Lower Risk

Hydrangea quercifolia (Oak Leaf Hydrangea)

This deciduous shrub is native to the south-eastern United States. Despite being in the ornamental trade in Australia since 1964, the species has not naturalised. There is also no evidence Oak Leaf Hydrangea has naturalised elsewhere outside its native range. Reproduction is via both seed and vegetative means (stolons and root suckering). The fruit is a dry capsule that persists on the plant. Hydrangeas contain cyanogenic glycosides, which in large doses may cause heart or respiratory failure. Oak Leaf Hydrangea is also toxic to dogs, cats and horses. The shrub produces beautiful creamy white flowers.