How to Grow Mustard
Mustard At a Glance
Difficulty
Easy
Category
Herb
Sun Exposure
Full Sun, Partial Sun
Frost Tolerance
Frost Hardy
Cold Hardiness
Survives to -9°C
Plant Family
Brassicaceae
Growing Season
Cool Season
Plant Lifecycle
Annual
How to Start It
★ Recommended for beginners
Mustard handles frost, so sow it in early spring, about 1 to 4 weeks before your last frost, and again in late summer for fall. Sow the seeds 0.5 cm deep, about 2 to 3 cm apart, and cover lightly. They sprout in just 3 to 5 days: thin them (pull the extras so each has room) to 10 cm apart and eat the thinnings in salads.
Mustard is one of the fastest crops you can grow, ready to pick in about 30 days, but hot weather makes it bolt (rush to flower, and the leaves turn tough and very hot). Sow short rows a couple of weeks apart in spring and again in late summer for a steady supply of young leaves. It also makes a good cover crop, a crop you grow to protect and feed the soil, then cut and mix in before it makes seed.
When To Start
First chance to plant
30 Days Before Last Frost
Last chance to plant
30 Days Before First Frost
When should you plant Mustard?
Your planting dates depend on your local climate. Sign up and add your location to unlock personalized dates.
Your Mustard Planting Window
Start planting
May 15, 2026
Last chance
Sep 10, 2026
Your Mustard Calendar
Set your location to turn these into exact dates and reminders.
Sow mustard outdoors now, a short row every 2 weeks
1 week before your last frost· every year
Pick mustard leaves young, before the flower stalks come
30 days after your last frost· every year· optional
Did you water your mustard seedlings today? Keep the top of the soil damp until they are up and growing.
About 1 days after you plant it
Time to thin the mustard seedlings: snip the extras at soil level so each one has room to grow.
About 15 days after you plant it
Your mustard is off to a quick start! Thin crowded seedlings so each plant has room.
About 15 days after you plant it
Harvest time is here! Pick leaves while they are young, before the plant sends up flowers.
About 25 days after you plant it
Picking time may be here: check your mustard.
About 30 days after you plant it
The Journey Ahead
Mustard's Lifecycle
Seedling
Mature Plant
Seed Production
Step 2
Planting & Sprouting
Expect sprouts in 3–5 days
Growing Tips
- 1Grow mustard in full sun in spring and fall, or light afternoon shade if it gets warm.
- 2Mix some compost into the soil before sowing so the leaves grow fast and tender.
- 3Keep the soil evenly moist, because dry soil makes the leaves tough and extra hot.
- 4Water with compost tea every 2 weeks if the leaves look pale.
- 5Cover the bed with row cover right after sowing to keep off flea beetles, tiny jumping beetles that chew small holes in the leaves.
Seedling Phase
Step 3
Growth & Maturity
~30
Days to Maturity
50 cm
Mature Height
25 cm
Mature Width
Pests to Watch For
Diseases to Watch For
Mature Plant
Step 4
Harvesting
Harvest Window
30 days
When to Pick
Harvest leaves or seeds before bolting
How to Harvest
- 1Start picking baby leaves for salads when they are 5 to 10 cm long, or let them grow bigger for cooking.
- 2Cut the outer leaves with scissors and leave the centre to keep growing.
- 3Pick every few days, because once the plant sends up a flower stalk the leaves turn bitter.
- 4Seeds from leaf mustards like Southern Giant Curled can be ground to make your own mustard.
- 5Rinse the leaves and keep them in a bag in the fridge for up to a week.
Step 5
Saving Seeds
How to Save Seeds
Mustard seeds come true as long as the variety is not a hybrid (hybrid F1 seeds will not). Insects carry pollen between plants, so let only one mustard variety flower at a time or keep them about 800 m apart, and remember that mizuna also crosses with turnip, bok choy and napa cabbage. Leave the plants until most pods turn dry and tan, then cut them into a paper bag before the pods split open. Let them dry for a week, then crush the pods and pick out the small round seeds. Store them labelled in a cool, dark, dry place, where they keep about 4 years.
Seed Production
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