Burying banana peels feeds plants potassium (roses in particular).
Contested
Banana peels do hold some potassium, but a buried fresh peel releases next to nothing until it rots — months away — and can draw pests in the meantime. Compost them instead; if a plant needs potassium, a soil test tells you, and a balanced amendment delivers it now.
What is actually known
A banana peel does contain potassium, but it is locked in undecomposed tissue. Buried whole and fresh it releases almost nothing on any useful timescale — it has to rot down first, which takes months — and meanwhile a shallow-buried peel can attract flies, rodents, and mould. The potassium is real; the "instant fertiliser" delivery is not. Composting it first turns the peel into a genuine slow contribution to organic matter.
Evidence: not yet confirmed against its 1 source.
what this rests on - one pointer
nutrients in undecomposed peel are not plant-available on a useful timescale; extension consensus
When would that grow at your place? →
Cite this page
Milpa Gardens. "Burying banana peels feeds plants potassium (roses in particular)." Evidence grade: Contested. https://milpa.garden/beliefs/banana-peels-banana-peel-fertilizer/
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