Narcissus deters voles and rodents.
A good hunch · suboptimal if ignored → advise
How it works
Narcissus bulbs and tissue contain lycorine and related alkaloids, which are toxic to eat. Rodents avoid them accordingly — field mice rarely touch daffodils even where they readily eat tulips and crocus — so a ring of narcissus tends to be left alone rather than gnawed. It is an avoidance effect, not a barrier: it discourages feeding on the bulbs, not a guarantee against every rodent.
The evidence
Evidence: confirmed against 3 sources in the research-based literature.
the 3 sources
Univ. of Illinois Extension, 'Bulbs', extension.illinois.edu/flowers/bulbs (read 2026-07-11): field mice 'most often attack tulips, crocus and gladioli and rarely eat daffodils, alliums or colchicums.'
Univ. of Illinois Extension, 'Knowing poisonous plants can save a life', extension.illinois.edu/blogs/know-how-know-more/2022-07-05-knowing-poisonous-plants-can-save-life (read 2026-07-11): 'Daffodil, hyacinth, and narcissus contain the toxin lycorine, which, if eaten, typically causes nausea.'
Clemson HGIC, 'Planting Deer Resistant Bulbs', hgic.clemson.edu/planting-deer-resistant-fall-bulbs (read 2026-07-11): daffodils 'are also poisonous, so deer are not tempted to eat them.'
Plants this fires on
Change history
Every change to this rule is one commit. This is what the project's version history records — the date and the reason — not a summary of it.
- narcissus deters voles/rodents — fill the stub mechanism
- promote to verified — Narcissus deters voles/rodents
- cite Illinois + Clemson for narcissus rodent deterrence (rule confirmed)
Cite this page
Milpa Gardens. "Narcissus deters voles and rodents." Evidence grade: A good hunch. https://milpa.garden/rules/narcissus-deters-voles-rodents/
A garden-planning corpus: every claim states its evidence grade and links its sources on the page. Cite it with the grade, and add the date you read it.