Oxalis yellow leaves

One old leaf can yellow naturally. On Oxalis triangularis, a gradual fade of most leaves with a pause in new growth may be dormancy; yellowing with wet-soft bases points instead to damage.

Growing or resting?

If still producing shoots, check moisture and light. Water a dry root ball and drain, or remove runoff from a wet pot. Inspect underground tissue if yellowing comes with persistent wilt or softness.

If firm rhizomes remain while the top enters rest, follow the false shamrock dormancy steps. Reduce watering as growth stops; fertilizer cannot prevent a normal rest period.