Gunnera is one of the biggest and most spectacular, architectural, herbaceous plants, commonly thought of as 'giant rhubarb'. The plants need a lot of space because it is difficult to restrict their size. They look best standing as specimen plants in a damp bog garden, or beside a large pond where the reflections reveal the prickly undersides of the umbrella-sized leaves. The fat growth buds clustered in the crown are prone to frost damage, so pile the dead leaves and stems into a mound over the plants in autumn for winter protection - they make quite a feature of their own. Grow on in any good moist garden soil. Mulch the large crowns with the leaves in regions where winter temperatures are likely to drop below -5C (20F) A heavy mulch can help these plants survive -17C (0F).