Brassica rapa (narinosa group) (Brassicaceae or cabbage family)
Production
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Soil preparation
Tatsoi should not follow after other cole crops.
A soil test will determine how much compost needs to be applied.
Spread lime as needed to increase both the pH and Ca levels. Dolomite lime will also increase Mg levels. Spread gypsum when calcium levels are low but pH is correct.
A fertilizer company can add OMRI-listed potassium sulfate to compost if it doesn’t have enough K to meet the crop’s needs. If this isn’t possible, spread the correct amount of fertilizer and incorporate it before planting.
Test for boron and apply only as recommended by the soil test. A fertilizer company can add boron to compost to optimize boron distribution. If this isn’t an option, distribute soluble boron through a water solution with a sprayer directly on the soil. If applied directly on the crop, don’t exceed more than 1 lb. of boron per acre to avoid leaf burn.
Direct-seeded tatsoi requires a fine and firm seedbed. Prepare the land a few weeks in advance to provide the opportunity for some initial weed control via shallow cultivation or flaming.
Alternatively, place a silage tarp over the prepared and irrigated seedbed 3–5 weeks in advance of the seeding date (depending on the time of year). This will flush many annual weed seeds and reduce weed pressure. Remove the tarp when the weeds have died.
Common recommended fertilizer rates1
Nitrogen
Phosphorus
Potassium
pH
120
0-160
0-200
6.2-6.5
1Rates are for New York and are from Cornell University’s Nutrient Guidelines for Commercial Vegetable Production (2019). Check the Cornell website for updated guidelines, or consult with local experts for recommended rates outside New York.
Greenhouse guidelines
EZ Seeder seeding plate #16
Cell pack tray
Germination temp
Growth temp
Hardening off
Notes
128
65°–75°
65°–75°
Withhold water
Put plug trays on a wire mesh bench to encourage air pruning. Take plants outside 1 week before planting in the field.
Number of successions
Spring: Tatsoi doesn’t do well during hot and dry weather. Plant it in the greenhouse 4–5 weeks before the last frost date. Depending on your markets, plant each week for continuous harvest in spring and early summer. In New York, this is limited to 2–3 successions.
Fall: Tatsoi does best as a fall crop. In New York, seeding or planting is resumed in July on a weekly basis until 4–5 weeks before the first frost, for continuous harvest until November.
Transplant readiness indicators
Plants should come out of their cells easily. Plants should generally not be older than 5 weeks.
Transplanter
Rows
In-row spacing
Planting depth (inches)
Notes
3
5 inches
Normal: The potting medium should be level with the soil.
Water wheel planters can only plant as close as 7 inches, so adjust the in-row distance as needed.
Direct seeding information
Seeder
Rows
Seeds per foot
Seed plate no.
Depth (inches)
Sprocket setting
Notes
Planet Jr.
3-5
22
2
Depth 2
Spreader shoe
Sutton Jr.
9
30
6
1/4
1 mph
Jang
3-5
6
YHJ12 or YX12
Front 14/rear 9 or 10
Cultivation procedures
Use a basket weeder or wheel hoe when weeds are in the white thread stage, without burying the young crop. Weed control is more effective when you eliminate weeds before they emerge.
Hand hoe between plants.
Insect and disease protection
Control black rot (Xanthomonas) by purchasing clean seeds, keeping the greenhouse clean and exposing seed to hot water treatment. Some organic seed suppliers hot treat their seeds, so check with them before applying your own treatment, as double treatment can affect germination.
Cover the crop with floating row covers or insect netting before emergence or after transplanting to avoid flea beetle damage. Keep covered until harvest. Or, use a spinosyn-based product like Entrust.
Fall-planted tatsoi doesn’t need any protection after the third generation of flea beetles, which is around September 1 in the Northeast. If possible, follow Extension bulletins that publish the timing of each generation of flea beetles, or place yellow sticky cards at plant height to monitor their presence. Check the cards at least twice a week.
Spray beneficial nematodes on heavily infected land to control flea beetle grubs and avoid future generations. Flea beetles tend to overwinter in nearby hedgerows and grass strips.
You can prevent cutworms by spraying the soil with the beneficial nematode Steinernema carpocapsae. Once the pest is in the crop, control the population by spraying the crop with Bacillus thuringiensis kurstaki, or spread a baited product containing spinosyn, like Seduce, around the plants.
Cabbage maggots: To reduce infestations of cabbage maggots on young seedlings, cover them with floating row covers or insect netting, as you would for flea beetles. Maggots appear in 3–4 generations in the Northeast, starting in early spring.
Scout for the eggs of imported cabbage worms or diamondback moths on the underside of leaves. When the small worm population is over 2 per plant, spray a Bacillus thuringiensis (Bt aizawai or Bt kurstaki) product, such as XenTari, or a spinosyn-based product, such as Entrust, every week until the population is under control. Alternate your spraying schedule by using Bt products along with a spinosyn-based product to avoid resistance buildup.
Other cultural practices
Irrigate frequently for optimum yield and plant health. Frequency depends on soil type, evaporation, precipitation and the particular needs of the crop.
Double cropping and/or cover cropping
You can plant fall lettuce or spinach after early-planted tatsoi.
You can follow a late tatsoi crop with a cover crop, but don’t incorporate the residue when harvesting in November. This is to avoid winter erosion.
Harvest
Yield
An average of 0.2 lbs. per row foot
Standards
Harvesting1 40 lbs. per person, per hour
Washing 8–10 boxes per person, per hour
Tools and supplies needed
Knives and regular 1 ⅓-bushel boxes
1Harvest rates don't include the time required to transport crops from the field to a wash and pack shed or storage facility.
Ready-to-harvest and quality indicators
Tatsoi is approximately 4–6 inches tall.
Tatsoi is dark green, free from holes and yellow leaves.
Harvest procedures
Wash hands and sanitize knives before harvesting.
Harvest in the morning to avoid field heat accumulation.
One hand holds a small bunch of tatsoi by the top of the leaves. The other hand cuts with a knife in a smooth motion.
You can also harvest tatsoi as a head, the same as bok choy.
Washing procedures
Wash tatsoi at least twice, except when using a passthrough, conveyor-style washer.
Add a sanitizer like hydrogen peroxide and peracetic acid to the water of the first rinse tank. Use the guide How to Wash Produce Using a Peracetic Acid Solution to establish how much sanitizer solution to add to water.
By going through the 2 tubs of cold water the greens stay fresher longer and are very clean.
Don’t leave greens in water for longer than 1 minute. Leaves tend to get waterlogged after a few minutes, which causes them to deteriorate faster.
Dry the loose leaf tatsoi in a centrifuge or salad spinner, but take care that leaves aren’t damaged, as this can cause bacterial decay. There are different sizes and models of commercial-grade salad spinners available through restaurant equipment suppliers.
At 32°–42° and 95–98% humidity. Cover in closed containers or bags if stored for a few days. Tatsoi is highly sensitive to ethylene exposure, which will turn the leaves yellow. Allow for good air exchange and don’t store with crops that release ethylene.
This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture through the Sustainable Agriculture Research and Education (SARE) program. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and should not be construed to represent any official USDA or U.S. Government determination or policy.
