Which Wildflowers Provide The Most Nectar And Pollen For Bees?

In 2016, Hicks et al¹ published a paper, in which the average nectar and pollen reward of a number of wildflowers was compiled and presented in tables - along with other data recording and measuring a variety of factors.

Below, I have taken parts of the data and present it here to provide an overview of the average (mean) nectar and pollen reward recorded for each flower, as well as the average floral longevity (in days).

Why might this data be useful?
If you are considering adding wildflowers to your flower border, you might be looking for information on which to include, based on a desire to provide the maximum amount of food for bees in the form of nectar and pollen.  Both nectar and pollen are important for feeding individual bees and for rearing larvae.

However, it's worth noting there are limitations to the data - for example, a number of beautiful and very beneficial wildflowers are not included, and I elaborate on a number of considerations below.

Selecting Wildflowers For Nectar And Pollen

It's no secret that bees need nectar for energy which they get from the carbohydrate sugars, and pollen for lipids, protein and for maintaining good health.

Some flowers offer an abundance of both for bees to feed on, whilst others provide only one, but in abundance.  Of course, some flowers offer little of value to bees. 

Additionally, there are pollinator species which have a preference for only one or two plants (pollinator constancy), and seasonality factors are also relevant, as well as local environment.

Which wildflowers should I include in my garden?

5 recommended wildflowers

If you have limited space, then based on the lists below, and my own personal experience, my top 5 recommended wildflowers from those listed in the tables are:

Below are the tables outlining the data in µg (micrograms).

I provide my reasons for recommending certain wildflowers and not others, below the tables.

Wildflower pollen reward

Common name	Scientific name	Mean volume of pollen per flower per day (µl/day)	Floral unit longevity (days)
Musk Mallow	Malva moschata	2.274	2.232
Common Knapweed	Centaurea nigra	2.058	3.112
Dandelions	Taraxacum agg.	1.255	2.250
Ox-eye Daisy	Leucanthemum vulgare	1.077	14.783
Rosebay Willowherb	Chamerion angustifolium	0.689	4.200
Corn-marigold	Glebionis segetum	0.609	8.333
Cat's-ear	Hypochaeris radicata	0.365	3.526
Scentless Mayweed	Tripleurospermum inodorum	0.348	8.500
Autumn Hawkbit	Scorzoneroides autumnalis	0.274	6.684
Meadow Buttercup	Ranunculus acris	0.262	5.345
Yarrow	Achillea millefolium	0.247	4.565
Rough Hawkbit	Leontodon hispidus	0.157	6.684
Smooth Hawksbeard	Crepis capillaris	0.145	5.056
Daisy	Bellis perennis	0.145	4.500
Pineappleweed	Matricaria discoidea	0.134	3.216
Prickly Sow-thistle	Sonchus asper	0.120	7.824
Red Campion	Silene dioica/latifolia	0.115	3.128
Smooth Sow-thistle	Sonchus oleraceus	0.112	11.857
Nipplewort	Lapsana communis	0.107	3.087
Creeping Thistle	Cirsium arvense	0.104	5.769
Common Ragwort	Senecio jacobaea	0.099	9.530
Creeping Buttercup	Ranunculus repens	0.088	4.820
Viper’s Bugloss	Echium vulgare	0.064	2.360
Wild Mignonette	Reseda lutea	0.043	4.519
Bird`s-foot-trefoil	Lotus corniculatus	0.036	4.050
Common Mouse-ear	Cerastium fontanum	0.035	1.000
Dove's-foot Crane's-bill	Geranium molle	0.033	1.000
Common Field-speedwell	Veronica persica	0.031	1.000
Selfheal	Prunella vulgaris	0.029	1.090
Tufted Vetch	Vicia cracca	0.028	1.350
Common Groundsel	Senecio vulgaris	0.028	6.294
Broad-leaved Willowherb	Epilobium montanum	0.026	2.000
Red Dead-nettle	Lamium purpureum	0.019	1.052
Common Hemp-nettle	Galeopsis tetrahit	0.017	1.912
Charlock	Sinapis arvensis	0.015	2.575
White Clover	Trifolium repens	0.014	2.058
Wild Red Clover	Trifolium pratense	0.012	1.675
LesserStitchowort	Stellaria graminea	0.007	3.065
Hairy Tare	Vicia hirsuta	0.006	1.000
Ribwort Plantain	Plantago lanceolata	0.005	2.362
Common Fumitory	Fumaria officinalis	0.005	2.031
American Willowherb	Epilobium ciliatum	0.003	3.063
Common Knotgrass	Polygonum aviculare	0.003	2.000
Wild Marjoram	Origanum vulgare	0.003	3.594
Hedge Mustard	Sisymbrium officinale	0.002	3.000
Redshank	Persicaria maculosa	0.002	1.141
Wild Carrot	Daucus carota	0.002	8.450
Lady’s Bedstraw	Galium verum	0.001	6.974
Hedge Bedstraw	Galium album	0.001	7.440
Common Chickweed	Stellaria media	0.001	2.235
Field Forget-me-not	Myosotis arvensis	0.000	3.635

Wildflower nectar reward

Common name	Scientific name	Mean volume of nectar sugar per flower per day (µg/day)	Floral unit longevity (days)
Common Ragwort	Senecio jacobaea	2921.434	9.530
Creeping Thistle	Cirsium arvense	2608.941	5.769
Spear Thistle	Cirsium vulgare	2322.728	na
Dandelions	Taraxacum agg.	2137.198	2.250
Cat's-ear	Hypochaeris radicata	1843.239	3.526
Rough Hawkbit	Leontodon hispidus	1826.716	6.684
Common Knapweed	Centaurea nigra	1473.808	3.112
Scentless Mayweed	Tripleurospermum inodorum	1415.790	8.500
Corn-marigold	Glebionis segetum	931.210	8.333
Viper’s Bugloss	Echium vulgare	688.269	2.360
Prickly Sow-thistle	Sonchus asper	593.827	7.824
Smooth Sow-thistle	Sonchus oleraceus	568.844	11.857
Musk Mallow	Malva moschata	540.649	2.232
Autumn Hawkbit	Scorzoneroides autumnalis	536.175	6.684
Ox-eye Daisy	Leucanthemum vulgare	515.213	14.783
Wild Mignonette	Reseda lutea	360.574	4.519
Rosebay Willowherb	Chamerion angustifolium	282.900	4.200
Creeping Buttercup	Ranunculus repens	258.854	4.820
Selfheal	Prunella vulgaris	246.929	1.090
Red Campion	Silene dioica/latifolia	144.994	3.128
American Willowherb	Epilobium ciliatum	144.713	3.063
Wild Marjoram	Origanum vulgare	144.068	3.594
Meadow Buttercup	Ranunculus acris	122.500	5.345
Tufted Vetch	Vicia cracca	110.219	1.350
Red Dead-nettle	Lamium purpureum	107.732	1.052
Nipplewort	Lapsana communis	99.347	3.087
Bird`s-foot-trefoil	Lotus corniculatus	59.172	4.050
Daisy	Bellis perennis	51.067	4.500
Wild Red Clover	Trifolium pratense	48.366	1.675
Broad-leaved Willowherb	Epilobium montanum	36.566	2.000
LesserStitchowort	Stellaria graminea	32.159	3.065
Yarrow	Achillea millefolium	31.105	4.565
Redshank	Persicaria maculosa	29.586	1.141
Wild Carrot	Daucus carota	27.177	8.450
Hairy Tare	Vicia hirsuta	26.763	1.000
Common Fumitory	Fumaria officinalis	21.898	2.031
Field Forget-me-not	Myosotis arvensis	21.834	3.635
Germander Speedwell	Veronica chamaedrys	21.383	2.107
Dove's-foot Crane's-bill	Geranium molle	19.273	1.000
White Clover	Trifolium repens	12.135	2.058
Common Chickweed	Stellaria media	11.918	2.235
Common Mouse-ear	Cerastium fontanum	11.589	1.000
Shepherd's purse	Capsella bursa−pastoris	9.052	1.465
Hedge Bedstraw	Galium album	7.056	7.440
Charlock	Sinapis arvensis	5.687	2.575
Common Field-speedwell	Veronica persica	4.686	1.000
Hedge Mustard	Sisymbrium officinale	3.675	3.000
Lady’s Bedstraw	Galium verum	3.173	6.974
Smooth Hawksbeard	Crepis capillaris	0.000	5.056
Pineappleweed	Matricaria discoidea	0.000	3.216
Ribwort Plantain	Plantago lanceolata	0.000	2.362
Common Groundsel	Senecio vulgaris	0.000	6.294

Rationale for recommendations
You may note that there are some wildflowers that score highly, which I exclude from my 'top 5' list above, such as dandelion. 

My reasoning is as follows:

• The other wildflower species which score highly, are generally found in abundance in most regions, and arguably, there is no great need to cultivate them in a garden setting.
  
  
• I have selected for value to a range of bee species, and for beauty.  I think most people looking to incorporate just a few wildflowers into their garden border and maximize available space, would prefer not to use flowers such as Cat's Ear (not that there's anything wrong with it), whereas the mallows offer tremendous value and are extremely pretty. 
  
  
• I recommend other wildflowers for particular scenarios elsewhere on my website.  For example, I have long advocated allowing clover to flourish in the lawn.

Limitations of the data as presented above

• It's important to note that the study from which I extracted the above data, provided discussion and outlined a number of variables not covered here.   In other words, this article, which is already rather long, is only giving part of the story from the study.
  
  
• The study did not and could not reasonably be expected to cover every single wildflower known, and there are a number of flowers for which data is missing.  
  
  For example, Field Scabious (Knautia arvensis) is known to be very beneficial to pollinators.  One study found that it provided a mean (average) nectar reward of between 2.73 and 4.33µg (micrograms) per plant species across 4 sample groups, and a range of beneficial amino acids.  It received visits from bumble bees, honey bees, solitary bees and hoverflies².
  
  
• As stated previously, when planning your bee-friendly garden, it's worth taking into account flowering season, and if possible, aim to plug gaps when there might otherwise be a shortage of nectar and pollen.  This element is not covered in my tables above.  In addition, select a variety of flower shapes.
  
  
• Remember some pollinator species have a preference for particular types of flowers.  for example, you can't go wrong with Lamb's ear to attract wool carder bees, or Pulmonaria to attract Hairy footed flower bees.
  
  

Nevertheless, the 5 species of wildflower mentioned above are all of great benefit to bees and pollinators, and certainly worthy of inclusion in the garden border.

References

1. Hicks DM, Ouvrard P, Baldock KC, et al. Food for Pollinators: Quantifying the Nectar and Pollen Resources of Urban Flower Meadows. PLoS One. 2016;11(6):e0158117. Published 2016 Jun 24. doi:10.1371/journal.pone.0158117

2. Venjakob, Christine & Leonhardt, Sara & Klein, Alexandra. (2020). Inter-Individual Nectar Chemistry Changes of Field Scabious, Knautia arvensis. Insects. 11. 75. 10.3390/insects11020075.