This Sunday the volunteers will be planting some genuine vampire plants!
The plant is called Yellow Rattle (Rhinanthus minor), and it grows partially through the standard means, and partially through parasitizing other plants by growing into their roots.
It needs to be sown in autumn time, the flat seed then lies on top of the soil until germination in February or March. It also needs to be exposed to cold winter temperatures to germinate.
Germination and first growth is the tricky stage – if there is too much grass, or it is too long the germinating plant will be unable to get enough energy from the sun. If there is not enough grass the developing plant will have nothing to parasitize and will struggle to thrive.
We will be planting several plots in the solely grass areas of the wildlife meadow, in the hopes that we manage to get some established. We are going to attempt to strike the right balance of grass versus no grass by vigorously raking over the plots to expose some bare soil before sowing.
If we get it right, and if the general growing conditions are suitable then after germination the plant should throw up a couple of shoots with spiky leaves that look a wee bit like stinging nettles. These will flower late May or early June with pretty yellow flowers that are attractive to bumblebees and other insects. By July the seed pods will have formed and dried, and if you listen carefully you will be able to hear them rattling in the breeze.
As well as benefiting wildlife, if we can get these plants established it will also benefit the plant-life in the meadow. As you will remember, most of the meadow area was not seeded with wildflowers – it is simply “park grass” left to grow long. The issue with this grass is that it is a very robust and vigorously growing plant, that tends to crowd out other plants. These characteristics make it excellent for mown grass areas in parks – less good for wildflower meadows.
Due to the parasitic nature of this plant, if we can get it established, we hope that it will be able to significantly weaken the existing grass in order to give all of the other wonderful flowers in the meadow a chance to spread and colonise the rest of the area.
You may wonder what will stop the Yellow Rattle spreading and parasitizing the other flowers – the answer is nothing. Generally the Yellow Rattle reaches a happy equilibrium with the other plants in a meadow, If necessary, however, it can be easily controlled by simply cutting before it gets a chance to seed as it is an annual plant. We will be keeping our fingers crossed that we see some shoots in the spring!