Home » Bee Farm Blog » Bee Gardens » Plants Toxic to Honey Bees (or Humans)

Plants Toxic to Honey Bees (or Humans)

Honey bees have the flowers to thank for most of their food resources.  Gathering nectar and pollen from blooming plants, they store food for later use.  But, not every flower is a good food source for hungry bees. Some plants are toxic to honey bees and may even have nectar that results in poisonous honey.

Rhododendron flowers have nectar that produces poison honey image.

Toxic Nectar Can Result in Poisonous Honey

For the most part, plants and pollinating insects have a symbiotic relationship.  Flowers provide nectar and/or pollen. In return, bee pollination results in the opportunity for more fruit and seeds for the plants.

May contain affiliate links. Read my privacy and affiliate disclosure policy for more info.

Resourceful honey bees gather the very best food resources available at any given time.  This diligence allows them to store vast amounts of honey for Winter survival. 

However, this industrious nature of bees can cause problems in certain conditions. Not every source of nourishment is safe for our colonies.

Common blooming plants that can be poisonous to bees, rhododendron, jessamine, azaleas image.

Poisonous Nectar from Flowers

While pollen from certain plants can be poisonous to honey bee colonies, the largest culprit is nectar.  When this nectar is transformed into honey, it may be toxic to the bees or even humans in some cases.

So, should you be very worried about consuming toxic honey from your bees?  For the most part, no.  It is rare in most locations for the bees to collect enough poisonous nectar to harm themselves or you.

When many of these plants are blooming, other nectar sources are more attractive.  Chances are the bees will not zone in on the bad target plant. 

And some flowers are only a danger during certain environmental conditions, such as a drought.  For most beekeepers these problems are a rare occurrence.

However, it is good to know the identity of plants that can produce nectar toxic to bees. This allows the beekeeper to avoid toxic honey. Feeding the colonies may also be a strategy.

Common Plants that May Be Toxic to Bees

These flowering plants may be poisonous to honey bees – at least under certain conditions.  The beekeeper should not try to eradicate them from the landscape. 

Instead, it is good to be aware and monitor bee activity during droughts, late freezes etc. A couple of them a good honey plants during normal weather conditions.

  • American Basswood (Basswood tilla) – only in times of drought – otherwise excellent source
  • California Buckeye (Aesculus californica) – biggest threat during drought
  • Jimsonweed (Datura Stramonium)
  • Mountain Laurel (Kalmia latifolia)
  • Rhododendron (Rhododendron spp.)-some species
  • Summer Titi (Cyrilla racemiflora)-causes purple brood disease
  • Yellow Jessamine (Gelsemium sempervirens) -Carolina Jessamine
Yellow flowers on Carolina Jessamine is toxic to honey bees image.

Nectar Dilution Affects Toxicity of Poisonous Plants

As with many living things, the degree of toxicity for poisonous nectar is often related to dosage.  During a normal season with good foraging conditions, bees choose other nectar sources.

In the case that some of the foraging workers do visit poison plants, the nectar will be diluted back in the hive.  As it is mixed with nectar from thousands of other flowers, it becomes less harmful to the colony.

Jimson Weed blooms can poison colonies of bees image.

Are These Nectar Sources a True Danger?

Most beekeepers will never experience a problem with plants killing their bees.  My water gardens provide a water source for my bees.  The Pitcher Plants, Sundews and Venus Fly Traps are designed to attract and trap insects.

Yet, it is rare for me to find a dead honey bee inside any of them.  Plenty of ants and gnats but very few bees.

Rhododendron and Mountain Laurel grace the hillsides of this region.  Only once in many years have I seen bees working those blossoms.  But you will hear of years where a very late freeze killed many of the early Spring blooms.

Beekeepers in areas just north of here did experience some “Mountain Laurel Honey”.  The bees were fine for the most part and the beekeepers as well to the best of my knowledge.

As with some other aspects of beekeeping, this is where knowing local beekeeping conditions comes in handy.  Learn the nectar sources in your region, which flowers do bee like and when do they normally bloom.

A Final Word About Poisonous Nectar or Toxic Honey

There is no need to run outside and rip your Rhododendron and Azaleas from the landscape.  In most cases, your bees will ignore the blooms.  Choosing instead to forage on better nectar sources. 

When there have been reports throughout history of humans being sickened by consuming toxic honey, this seems to be a very rare occurrence.

It is the wise beekeeper who understands foraging conditions and is observant of environmental factors that can change each year. Giving him/her a heads up on plants toxic to honey bees.

Similar Posts