Fen Violet Project

In May of this year there were several pleasing reports in the national media that fen violet, Viola stagnina, had been recorded in the wild at Wicken Fen for the first time since 2003. This is one of only three sites known in the country, another being Otmoor near Oxford. The  Oxford Flora Group has been actively monitoring the status of this plant for several decades and hopes to establish populations in other sites in Oxfordshire. At the Botanic Garden we have been raising plants to provide material for these projects. This summer Tom Carruthers, an undergraduate in Biological Sciences from the University of Oxford, has been conducting some research on Viola stagnina:

Wild fen violet flowering on Wicken Fen, May 2014

Fen violets growing at the Botanic Garden

The last few months have seen literally hundreds of fen violets take over a corner of the Botanic Garden. These violets are part of a project I am carrying out to determine the effects of potassium on this endangered species. The project started in March, when, over one weekend, I potted 386 of the plants into pure perlite, creating a somewhat dazzling sea of white. Thankfully over the next few weeks the plants started to grow. This was a great relief as the plants had never been grown in perlite before. I had also seen a few slightly surprised looks on the faces of the staff at the gardens when I mentioned I would be growing them like this! 

By the beginning of May, the plants had grown sufficiently to cover the bright white perlite they were growing in and by the middle of May they were producing lots of their characteristic pale violet flowers. 

By this time the data collection operation was also in full swing. The purpose of the investigation is to determine the effect of high potassium levels on the plant, given there are some reports that high potassium has had a positive effect on wild populations. Because the Botanic Garden has a number of different genetic ‘lines’, I will also hopefully be able to determine the extent to which genetic variation affects their response to potassium. I am therefore busy taking measurements of the plants to see if there are differences in the timing of flower production and the ratio of sexual to asexual flowers produced. I will also take other measurements, such as the extent of seed production later in the year.

Hopefully the results from this experiment will provide valuable information to help maintain wild populations of this species in Great Britain.  

                                                                                     Tom Carruthers