Which Plants Produce Toxic Nectar?

It is known that the species of plant honey bees are foraging on, can affect the taste, colour, thickness and fragrance of the honey.  For example, heather produces dark, gelatinous honey.  Oil seed rape can also causes honey to crystallise quickly.

However, it is actually possible for bees to produce honey that is toxic for humans, or to produce honey that is bitter tasting to humans.

Below is a list of plants taken from the research paper: The ecological significance of toxic nectar - Lynn S. Adler (OIKOS 91: 409 – 420. Copenhagen 2000). 

(Please note, some of these plants may be present in your country, or not, but this website receives visits from many different countries).

Plant Species
& Family

Effect on


Aguaria spp. (Ericaceae)

Andromeda spp (Ericaceae)

Kalmia spp.(Ericaceae)

Rhododendron flavum

Rhododendron ponticum

Paullinia australis (Sapindaceae)

Honey toxic to humans

Eckert 1946, Mussen 1979

Azalea pontica

Kalmia latifolia (Ericaceae)

Honey toxic to humans

Kebler 1896

Euphorbia spp. (Euphorbiaceae)

Honey bitter to humans, induced nausea

Pryce-Jones 1942

Arbutus unedo  (Ericaceae)

Honey bitter to humans, induced nausea

Pryce-Jones 1942

Ledum Palustre (Ericaceae)

Honey toxic to humans

Kozlova (1957)

Senecio jacobaea (Asteraceae)

Honey bitter to humans

Deinzer et al. 1977

You might like these

  • Why Babies Can't Have Honey: Honey And Infant Botulism

    Why babies under 12 months old can't have honey (even if cooked). How and why honey can cause infant botulism. When is it okay to give a child honey?

  • Honey And Eczema

    Honey and eczema: Is there any clinical evidence to support the use of honey for treating eczema (atopic dermatitis)? A summary of a number of clinical papers.

  • Honey And Allergies

    Honey And Allergies: Is there a role for honey in treating allergies? Is it possible to have an allergic reaction to honey? A look at the evidence.

Go back to Home page