Callistephus chinensis
Growing calendar
Typical timing for central Japan (Kanto region). Shift it for your own climate, and record your actual dates.
Guides
- Growing Asters from Seed: Sowing Depth, Germination Temperature and Thinning
- Aster Care: Spacing, Summer Water and the Early Summer Cut That Stops the Flopping
- When Do Asters Flower, and Why Is Mine Not Blooming? Timing, Shade and Tired Clumps
- Aster Year Round: A Season by Season Schedule from Spring Division to Autumn Cleanup
- Powdery Mildew on Asters: Why the Lower Stems Go Gray and What Actually Stops It
Common problems
Start from what you can see on the plant.
Pests and diseases (21)
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.
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.
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.
Root Rot
Disease
Fine roots rot brown to blackish brown, growth stops and the lower leaves yellow. The plant wilts easily in the daytime and eventually dies outright.
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.
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.