Asian greens are a diverse group of leafy vegetables most prevalent in Asian cooking. In order to simplify this category we have included Chinese & Savoy cabbages, Pac choi, and mustards. Asian greens can be grown directly from seed or purchased as transplants. Generally, Pac choi and mustards are easier to grow than cabbages. All Asian greens prefer cooler weather, mustard greens even survive through winter with minimal protection.
Asian greens require full to part sun, at least 5‐6 hours of direct sun, and well‐drained soil. Prepare the planting area by mixing 2‐3” of composted manure and lime into the top 4‐6” of the soil. In addition, mix in an all‐purpose granular fertilizer and lime in the bottom of each planting row. Asian greens are also excellent in containers at least 8” deep.
Start seeds for Pac choi and Chinese and Savoy cabbages indoors February through March, 6‐8 weeks before desired transplanting date. Harden off seedlings to outdoor temperatures by setting them in a cold frame for a week before planting. If you do not have a cold frame, set seedlings outdoors in the day and indoors at night for a week before planting.
Transplants can go into the garden as early as two weeks before the last frost date (April 15th in Portland). Plant cabbage seedlings 12‐18” apart in rows 18‐36” apart, and water in with liquid seaweed or B1. Cover your new planting with floating row cover to prevent attacks from cabbage loopers, aphids and other chewing insects that love Asian greens.
Asian greens can be directly sown in your garden March through early June in the Portland area. Be sure to amend planting area with 2‐3” of composted manure before sowing seeds. Plant seeds 1⁄4” deep in rows 18‐ 36” apart. Seedlings should be thinned 12‐18” apart when they have at least two true leaves.
Seeds for a fall harvest should be started in flats in July and August. Seedlings can go in the ground once they have 2‐3 sets of true leaves. Fall harvested greens can be directly seeded August through September. Asian greens are very sensitive to heat, so plant in the shade of larger summer crops such as cucumbers or potatoes.
Transplants for leafy Asian greens can go in the ground through mid September.
How much to water your plants will require depends on the soil and weather. Water new transplants daily, or when the top 2” of the soil is dry. Once they reach 12” Asian greens need average, evenly moist soil. Avoid overhead irrigation, instead use drip or flood irrigation or hand watering. Mulch around plants to retain soil moisture.
The cabbages are heavy feeders and benefit from a side dressing of composted manure or all purpose granular fertilizer two weeks after transplanting. Repeat side dressing once a month for the next two months. The leafier greens,Pac choi and mustard, benefit from a foliar spray of liquid fish emulsion every 3‐4 weeks.
Chinese cabbages are ready to harvest when the head is firm. Start checking when the heads reach about 12”. Leafy greens such as mustards and Pac choi are ready to harvest about one month after transplanting. You can pick outer leaves to maintain a continual harvest, or cut entire clump about 1” above the ground and wait another month for a second harvest of smaller clumps.
Heads of Chinese cabbage can be stored refrigerated for 7‐14 days to harvest. Leafy greens are best eaten fresh, but will store 2‐5 days refrigerated.
Some problems that can occur with Asian greens are due to weather and cultural conditions. Plants will bolt (go to flower) quickly in reaction to hot weather and drought. Correct planting time, moderate and consistent moisture, soil amending, and row covers are all strategies to improve growing conditions.