Photo: Blackstem Plants
Rheum palmatum var. tanguticum
A gargantuan monster of the rhubarb family and one of our favourite plants. Each leaf can attain 45cm or more and they act as perfect umbrellas when we're caught in a light shower. However, these leaves and indeed the whole plant, are very poisonous so keep this beast away from edible rhubarb.
It needs deep, fertile, moist soil and grows splendidly by the side of a pond or in a bog garden. It will tolerate shade so can grow well in moist woodland. Once established there is no mistaking this for any other plant.
The imposing two metre flowering stem bears erect panicles of crimson flowers that turn into a column of brown papery seeds but it isn't invasive.
If it's large foliage you're after then this is the plant of choice.
Full sun, partial shade