How to Grow Brussels Sprouts — Any Climate
How to grow Brussels sprouts anywhere in the world, without a calendar: wait for a soil temperature, not a date. Brussels Sprouts are a cold-hardy crop. Start indoors 6-8 weeks before your last frost date — needs the longest season of any common brassica. Give them full sun, space them 60 cm (24 in) apart, and allow 100+ days to maturity; sweetest after a frost. These thresholds hold in any climate and either hemisphere.
When to plant Brussels sprouts — the conditions to wait for
There is no universal date for Brussels sprouts, 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 | Cold-hardy |
| When conditions are right | Start indoors 6-8 weeks before your last frost date — needs the longest season of any common brassica |
| Light | Full sun |
| Spacing | 60 cm (24 in) apart |
| Germination time | 5-10 days |
| Days to maturity | 100+ days to maturity; sweetest after a frost |
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 to help suppress clubroot. Soil must be firm — loose soil produces open, "blown" sprouts.
Watering
Maintain consistent soil moisture, especially during sprout formation.
Spacing and layout
Space Brussels sprouts 60 cm (24 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
Marigold, rosemary, thyme — all help deter the same pests as other brassicas.
Common problems
Same pest pressure as broccoli and cabbage. The longest-season common brassica — confirm your growing season comfortably exceeds 100 days before choosing it.
Turn growing Brussels sprouts 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 Brussels sprouts?
Wait for conditions rather than a date. Start indoors 6-8 weeks before your last frost date — needs the longest season of any common brassica. This works identically in either hemisphere.
What temperature do Brussels sprouts need?
They are a cold-hardy crop. Germination takes 5-10 days once conditions are right.
How far apart should Brussels sprouts be planted?
Space them 60 cm (24 in) apart.
What usually goes wrong with Brussels sprouts?
Same pest pressure as broccoli and cabbage. The longest-season common brassica — confirm your growing season comfortably exceeds 100 days before choosing it.
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.