Correcting Pale Green Leaves on Corkscrew Willow

Diagnosis: Chlorosis

A 12–14 foot corkscrew willow (Salix matsudana 'Tortuosa') with pale green (not yellow) leaves likely suffers from iron chlorosis—unable to absorb iron in alkaline or compacted soil—despite previous tree-spike fertilization.

Treatment Plan

1. Soil-applied complete fertilizer: Broadcast 1 lb of 13-13-13 per inch of trunk diameter under the canopy (outside 6 inches from trunk) monthly during the growing season until color improves.
2. Iron supplement: Apply chelated iron (Fe-EDDHA) per label—effective in high-pH soils. See Kansas State guide: Iron Chlorosis in Trees.
3. Soil test: Confirm pH and nutrient levels through your local extension service.

Why Tree Spikes Failed

Spikes concentrate nutrients in small zones, often missing the broader root system and not addressing pH-related iron availability.

Comparison Tree

The smaller, lime-green willow likely has a more favorable root zone (better drainage, lower pH, or less competition).