Why did my broccoli skip making a head and go straight to flowers?
Broccoli bolts when it experiences heat or stress during head formation — once it starts flowering, the head is unsalvageable, but timing adjustments can prevent it next season.
Broccoli is a cool-season crop that needs to form its head (the edible dense bud cluster) before temperatures rise above about 80°F. When the plant experiences heat while trying to form a head, it accelerates through the process and opens its flowers in days rather than weeks. You may see a head that looks like it's developing, then suddenly spreads open and turns yellow with tiny flowers. That plant is done for the season.
Timing is the main lever. For a spring crop, broccoli transplants ideally go out 4–6 weeks before your last frost — early enough to form a head while temperatures are still cool. Starting too late means the heads try to develop in increasingly warm weather. In climates where spring heats up quickly, fall broccoli is often more successful: start seeds 10–12 weeks before your first fall frost and transplant when summer heat is breaking.
Variety matters too. Days-to-maturity varies widely between broccoli varieties. A fast-maturing variety (50–55 days) may be more appropriate for a short spring window than a slower one (70+ days). Heat-tolerant varieties exist and are worth seeking out for spring planting in warm climates.
A broccoli head that has barely started to open with a few yellow flowers is past its prime but not worthless — the flavor is stronger and more bitter, but it's still edible. Harvest it immediately, use it in cooked dishes, and cut the main stem back. Many varieties will produce small side shoots after the main head is harvested, and these often develop better in the cooling days of late summer or early fall.
- Blossom DropFlowers fall before setting fruit, often during temperature extremes or after weather stress.
- Gray Mold (Botrytis)Gray-brown fuzzy mold on fruit, flowers, or stems — soft, collapsing tissue beneath the coating in cool, wet conditions.
- Brown Marmorated Stink BugSunken, corky dimples on fruit and pods caused by a mottled brown shield bug feeding through the skin.
- Cabbage MaggotBrassica transplants wilting and dying as white maggots tunnel through roots at or below the soil line.
- Carrot Rust FlyRusty tunnels through carrot and parsnip roots made by small white maggots feeding inside the root.
- When should I start seeds indoors?Count backward from your last frost date using the seed packet's weeks-to-transplant number — most tomatoes and peppers go in 6–8 weeks before last frost.
- My tomatoes wilt every afternoon in hot weather — is something wrong?Midday wilt on hot days is often a normal, temporary response to heat load — if plants recover by evening, the roots are functioning and the wilting is a water conservation mechanism, not distress.
- How can I extend my growing season in fall?Row cover fabric, cold frames, and switching to cold-hardy crops are the three most reliable tools for extending production 4–6 weeks past your first fall frost.