How to Propagate oak 'Koster'?
Propagate by seed, sown as soon as ripe, in a cold frame

oak 'Koster' · Quercus robur 'Koster'
Also known as: oak 'Fastigiata Koster'
Grows well in most deep, fertile soils and is lime tolerant
Propagate by seed, sown as soon as ripe, in a cold frame