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Vegetables

Black Soybean Growing Guide: Planting, Care & Harvest

A soybean type with black seed coats, sown in early summer and left to dry on the plant for autumn harvest and storage.

Black Soybean

Glycine max

Growing calendar

Typical timing for central Japan (Kanto region). Shift it for your own climate, and record your actual dates.

Sow / plantGrowingHarvest

Guides

Common problems

Start from what you can see on the plant.

Pests and diseases (62)

Problems recorded for this plant, most serious first.

Fusarium Yellows

Disease

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.

Fusarium Wilt

Disease

Lower leaves wilt during the day and recover morning and evening, and this cycle repeats as the plant dies back. Cutting the stem reveals characteristic browning of the vascular tissue.

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.

Brown Leaf Spot

Disease

Small light brown to gray-brown spots form on the leaves and enlarge into irregular lesions. When they merge the whole leaf dies and plant vigor drops sharply.

Sclerotinia Rot

Disease

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.

Citrus Melanose

Disease

Tiny dark brown specks are scattered over fruit and leaves, sometimes clustering into tear-streaks or a sandpaper texture. Heavy infection makes the rind rough and badly cuts appearance value.

Rust

Disease

Small raised orange-yellow to red-brown pustules form on both leaf surfaces, then rupture and release powdery spores. Heavy infection yellows the leaves and kills them early.

Southern Blight

Disease

The stem rots at soil level and white silky mycelium spreads over the crown and the surrounding soil surface. Brown sclerotia the size of rapeseed then form and the plant wilts and dies rapidly.

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.

Damping-off

Disease

The stem pinches in at soil level, turning water-soaked to brown and thin, and the seedling topples over. Infection before emergence makes the stand uneven with missing plants.

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.

Brown Rot

Disease

Blossoms brown and die, and round brown lesions on fruit expand rapidly. Grayish white powdery mold forms in concentric rings on the lesion and the fruit finally dries into a hard mummy.

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.

Leaf Spot

Disease

Small round brown to gray-white lesions appear on the lower leaves, the centers turning gray with tiny black specks. As they multiply the leaf yellows and drops early.

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.

Replant DisorderPod BlightWitches' BroomFrogeye Leaf Spot of SoybeanDwarf DiseasePotassium DeficiencyCrinkle LeafPhomopsis RotManganese DeficiencyMosaic DiseaseRhizoctonia Root RotSeed StainMild MosaicSudden Death SyndromeMottle DiseaseCrown BlightRoot Rot DisorderPlant-parasitic NematodesGray Leaf SpotCharcoal RotWhite Root RotFusarium Wilt and Damping-offKernel Brown SpotPurple Seed StainViolet Root RotRugose Leaf MosaicStem CankerStem BlightPhytophthora Stem RotPod RotStunt DiseaseDefoliation DiseaseLeaf ScorchLeaf RotBrown SpeckAscochyta BlightCorky Root RotTarget SpotFusarium Head BlightChlorotic Mottle Virus DiseaseReplant DisorderAnthracnose ScabBlack BlightBlack RootBlack Root Rot

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