Zinnia Growing Guide: Planting, Care & Harvest

Zinnia elegans

Growing calendar

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

JanFebMarAprMayJunJulAugSepOctNovDec

Sow / plantFlowering

Guides

Common problems

Start from what you can see on the plant.

Wilting Yellow leaves Leaves dying White powder Leaf spots Fruit problems

Pests and diseases (17)

Problems recorded for this plant, most serious first.

Bacterial Wilt

Disease

Leaves wilt while still green during the day and recover in the morning and evening; after a few days of this the plant dies. Cut the stem and stand it in water and a milky white bacterial ooze streams out in threads.

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.

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.

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.

Bacterial Soft Rot

Disease

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.

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.

Gray Mold

Disease

Water-soaked brown lesions form on flowers, fruit and leaves, densely covered by a fuzzy gray mold. Fruit rots and drops, and decay continues in storage after harvest.

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.

Mosaic DiseaseZonate Leaf BlightFusarium Wilt and Damping-offFlower BreakFoliar NematodeLeaf RotAlternaria Black Spot

Written byYasuGrowing vegetables and fruit in Chiba, Japan, and building Gadenin. Corrections are welcome. 15 years of growing.