut heads with 4-6 inches of stem still attached.
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Store harvested heads at 32-40°F with high humidity, where they will keep for 2-4 weeks.
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Allow some plants to go to seed for saving seeds for next year’s crop.
By sowing 2-3 cauliflower seeds per hole and following the best planting, growing, and harvesting practices you can enjoy a bountiful harvest. Pay close attention to proper spacing, thinning, moisture, and care for robust plants and beautiful heads.
Problem: Head not developing
If your plant has lots of leaves but still no head, or if the head seems on the small side, there might be several different culprits. Your plant might be low on nutrients or not receiving enough water. This is causing it to feel too stressed out to spend energy developing a large head. The weather could also be too warm.
Support your plants with some fresh compost around the base, and make sure theyre getting consistent water. If its above 85°F during the day, consider using shade cloth to keep your plants nice and cool.
How to Start Cauliflower Plants
Cauliflower needs at least 70 days to grow from seed to harvest, so I suggest starting seeds indoors at least 30 days before moving them outside. Place just one seed per cell and barely cover them with soil.
Cauliflower seeds germinate best in cool soil, so dont use a heat mat under your seed starting trays. Don’t allow the soil to dry out before seeds have germinated, which usually takes about 8 to 10 days. Make sure to harden off your cauliflower seedlings before moving them permanently to the garden space.
If seed starting indoors isnt for you, buy some plant starts from a local nursery or farmers market.
Transplant your cauliflower plants to the garden once the temperature is ideal. Space each plant 2 to 3 feet apart in rows if youre growing in the ground. Cover your plants with a floating row cover or garden mesh just after planting to prevent caterpillars.
Water in plants well and keep the soil consistently moist for the first 2 weeks after planting.
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FAQ
How many seeds do I put in each hole?
Generally, you should plant two to three seeds per hole.
How many cauliflower heads do you get from one plant?
Each cauliflower plant typically produces one head. After the main head is picked, the plant usually doesn’t make any more, but some gardeners have seen side shoots or smaller heads after the first harvest.
What should you not plant next to cauliflower?
Cauliflower does not pair well with strawberries, tomatoes, or other brassicas like broccoli and cabbage. These plants can compete for the same nutrients, attract similar pests, or inhibit each other’s growth.
How many cauliflower seeds should I plant per hole?
The recommended number of cauliflower seeds to plant per hole is 2-3 seeds. Here’s why: Planting multiple seeds improves germination rates in case one fails. Extra seeds allow you to select and retain the strongest seedling after thinning. Spacing seeds 2-3 inches apart reduces root disturbance when thinning later.
How do you plant cauliflower seeds?
Plant 2 seeds in a 1/2 inch deep hole in a starter kit. If planting directly in ground space out 2 feet between each hole. Plant at least 3 seeds per hole for a better chance of growth. Not every cauliflower seed will sprout. They have a 70% germination rate.
How many cauliflower seeds should I plant in a pot?
When starting indoors, sow 2 to 3 cauliflower seeds up to 1/2 an inch deep in small nursery pots or seed starting trays/flats. Keep potting soil evenly moist but not soggy, which could cause seeds or seedlings to rot. If multiple seeds germinate, thin to 1 cauliflower seed per pot/cell.
How deep should cauliflower seeds be planted?
Cauliflower seeds germinate best when sown indoors, planted 1/2 inch (1. 25 cm) deep, and preferably at least 2 to 3 seeds per planting hole and thinning out to one sprout after. You can sow cauliflower directly outdoors (under row covers or plastic), but for best success, you should start your cauliflower seeds indoors and transplant later.
How far apart do you plant cauliflower seeds?
When starting indoors, plant two to three cauliflower seeds in small nursery pots or seed starting trays or flats. Make sure the seeds are about half an inch deep. Keep potting soil evenly moist but not soggy, which could cause seeds or seedlings to rot. If multiple seeds germinate, thin to 1 cauliflower seed per pot/cell. How far apart do you plant cauliflower?.
How do you grow a cauliflower head?
Babying your cauliflower will produce the best head. Water frequently and keep plants well-fertilized. As heads develop, clip leaves together to keep the head snow white. Place cauliflower seeds 2 or 3 per hole or cell. Plant seeds ½” deep. Keep seeds moist until they germinate in 10 to 15 days.