Gadenin日本語Get the app
Brassica rapa var. pekinensis
Growing calendar
Typical timing for central Japan (Kanto region). Shift it for your own climate, and record your actual dates.
Guides
- When to Sow Napa Cabbage So It Heads Before the Cold
- Planting Out Napa Cabbage: Spacing, Soil and the First Two Weeks
- Why Napa Cabbage Will Not Form a Head, and How to Fix It
- Napa Cabbage Growing Schedule From Sowing to Harvest
- Napa Cabbage Pests and Problems: Flea Beetles, Slugs and Tip Burn
- How to Tell When Napa Cabbage Is Ready to Cut and How to Store It
Common problems
Start from what you can see on the plant.
Pests and diseases (39)
Problems recorded for this plant, most serious first.
Sclerotinia Rot
MajorDisease
The crown, stem or head rots in a water-soaked way and is covered in white cottony mycelium. Black sclerotia later form inside and on the surface, and the plant wilts and dies.
Bolting
MajorDisorder
A flower stalk rises from the center of the plant and the leaves turn tough and stringy, spoiling eating quality. Heading vegetables run to seed without ever forming a head.
Bacterial Soft Rot
MajorDisease
The crown or the head becomes water-soaked and soft, then collapses into a slimy mush. The rotting tissue gives off a distinctive foul odor.
Clubroot
MajorDisease
Leaves wilt during the day and recover morning and evening, and growth is markedly poor. Pull the plant and the roots carry many spindle-shaped or irregular galls.
Cabbage Armyworm
MajorPest
Young larvae feed in groups on the leaf underside, eating only the tissue so the leaf turns translucent white. Larger larvae chew big holes and can strip a plant bare in a single night.
Cabbage White Caterpillar
CommonPest
Irregular holes appear in the leaves and eventually only the veins remain. Dark green pellets of frass are conspicuous at the crown and on leaf undersides.
Black Rot
CommonDisease
V-shaped yellowing spreads inward from the leaf margins and the veins darken into a black network. As it advances the whole plant wilts and dies.
Diamondback Moth
CommonPest
Larvae graze the leaf tissue from below, leaving the upper skin as white window-like patches. As they grow they chew many small holes and also attack the growing point.
White Rust
CommonDisease
Creamy white slightly raised irregular pustules form on the leaf underside and burst through the skin releasing white powder. The upper surface turns pale yellow and heavy infection ruins appearance and market value.
Excess Nitrogen
CommonDisorder
Leaves are large and dark green and stems grow thick but soft. Flowering and fruit set decline while aphids and disease become more frequent.
Slugs
CommonPest
Irregular holes are chewed in leaves and fruit with glistening slime trails nearby. By day they hide under pots and bricks or in dead leaves at the base of the plant.
Cutworms
CommonPest
Typically a newly transplanted seedling is severed at soil level and found toppled the next morning. Scratch the soil beside the cut seedling and a gray-brown caterpillar turns up.
Fusarium Yellows
OccasionalDisease
Yellowing starts on the lower leaves, the petioles twist and the plant leans to one side. Vascular tissue browns, growth stops, and heading vegetables may die without ever forming a head.
Powdery Mildew
Disease
White patches appear scattered on the upper leaf surface at first, then the whole leaf is coated in a white powder. Leaves later yellow, brown and die back, and reduced photosynthesis cuts growth and yield.
Anthracnose
Disease
Light brown to dark brown round lesions with sharp margins form on leaves and fruit, slightly sunken in the center. In wet weather salmon-pink slimy spore masses ooze out on the lesions.
Onion Thrips
Pest
Fine white stippled scars run in vertical lines along the leaf surface, and the whole leaf eventually turns whitish. Growth stops and both yield and quality suffer.
Root-lesion Nematode
Pest
Elongated blackish brown necrotic lesions form on the root surface and fine roots rot away. Above ground the stand is uneven and plants stay small with pale foliage.
Root-knot Nematode
Pest
The plant wilts in the daytime and does not recover with feeding or watering. Pull it up and the roots carry beaded chains of galls of varying size with few fine roots.
Verticillium Wilt
Disease
Only one side of the lower leaves yellows and wilts, and the symptom moves up the plant. Stem vascular tissue turns pale brown and the plant dies without ever growing well.
Bacterial Spot
Disease
Small water-soaked spots appear on the leaves, later turning brown with yellowing around them. Fruit develops water-soaked or scabby spots from which rot spreads.
Downy Mildew
Disease
Pale yellow to yellow-brown angular lesions form on the upper leaf surface with a gray-purple mold in the matching spot underneath. Lesions merge, the leaves die back and the plant declines early.
Ring Rot
Disease
The bark of branches and trunk becomes rough and warty, serving as the inoculum source. Fruit develops round brown lesions that soften and rot in concentric rings.
