What are key fall planting steps?
Written by
Kiana Okafor
Reviewed by
Prof. Martin Thorne, Ph.D.Fall cauliflower planting requires the timing to be just right, and plant protection as necessary. Start the seeds when it is cool in late summer so they will not suffer in the heat, and cover with shade cloth if seedlings in trays need protection when temperature exceeds 75°F (24°C). I start my fall crop in mid-July for an October crop: they will be all gathered in before hard frosts arrive.
Timing Strategy
- Count back 10-12 weeks from first expected frost date
- Sow seeds during cooler evening temperatures
- Use soil thermometers to ensure 60-70°F germination range
- Avoid midday sowing when greenhouse temperatures spike
Heat Protection
- Install 30% shade cloth over seedling trays
- Mist seedlings twice daily during heat waves
- Position propagation area for morning sun only
- Use reflective mulch to deflect excess heat
Prepare "phosphorus-rich" soil before transplanting. Prise open planting holes and mix in a touch of bone meal (1/4 cup per plant). This will stimulate strong root growth and make your plants more resilient to cold temperatures. In autumn, I test the pH weekly; rain can affect a soil's acidity. Ideally, levels of 6.5-7.0 should keep nutrients readily available.
Mulching Methods
- Apply 4-inch straw layer after transplanting
- Use dark plastic mulch to absorb daytime heat
- Replenish mulch after heavy rains
- Leave 2-inch clearance around stems
Frost Protection
- Install hoop houses when nights dip below 45°F
- Use thermal row covers rated for 6°F protection
- Place water jugs around plants as thermal mass
- Employ cloches for individual plant protection
Time: transplant 6 weeks to 2 months before frost is expected. This depends on the plant. Harden off seedlings for a week before transplanting outdoors. Choose overcast days for transplanting. I soak seedlings in a seaweed solution before transplanting. This helps strengthen them against cold nights in the fall.
Read the full article: When to Plant Cauliflower: Expert Timing Guide
