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Komatsuna 'Carlton' F1 HybridBrassica rapaJapanese Mustard Spinach

Just £2.69

Hardy Annual
What is Hardy Annual?
A plant that completes its entire life cycle (growth, reproduction, death) in one season.
Capable of withstanding outdoor winter temperatures down to -15C.

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Description Sowing More Info Delivery
One of Japan's best kept secrets! Vigorous and easy to grow, this Oriental vegetable can be picked as baby leaves in as little as 25 days, or left to grow on for tall, leafy heads of up to 200g (7oz), in just 60 days from sowing. With excellent heat and frost tolerance, Komatsuna 'Carlton' can be grown all year round, withstanding British summers well and making a superb greenhouse crop for winter and spring cultivation. These tasty Komatsuna leaves have a mild Brassica flavour and are delicious steamed, stir-fried, or enjoyed raw in salads. Height and spread: 25cm (10").

Useful Links:
How to grow vegetables from seed
Reasons to buy your seeds from Thompson & Morgan

Patio, Kitchen Garden, Greenhouse


Full sun, Sun or semi shade

Up to 25cm (9.8in)

Up to 25cm (9.8in)

Easy for all

Easy for all

Sowing Months Harvest Months

Japanese mustard spinach must be kept well watered throughout the growing period to reduce bolting and prevent flavour loss. Harvest young komatsuna leaves as required, picking only a few leaves from each plant. Alternatively allow heads to mature and harvest the entire plant as you would cabbage. If flower buds appear pinch them out to prolong cropping.

Direct sow komatsuna seeds from April to September outdoors or October to March under glass, into well prepared, moist, well drained soil in sun or semi shade. Sow seeds thinly at a depth of 12mm (1/2 in) in drills 35cm (14") apart in soil which has been raked to a fine tilth. When large enough to handle, thin komatsuna seedlings to 10cm (4") apart for 'baby salad' leaves, 20cm (8") apart for larger plants or 30cm (12") apart for fully mature plants.

Alternatively sow komatsuna seeds singularly in module trays filled with good quality, moist seed-sowing compost. Place in a propagator or seal container inside a plastic bag at a temperature of 15-20C (59-68F) until after germination which usually takes 7-14 days. Once germinated, grow komatsuna plants on in cool conditions until all risk of frost has passed and they are large enough to plant outdoors at a distance of 30cm (12") apart. Water the plants thoroughly after planting. Sowings made in late summer will continue cropping into winter if protected by cloches, or if sown in frames, under glass, or in pots on the windowsill.


Seeds and garden supplies will normally be delivered within the time period stated against each product as detailed above. Plants, bulbs, corms, tubers, shrubs, trees, potatoes, etc. are delivered at the appropriate time for planting or potting on. Delivery times will be stated on the product page above, or in your order acknowledgement page and email.

Orders for packets of seed incur a delivery charge of £1.95.

Orders which include any other products will incur a delivery charge of £4.95.

Where an order includes both packets of seeds and other products, a maximum delivery charge of £6.90 will apply - regardless of the number of items ordered.

Large items may incur a higher delivery charge - this will be displayed in your shopping basket.

Please see our Delivery page for further details and details of any surcharges that may apply to certain destinations.

Satisfaction Guaranteed

For your complete peace of mind, our Home and Garden products may be returned to us within 30 days of purchase for a refund of the purchase price. Items must be returned unused, at your cost and in mint condition. All items carry a manufacturer's 12 month defects warranty.