Broccoli sprouts are quick to grow indoors and need very little space. With suitable seed, a clean sprouting jar, drinking-quality water and good drainage, you can usually harvest a fresh batch in around 5–6 days.
This simple method uses a jar sprouter and follows the current OzSprout recommendations for broccoli sprouting seed.
What You Need
- Approximately 2 tablespoons (about 20g) of Broccoli Sprouting Seeds
- A clean 500–650ml sprouting jar
- A fine-mesh sprouting lid or suitable draining screen
- Clean, drinking-quality water
- A bowl or drip tray to catch drainage water
A purpose-designed Glass Sprouting Jar makes it easier to soak, rinse and drain the sprouts in the same container.
1. Clean the Sprouting Jar
Wash your hands, jar, lid and any utensils thoroughly before starting.
Reusable sprouting equipment should be cleaned after every crop and allowed to dry completely before storage or reuse.
Starting with clean equipment is especially important because sprouts are normally eaten at a very young stage and the warm, moist growing conditions can also support bacterial growth if contamination is present.
2. Rinse & Soak the Broccoli Seeds
Add approximately 1.5 tablespoons (about 15g) of dry broccoli sprouting seed to a 500ml jar.
Rinse the seed thoroughly with clean water, then cover generously with fresh water and soak for approximately 4 hours.
Avoid overcrowding the jar. Broccoli seeds expand considerably as they germinate and need enough room for effective rinsing, drainage and airflow.
3. Drain Thoroughly
After soaking, drain all of the water from the jar.
Rinse the seeds again with fresh water and drain completely.
Position the jar at a downward angle so excess water can continue to escape while air circulates around the developing sprouts.
Do not leave the seeds sitting in standing water between rinses.
4. Rinse & Drain 2–4 Times Daily
Rinse the sprouts approximately 2–4 times each day, depending on temperature and growing conditions.
Morning and evening rinses are a practical minimum, with additional rinsing useful during warmer conditions.
After every rinse:
- Drain the jar thoroughly.
- Return it to an angled draining position.
- Keep the opening clear so air can circulate.
- Keep the jar away from hot direct sunlight.
During the first few days the seeds will produce small white roots and shoots. Fine white root hairs may become visible around healthy roots and can sometimes be mistaken for mould. Root hairs usually become much less visible immediately after rinsing.
5. Green & Harvest the Broccoli Sprouts
As the cotyledons begin to open, move the jar into bright indirect light for a short period to encourage a greener colour.
Avoid prolonged direct sunlight or excessive heat.
Broccoli sprouts are typically ready to harvest after approximately 5–6 days, depending on temperature and growing conditions.
Give the finished sprouts a final thorough rinse and drain them as completely as possible before refrigeration.
Tips for Growing Broccoli Sprouts Successfully
Keep the Jar Well Drained
Good drainage is one of the most important parts of jar sprouting. The seeds should remain hydrated without sitting in excess water.
Maintain Good Airflow
Avoid sealed cupboards, hot laundries or other stuffy locations. Keep the sprouter somewhere with reasonable airflow and a stable indoor temperature.
Use Clean, Cool Drinking-Quality Water
There is no need to use warm water to speed germination. Clean drinking-quality water is more important than trying to force faster growth.
Do Not Overfill the Jar
Too much seed restricts airflow and makes thorough drainage more difficult. Approximately 1.5 tablespoons per 500ml jar is a practical starting quantity for broccoli.
Want a Continuous Supply?
If you regularly eat broccoli sprouts, stagger two jars by starting the second batch a few days after the first. The Broccoli Sprout Grow Kit includes two glass jars, making staggered batches easier to manage.
Video: Dr Rhonda Patrick – How to Grow Broccoli Sprouts
For a visual demonstration, Dr Rhonda Patrick's FoundMyFitness broccoli-sprouting video covers the basic equipment, preparing and rinsing the seed, harvesting and storing sprouts, along with important food-safety considerations.
Broccoli Sprout Food Safety
Raw sprouts require particular care because the warm, humid conditions used for germination can also allow harmful bacteria to multiply if contamination is present.
The NSW Food Authority advises that sprouts can be contaminated with bacteria including Salmonella, Escherichia coli and Listeria. It also notes that even highly hygienic growing conditions cannot guarantee bacteria-free sprouts.
For safer home sprouting:
- Wash your hands before handling seed or sprouts.
- Use clean equipment and drinking-quality water.
- Drain thoroughly after every rinse.
- Do not allow sprouts to sit in standing water.
- Refrigerate harvested sprouts promptly.
- Discard sprouts that become slimy, unusually discoloured or develop a sour or musty smell.
People at greater risk from food poisoning—including pregnant women, young children, some older people and people with weakened immune systems—should follow current Australian food-safety guidance and avoid raw or lightly cooked sprouts.
Common Broccoli Sprouting Questions
How long do broccoli sprouts take to grow?
Broccoli sprouts are usually ready in approximately 5–6 days, although temperature and growing conditions can affect timing.
Do broccoli sprouts need darkness?
No. They need little light during early germination, but complete darkness is not required. Bright indirect light towards the end of the growing period can help the cotyledons develop a greener colour.
How often should broccoli sprouts be rinsed?
Rinse and drain approximately 2–4 times daily. Thorough drainage after each rinse is just as important as the rinsing itself.
What is the white fuzz on my broccoli sprouts?
Fine white growth evenly surrounding individual roots is often normal root hair development. Root hairs usually become much less visible after rinsing.
Mould is more concerning when growth appears in irregular patches and is accompanied by slime, deterioration or an unpleasant or musty smell. If you are unsure, discard the batch.
Can I use ordinary garden broccoli seed?
Do not automatically use garden seed for edible sprouts. Seed intended for sprouting should be suitable for that use and should not be chemically treated or coated in a way that makes it inappropriate for consumption.
Want to Learn More About Broccoli Sprouts?
For nutrition, sulforaphane, storage, troubleshooting and answers to other common questions, see our complete broccoli sprouts guide.
