One of my focus areas at Hidcote is propagation and this week I was fortunate to have the opportunity to visit the Millennium Seed Bank at Wakehurst in West Sussex to take part in a National Trust Seed Collecting Training Session. Launched in 2000, the Millennium Seed Bank Partnership is the largest ex situ plant conservation programme in the world, conserving seeds from plants which are either facing extinction or which are of particular value to communities around the world. Recently the Millennium Seed Bank has begun working with the National Trust to conserve some of the many rare or unusual plants in National Trust Gardens.
As part of the training day we learnt how to check for the ripeness of seed in fruits and nuts by cutting these in half with secateurs or a sharp knife, and for smaller seeds by shaking the seed heads into a tray or tub.
We also learnt how to produce herbarium specimens by sandwiching plant material between sheets of newspaper and cardboard in a plant press. Herbarium specimens are sent to the Millennium Seed Bank alongside collected seeds as a plant identification reference point. Good herbarium specimens should contain a plant cutting which shows the stem, leaves (both sides) and any flowers or fruit if present. Flowers can also be cut in half to show the reproductive flowers and added to the specimen.
Inside the seed bank we learnt about how the seeds are processed and stored once they arrive and the data that is required from National Trust gardens in order to record them accurately. Ripe seeds are air-dried to 15% relative humidity in specialised drying rooms, before they are packaged into airtight containers and transferred to a cold room for storage at -20°C.
After the training I took the opportunity to have a look at the beautiful gardens of Wakehurst Place. Wakehurst is the country estate of the Royal Botanic Gardens, Kew, and is leased to them by the National Trust. Famed for its beautiful botanical gardens and extensive tree collections, the garden certainly didn’t disappoint me – just take a look at these pictures…