How to Grow Broccoli — Any Climate
How to grow broccoli anywhere in the world, without a calendar: wait for a soil temperature, not a date. Broccoli is a cool-season crop. Start indoors 4-6 weeks before your last frost date; direct sow again for a second, cooling-conditions crop. Give them full sun, space them 45 cm (18 in) apart, and allow 50-80 days to maturity. These thresholds hold in any climate and either hemisphere.
When to plant broccoli — the conditions to wait for
There is no universal date for broccoli, because the same calendar month means completely different things at different latitudes and in opposite hemispheres. What does not change is the set of conditions the plant responds to.
| Condition | What this crop needs |
|---|---|
| Temperature class | Cool-season |
| When conditions are right | Start indoors 4-6 weeks before your last frost date; direct sow again for a second, cooling-conditions crop |
| Light | Full sun |
| Spacing | 45 cm (18 in) apart |
| Germination time | 5-10 days |
| Days to maturity | 50-80 days to maturity |
Observe, measure, decide
- Observe. Watch what your own garden does, not what a calendar says. When does standing water disappear in spring? Where does frost linger longest? Which corner warms first? A season of notes beats any regional average.
- Measure. Two instruments settle almost every timing question: a soil thermometer pushed 5-10cm (2-4in) into the bed at the same time each morning, and your own records of first and last frost. Soil temperature is the number that actually governs germination.
- Decide. Match the measurement to the crop's temperature class, then count backwards from your frost date using days-to-maturity. If the arithmetic does not fit your season, change the cultivar or the crop — not the date.
💡 The one instrument worth owning
A soil thermometer pushed 5-10 cm (2-4 in) into the bed, read at the same time each morning, answers more timing questions than any calendar. Soil temperature — not air temperature — governs whether seed germinates or rots.
Soil and site
Fertile soil, pH 7.0-7.2 — a critical cultural control against clubroot.
Watering
Consistent moisture; tolerates light frost well.
Spacing and layout
Space broccoli 45 cm (18 in) apart. Crowding is the most common cause of disappointing yields — plants compete for light and water, and poor airflow between them raises disease pressure sharply.
Companion planting
Thyme, onion (strong evidence — scent masking measurably cuts cabbage loopers and flea beetles in field trials).
Common problems
Cabbage looper, imported cabbageworm and flea beetles are near-universal threats — floating row cover from transplant, or Bacillus thuringiensis (Bt), controls them without chemicals.
Turn growing broccoli into a written plan. The Global Vegetable Garden Planner (printable PDF) has the soil-temperature reference, crop rotation planner, sowing log and harvest tracker — 73 pages, no calendar required.
Frequently Asked Questions
When should I plant broccoli?
Wait for conditions rather than a date. Start indoors 4-6 weeks before your last frost date; direct sow again for a second, cooling-conditions crop. This works identically in either hemisphere.
What temperature do broccoli need?
They are a cool-season crop. Germination takes 5-10 days once conditions are right.
How far apart should broccoli be planted?
Space them 45 cm (18 in) apart.
What usually goes wrong with broccoli?
Cabbage looper, imported cabbageworm and flea beetles are near-universal threats — floating row cover from transplant, or Bacillus thuringiensis (Bt), controls them without chemicals.
Last updated 25 August 2026
Tools That Help With This Crop
Use these links when the guide moves from reading into sowing, planting, watering, and keeping the crop healthy.
Plan the next step
Use the printable SoilCommander planner for your region to turn this guide into sowing dates, bed layouts and weekly garden tasks.