Oncidium Alliance (CM Fitch Izumi) Squishy Pseudobulbs: Fungal Rot, Sulphur Treatment, and Repotting

"Squishy" = Active Fungal/Bacterial Rot

Yellowing older leaves = normal. Squishy tissue = emergency. Rot spreads fast in Oncidium alliance.

Emergency Surgery

1. Unpot, remove ALL squishy tissue (cut to firm).
2. Remove affected pseudobulbs entirely if needed.
3. Seal ALL cuts with powdered sulphur or Rootone.
4. Repot in tree fern-based mix (excellent for Oncidium alliance).
5. Smallest pot possible—tight fit.
6. Moss-free mix (compacts, restricts air).
7. Water weekly only for 1+ month to stop disease spread.

Why Tree Fern?

Resists breakdown, maintains aeration, slightly acidic—discourages rot. Ideal for thin-rooted Oncidium types.