Pink hawthorn

Every year, sometime in May, somewhere in the reserve, there is pink hawthorn blossom; not uniformly pink and not always in the same hedge as was pink last year but definitely pink in places. It’s very pretty but we don’t know what causes it.

We enquired of Google, thinking that it might be something to do with the soil, the temperature, a different species or subspecies, or even a symptom of disease, all of which have been associated with colour differences in flowers. But Google doesn’t seem to know.

Many authoritative voices are ready to agree that hawthorn flowers are white and sometimes pink but if you enquire further, asking why it can be pink one year and white the next, you soon find yourself in the hands of people trying to sell you tincture of hawthorn for your congestive heart failure. Authorities also agree that the bright pink and red garden varieties of hawthorn (which are all cultivars of Crataegus laevigata) are sterile so it can’t be a cross-fertilisation thing like polyanthus turning your primroses red.

To add to the confusion, the hawthorns in the middle of the reserve, in the various hedges around Kestrel Field and Cornfield, are much more prone to pinkness. If it were just a matter of hawthorn blossom being white but sometimes pink, why is it not consistently so throughout the whole reserve?

Is there anybody among our readership, either more informed than we are or better at picking the science out of a Google salad, who might be able to help?

If you found this post interesting, here is another about hawthorn: