Petasites japonicus
Growing calendar
Typical timing for central Japan (Kanto region). Shift it for your own climate, and record your actual dates.
Guides
- Planting Fuki (Butterbur): Where to Put a Plant That Wants to Take Over
- Growing Fuki: Watering, Feeding and Keeping the Colony in Bounds
- Fuki Growing Calendar: What to Do From Flower Buds to Winter Dormancy
- Fuki Pests and Problems: Slugs, Leaf Scorch, Crown Rot and Escaped Rhizomes
- Harvesting Fuki Stalks: When to Cut, How to Peel, and Why You Must Boil It
- Propagating Fuki from Rhizome Divisions: Timing, Cutting and Containing New Plants
Common problems
Start from what you can see on the plant.
Pests and diseases (18)
Problems recorded for this plant, most serious first.
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.
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.
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.
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.
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.
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.