As the daylight hours gradually lengthen, the Wildlife Garden is becoming greener by the day, and ever noisier as the spring chorus of our resident blackbirds, robins, wrens, finches and tits fills the air. The woodland floor is bursting into life with different shaped buds breaking open daily – greater stitchwort today, yellow archangel, wild garlic and wood sorrel earlier this week.
But the current star of the show is the primrose – the first woodland plant of the year, now blooming profusely throughout our different habitats. Museum Botanist, Fred Rumsey, tells us more about this beautiful plant…
“The floral treats of the Wildlife Garden right now are, for me, its primroses (Primula vulgaris). They brighten up the wooded areas and hedge-banks with their distinctive pale- yellow flowers, each of which hold secrets to their pollination and biology.
Primroses come in two distinct flower forms that we call Pin and Thrum, most easily distinguished by the position of the rather globose stigma, the structure where visiting insects leave pollen to bring about fertilisation. To ensure out-breeding, with its healthy genetic consequences, primroses have a system of incompatibility linked to these differences in floral structure that we call heterostyly.
In brief: Pin flowers have long styles and low anthers, whereas Thrum plants have short styles and high anthers. Peering down into a flower’s throat if you can see the greeny-yellow ball of the stigma it’s a Pin but, if you just see the darker ring of anthers, it’s a Thrum.
Pollen from one has to go to the stigma of the other to generate seed; their positions at particular heights in the flower helping to bring this about, as pollen will be, in theory, dusted on the appropriate bits of visiting pollinators.
The two forms are often not present in equal numbers and finding both can involve a bit of a hunt – have a look at the next primroses you come across and see what form(s) you have.
We are lucky in the Wildlife Garden to have examples of all of our native yellow primulas, not just primroses but cowslips and the much less common oxlips too.
Pollinators are clearly very active here but some of the insects are not very discriminating as in our meadow we now have a range of hybrids between the different species. They can be a real challenge to identify but all are very beautiful!”
Thank you Fred.
Elsewhere in the garden our first butterfly of the year, a brimstone (Gonepteryx rhamni), was spotted on 2 April, toadspawn has hatched in the main pond and recently laid frogspawn is swelling in the shallow water of the ford.
Visit the Wildlife Garden and spot some of the many signs of Spring! We are open daily between 10.00 and 17.40.