Red Giant
Large, deep red-purple crinkled leaves. Striking in the garden and on the plate. Moderately pungent. Good cut-and-come-again productivity.
Fiery Oriental Leaf
Mustard Greens
Brassica juncea
Open the full interactive mustard greens guide →
⚡ Quick start
- Sow 1cm deep in short rows or modules from March
- Cover with insect mesh immediately — flea beetle is the main threat
- Thin to 10cm for cut-and-come-again, 25–30cm for full plants
- First harvest in 3–4 weeks (baby leaves) or 5–7 weeks (full leaves)
- Make a second sowing in August for a frost-hardy autumn crop
🌱 SowMar–May & Aug–Sep (direct or modules)
🌾 HarvestApr–Nov
☀ PositionFull sun or part shade
📐 Spacing10–30cm
DifficultyEasy
⚡ Quick facts
- Difficulty
- Easy
- Crop type
- Hardy Annual (some types biennial)
- Position
- Full Sun or Part Shade
- Soil
- Fertile, Moist, Well-Drained Loam
- Container friendly
- Yes — large containers and raised beds
- Greenhouse recommended
- For earliest spring and latest autumn crops
- Outdoor suitable
- Yes — all UK
- Frost hardy
- Yes — tolerates moderate frost; excellent autumn/winter crop
01 About
Mustard greens are among the fastest and most rewarding brassica leaves you can grow — and one of the most underused in British kitchen gardens. Fiery, pungent, and complex in flavour, they are indispensable in Asian cooking: stir-fried, pickled, braised, or eaten raw in small quantities in mixed salads. They grow rapidly from seed, tolerate moderate frost, and produce generous harvests from spring through to late autumn with just two sowings a year.
02 What to Grow
Mustard greens divide into three broad groups: purple/red types with dramatic colour and strong pungency; green cut-and-come-again types with milder flavour ideal for salad mixes; and frilly/decorative types that combine ornamental value with good eating quality. Choose bolt-resistant varieties for spring sowings and cold-hardy types for the August–September sowing. Leaf size at harvest — baby, semi-mature, or full — dramatically affects flavour intensity.
03 Varieties
The number of varieties shown for each crop is based on UK consumption data (2025/26) — the more popular the crop, the more variety choices we include.
🟣 Red & Purple Types
Bold colour, strong pungency. Excellent for cooking, pickling, and visual impact in salad mixes.
Osaka Purple
Rounded, purple-tinged leaves with a smooth texture. Bold pungent flavour. Excellent for cooking, pickling, and Korean-style preparations.
Ruby Streaks
Finely cut, deep red-purple leaves. Very decorative. Medium heat. Excellent in mixed salad bags and as a garnish.
🟢 Green Mild Types
Milder flavour, faster growing, ideal for salad use and cut-and-come-again harvesting.
Golden Streaks
Finely cut, golden-yellow leaves. Milder than most and slightly sweet. Outstanding in oriental salad mixes. Bolt-resistant.
Green in Snow
Exceptionally cold-hardy. Serrated, bright green leaves. Mild-medium heat. The best choice for the August–September sowing and overwintering.
Green Wave
Vigorous, crinkled mid-green leaves with high yields. Popular for stir-fry and braising. Good summer variety with some bolt resistance.
🌺 Frilly & Decorative Types
Ornamental as well as edible. Excellent for containers, decorative beds, and mixed salad mixes.
Pizzo
Deeply frilled, lacy leaves. Very ornamental in the garden. Medium heat. Popular in continental mixed salad seed collections.
Scarlet Frills
Deeply cut, red-purple frilly leaves. Beautiful and peppery. Excellent mixed with green leaves for visual contrast in salad bags.
Wasabina
Finely cut, mid-green leaves with a distinctive wasabi-like heat. Unique flavour profile. Popular with chefs and for gourmet salad mixes.
04 Where to Source
Mustard greens seed is widely available from online seed companies specialising in oriental vegetables. Named varieties like 'Red Giant', 'Green in Snow', and 'Golden Streaks' are readily found. Oriental salad seed mixes often include mustard greens as a component. Seed is inexpensive and packets contain generous quantities.
🌱 Named variety seed packets
Widely available from online seed retailers specialising in oriental vegetables
🌿 Oriental salad mixes
Often include mustard greens as a component — good for sampling multiple types
📦 Specialist oriental vegetable seed companies
Several specialist retailers online for authentic variety selection
Timing tip: Order seeds in January and February. Popular varieties sell out quickly. Garden centres and markets are a reliable backup from April onwards.
05 Planting Options
🌿 Outdoor Bed
Main production method. Direct sown in prepared beds under insect mesh. Most productive and simplest approach.
- Always cover with mesh immediately after sowing
- Rotate with non-brassica crops on a 4-year cycle
- Water regularly — dry stress triggers bolting and bitterness
- Incorporate compost before sowing for best leaf size and colour
Outdoor Bed — regional timing: Sow direct March–May and August–September
💧 Containers & Raised Beds
Excellent in large containers and raised beds. Good drainage, easier to net against pests, and convenient for kitchen use.
- Use a large container — minimum 30cm deep
- Grow as dense cut-and-come-again for maximum yield from a small area
- Water more frequently than ground-grown plants
- Position near the kitchen for convenient harvesting
Containers & Raised Beds — regional timing: Sow March–May and August–September; pot on as needed
🏡 Greenhouse / Polytunnel
Extends the season significantly at both ends. Particularly valuable for winter production of the hardiest varieties.
- Ventilate well — mustard greens dislike stale air under glass
- Watch for aphid colonies under glass in spring
- Provides frost-free conditions for near year-round cropping
Greenhouse / Polytunnel — regional timing: Autumn sowing September–October for winter harvest; February–March for earliest spring crop
06 Companion Planting
✅ Grow nearby
🌺 Nasturtiums
Trap crop — aphids are drawn to nasturtiums instead of mustard greens. Plant at the bed perimeter.
🌿 Dill
Attracts beneficial insects including hoverflies and parasitic wasps that predate cabbage white caterpillars.
🧅 Celery
Strong celery scent deters cabbage white butterfly. Good intercropping companion between mustard rows.
🧅 Onions
Strong allium scent confuses and deters brassica pests including cabbage white and root fly.
❌ Keep apart
- 🥦 Other Brassicas — Clubroot persists in soil and affects all brassica family crops. Do not grow mustard greens where any brassica has grown in the previous 4 years.
- 🍓 Strawberries — Brassicas are generally poor companions for strawberries and are thought to inhibit their growth and fruiting.
- 🌿 Fennel — Fennel’s allelopathic root secretions inhibit the growth of brassicas including mustard greens.
07 Sowing — How To
🌿 Spring Sowing (March–May)
Prepare the bed
Rake to a fine tilth. Incorporate a balanced general fertiliser if the soil is poor. Mustard greens are not demanding but a fertile soil produces larger, more flavourful leaves.
Cover with mesh first
Lay insect-proof mesh or fine net over the bed before sowing, securing edges firmly. Cut slits to sow through and immediately reseal. Flea beetle arrives within hours of germination in spring.
Sow 1cm deep
Draw a shallow drill 1cm deep. Sow seeds thinly 2–3cm apart. Do not sow densely — the temptation is always to oversow brassica seeds. Cover and firm gently.
Germination in 5–7 days
Germination is rapid at 10–20°C — you’ll see seedlings within a week. Keep the bed moist during germination. Do not remove the mesh.
Thin to final spacing
For cut-and-come-again baby leaves: thin to 10cm. For full-sized plants for cooking: thin to 25–30cm. Use thinnings as microgreens.
First harvest: 3–7 weeks
Baby leaves are ready in 3–4 weeks. Full leaves at 5–7 weeks. For cut-and-come-again: cut to 5cm above the ground; for full leaves: harvest outer leaves working inward.
Mature plant in ground
Full-sized plants develop substantial crowns. In cool conditions they can produce for 2–3 months before bolting. Monitor for signs of flowering and harvest frequency increases as days lengthen.
| Region | Sow / plant | Harvest | Notes |
|---|---|---|---|
| Scotland & Far North | Apr–May | May–Aug | Sow under cover March; direct April–May. Short spring window before summer heat triggers bolting. Harvest June–August. · Apr–May |
| Northern England | Mar–May | Apr–Aug | Sow under cover February–March; direct March–May. Harvest May–August. Bolt pressure increases from June. · Mar–May |
| Midlands & Wales | Mar–May | Apr–Aug | Sow direct from March. Reliable spring harvest April–July. Bolt risk increases in July — summer gap before August sowing. · Mar–May |
| Ireland & Isle of Man | Mar–May | Apr–Aug | Sow March–May direct. Good spring performance. August sowing especially productive in mild Irish climate. · Mar–May |
| South & SE England | Mar–May | Mar–Aug | Earliest sowing February under cover; March direct. Bolt risk from June. Summer gap. Autumn sowing August–September. · Mar–May |
| South Coast & SW | Feb–May | Mar–Aug | February under cover for very early crop. Spring harvest March–June. Autumn sowing very productive in mild autumn conditions. · Mar–May |
❄️ Autumn Sowing (Aug–Sep)
Sow from late July
The August sowing is often more productive than the spring sowing. Shorter days reduce bolt pressure and cooler temperatures improve flavour. Sow from late July in the north; August–September further south.
Cover with mesh against cabbage white
Late summer still brings cabbage white butterfly. Apply insect mesh immediately. Also protects against early flea beetle activity which continues into September.
Sow and thin as spring
Sow 1cm deep, thin to 10–30cm depending on use. The autumn sowing can be grown slightly more densely as bolt pressure is lower.
Harvest September–November
First cut-and-come-again harvest from September. Full leaves from October. Plants withstand moderate frost and continue producing until hard frosts (−5°C).
Winter protection option
Cover with fleece or a polytunnel in October–November to extend harvest into December. "Green in Snow" will survive under fleece through most UK winters and produce fresh leaves in mild spells.
08 Using a Propagator
Heated propagator
Early spring sowings (February–March) benefit from propagator warmth. A heated propagator at 15–18°C produces seedlings in 4–5 days. Remove as soon as seedlings emerge and move immediately to bright light — mustard greens etiolate quickly in warm low-light conditions.
Unheated propagator
An unheated propagator offers limited benefit for mustard greens — they germinate readily at 10°C+ without heat. From March onwards, sow directly into modules on a bright windowsill or outdoors under fleece. Harden off thoroughly before planting out.
Standard unheated propagator — A lidded seed tray traps warmth and humidity around germinating seeds without electricity. Performance depends entirely on room temperature — best placed on a warm windowsill and used from March onwards. Replace the lid promptly after watering. Remove it completely the moment seedlings emerge to prevent damping off.
Windowsill alternative: A bright south-facing windowsill can substitute from late February. Place a clear polythene bag loosely over the pot during germination. Remove immediately once seedlings appear.
09 Soil Requirements
- pH
- 6.0–7.5
- Best
- Loam, Sandy loam
- Tolerates
- Clay loam, Most soils
- Avoid
- Waterlogged, Very acid
💡 Very adaptable and fast-growing. Prefers fertile, moist, well-drained soil. Tolerates poorer soils better than most brassicas.
10 Ongoing Care
🐛 Flea Beetle: The Primary Threat
Flea beetle is the single biggest pest of mustard greens and all brassica-family crops. Tiny black beetles create characteristic small round holes in leaves, can devastate seedlings within 48 hours of germination, and are worst in warm, dry conditions. The only reliable control is fine insect-proof mesh (not netting — the holes must be small enough to exclude beetles) applied before sowing and kept in place through the entire spring period. Biological controls, companion planting, and yellow sticky traps are all secondary measures. Get the mesh on before the seeds go in.
🌱 Managing Bolt Pressure
Mustard greens bolt (run to seed) readily when days are long and temperatures are high — primarily June and July. Once bolting begins, leaf production slows dramatically and flavour becomes aggressively bitter. Delay bolting with three strategies: choose bolt-resistant varieties for spring sowings; harvest frequently — cutting the plant regularly slows the bolting trigger; keep plants well-watered since drought stress accelerates bolting. When plants do bolt, remove them promptly. The August sowing almost never bolts and consistently outperforms spring sowings for total yield.
💧 Watering & Feeding
Mustard greens are not heavy feeders but they do need consistent moisture for the largest, most flavourful leaves. Drought stress causes leaves to become small, tough, and excessively bitter. Water regularly in dry spells — once or twice a week deeply is better than daily light watering. If leaves are pale yellow-green rather than deep green, apply a balanced liquid feed or a top-dressing of blood, fish and bone. The autumn sowing generally requires less feeding as soils are still warm and nutrient-rich after the growing season.
11 Watch Out For
Warning
Mustard greens are a brassica (Brassica juncea) and must be rotated on a 4-year cycle to prevent clubroot buildup in the soil. Clubroot is a devastating soil-borne disease with no cure — affected soil cannot grow brassicas for years. Always cover with fine insect-proof mesh against flea beetle. Do not eat large quantities of raw mature mustard greens in one sitting — they contain glucosinolates which in very large quantities can interfere with thyroid function (cooking deactivates these).
🐛 Insects & pests
- 🦋 Cabbage White Caterpillar — Yellow, ribbed, skittle-shaped eggs in neat clusters on the underside of leaves in summer
- 🐜 Aphids (Blackfly & Greenfly) — Curled, distorted, or stunted growing tips — aphids inject saliva that causes leaf curl to protect them
- 🐌 Slugs & Snails — Silver slime trails on leaves, soil, and pots — often the first sign before damage is found
🍄 Diseases to watch
- 🥦 Clubroot — Clubroot (Plasmodiophora brassicae) is arguably the most feared soil-borne disease in UK kitchen gardens. It persists in the soil as resting spores for up to 20 years — meaning a bed that becomes infected is effectively lost for brassica growing for two decades without extraordinary intervention. Crop rotation is the most critical preventive measure.
- 🔵 Downy Mildew — Downy mildew is caused by oomycetes (water moulds) and is completely unrelated to powdery mildew despite the similar name. It thrives in cool, wet, humid conditions and is most damaging in spring and autumn. Each host plant has its own specific downy mildew species. Lettuce downy mildew can destroy an entire bed within days in the right conditions.
Full identification and treatment advice is in the Pests and Diseases sections.
12 Storage & Preserving
🌱 Refrigerator — Short-Term Fresh
Freshly harvested mustard greens keep well in the refrigerator for 3–5 days. Store unwashed in a loose bag or wrapped in a slightly damp paper towel in the crisper drawer. Wash immediately before use. Young baby leaves are more delicate and last 2–3 days; full mature leaves last up to 5 days. Mustard greens wilt faster than lettuce but significantly slower than watercress. The flavour actually mellows slightly after a day or two in the fridge, which can be an advantage for raw eating.
🍳 Stir-Fry & Cooked Dishes — Best Use of Gluts
Large, mature mustard green leaves are best cooked rather than eaten raw — the heat mellows the fierce pungency to a complex, slightly bitter flavour. Stir-fry with garlic, ginger, and a splash of soy sauce for 2–3 minutes for the classic Chinese preparation (chao jie lan). Also excellent braised in stock, added to soups and ramen, or wilted into curries. Cooked mustard greens can be frozen for up to 2 months — blanch for 1 minute, cool, squeeze out moisture, and freeze in portions.
🧊 Pickled Mustard Greens (Preserved)
Pickled mustard greens, quick-pickled or fermented, are used across East and Southeast Asian cuisines and are one of the most useful ways to deal with a large mustard greens harvest. Follow a tested recipe.
13 Expert Tips
💡 The August sowing always outperforms spring
Many growers focus on the spring sowing and find results disappointing — bolt pressure, flea beetle, and summer heat all work against mustard greens in April–June. The late July to August sowing is almost always more productive: shorter days eliminate bolt pressure, cooler temperatures improve flavour dramatically, flea beetle pressure drops, and plants grow through to November. If you only do one sowing, make it August.
💡 Harvest at the right leaf size for the right use
Mustard greens have three distinct harvest stages with very different flavour profiles. Baby leaves (5–10cm): mild, peppery, excellent raw in salads — best harvested 3–4 weeks after sowing. Semi-mature leaves (15–20cm): medium-hot, good for wilting, stir-frying, or eating raw in small quantities. Full mature leaves (30cm+): very pungent, best for cooking, braising, pickling. The same variety tastes completely different at different sizes. Match the harvest stage to the intended use.
💡 Grow as a dense cut-and-come-again bed for maximum production
Rather than growing individual plants to full size, sow mustard greens densely (seeds 2–3cm apart) and harvest the entire bed at 8–10cm height with scissors — essentially like growing as a microgreen but at a larger scale. The bed regrows 2–3 times. This approach gives you far more harvestable leaf from a given area, reduces the impact of flea beetle (the harvest cycle is shorter), and avoids the bolting problem entirely. Particularly effective for the spring sowing.