I am sure you have seen the memes on social media; Dandelions are the first food for bees. “Don’t pick dandelions and save the honey bee”. How important are these dandelions to bees, and which bees are we talking about? Is it their first food? Do bees actually use the pollen and nectar from dandelions?
Just because social media says its true, does not mean it is. Lets uncover the truth behind this new craze to save the dandelions.
Bees First Food
I grow a lot of plants in my garden and I seem to remember many things flowering before dandelions (Taraxacum officinale). I spoke to one of the researchers at the Honey Bee Research Center, University of Guelph and asked him about the bees first food.
Around here, zone 5, Ontario, “their first important food source is tree pollen. Long before flowers become important, honey bees are in the top of trees collecting pollen. Maples, elms, poplars and willows are important as a first food” and they flower before dandelions.
“They gather dandelion pollen when other pollen is not available.”
Some trees are wind pollinated and produce a lot of pollen. They also have a very concentrated source which means bees don’t have to fly long distances between flowers to get it.
What about herbaceous plants?
Lots of things bloom before the dandelion. This year I kept a record of early flowers in my garden and got help from people on our Garden Fundamentals Facebook Group, who also contributed to the list. All of these flowered before dandelions.
- Snow drops
- Japanese Butter Bur
- Winter aconites
- Vinca minor
- Iris reticulata
- Erica (Heath)
- Spring beauty
- Anemone blanda
- Corydalis solida
- Virginia bluebells
It is clear that dandelions are not a bees first food.
Fruit Trees vs Dandelions
Last spring I found a field of dandelions, and right beside it was a row of flowering ornamental pears. Thousands of flowers on both plants, all in prime condition, on a nice warm, sunny day.
Where were the bees and other insects?
Almost none were on the dandelions. The pears were covered with insects and you could hear the hum they made several feet away. I found a wide range of insects; different kinds of bees and flies, including honey bees. You would think that in such a crowded environment some would go to the dandelions where there was no competition, but that was not happening.
But the story is more complex. Dandelion flowers produce peak pollen between 10:00 and 11:00 A.M. (between 8 and 14C) and close in the afternoon. Apples (don’t have numbers for pears) produce peak pollen between 12:00 and 4:00 P.M.. So it is possible that you might find bees on the dandelions in the morning and on the fruit trees in the afternoon. I can’t remember what time I was there?
There is also evidence that once a bee is conditioned to dandelions, or any other flower, they will stick to sourcing pollen from it for a few days. Even if fruit tree pollen is available, they ignore it, once conditioned on dandelion pollen. An abundance of dandelions may in fact keep bees from the fruit tree pollen, which is a more nutritious source of pollen.
Do Bees Use Dandelions?
Bees do use dandelions for both nectar and pollen. They especially like a lawn that is full of them since this makes it easy for them to collect a load of pollen. According to the Honey Bee Research Station, it is not a preferred food, but it does help fill the gap when other sources are not available and in spring dandelions exist in abundance.
Quality of Dandelion Pollen
“Honey bee foragers collect nectar, pollen, and water from flowering plants. Pollen is the honey bees only significant source of protein, lipids, minerals, and vitamins, all of which are necessary for brood‐rearing, normal development, and worker longevity.” Nectar is a source of carbohydrate that provides energy for bees.
Protein contains amino acids, and some of these amino acids are essential. That means the organism can not make them; they have to get them in food. Dandelion pollen is low in valine, isoleucine, leucine and arginine, essential amino acids for honey bees.
Dandelion is consider a poor quality source of protein for bees.
Variety is the Spice of Life
Collecting highly nutritious pollen is important for bees but variety seems to provide them with a better ability to fight off disease. What they really need is a variety of pollen.
The type of pollen collected is influenced by the ease with which it can be collected and not by its nutritional quality. Honey bees can’t seem to tell which pollen is more nutritious. There is some evidence that bumblebees select better quality pollen.
If we make it easy for honey bees to collect poor quality pollen by creating a lawn full of dandelions – that is what they will collect. A lawn of dandelions keeps bees away from more nutritious pollen.
Even more important is to have access to pollen and nectar at all times when they are active. Native bees tend to emerge when temperatures rise above 55ºF. Bumblebees are often the first bees to emerge in spring and the last bees to be foraging in fall. Other native bees out in early spring include, Andrena spp. (mining bees), Hoplitis spp. (mason bees),Osmia spp. (mason bees), Lasioglossum spp. (sweat bees), Anthophora spp. (digger bees), Nomadaspp. (cuckoo bees), and Ceratina spp. (small carpenter bees).
Honey Bees vs Native Bees
Most of the research is based on honeybees, some on the bumblebee, and we know very little about most other native bees. They probably have similar nutritional needs, but we don’t know.
Do Bees Need the Dandelions?
Dandelions are not the first source of pollen for bees.
The pollen from dandelions is of poor quality, but better than nothing. They do provide a good source of nectar.
Keeping dandelions may keep bees from using fruit tree pollen which is a better quality of pollen. In this way dandelions may actually be harming bees.
A lawn full of dandelions is better for bees than a weed free lawn, but not nearly as good as a garden with a variety of plants and no dandelions.
If you must have a lawn, consider planting fruit trees, even ornamental ones, and skip the dandelions.