About
Lathraea clandestina, the purple toothwort, is a leafless, parasitic perennial that feeds chiefly on willows, poplars, hazel and alder roots. For most of the year it is invisible underground, but from April to June, large, glossy, violet-purple, crocus-like flowers emerge directly from the soil. Seeds are ejected explosively, allowing the plant to spread up to 8 m. A fascinating and striking botanical curiosity for planting beneath suitable host trees in a moist, shaded position.
About the genus
Lathraea are leafless, parasitic perennials that feed on the roots of trees and shrubs, producing scale-like leaves underground and emerging only to flower. The purple toothwort (L. clandestina) is the most ornamental species.
Growing conditions
SunlightFull shade, Full sun, Partial shade
Soil typeChalk, Clay, Loam, Sand
Soil pHAcid, Alkaline, Neutral
Soil moistureMoist but well-drained
AspectEast-facing, North-facing, South-facing, West-facing
ExposureExposed, Sheltered
UK hardinessH7
Plant details
HabitMatforming
HeightUp to 10 cm
Spread4-8 metres
Time to full height2-5 years
Suggested usesCottage and informal garden
Native toW Europe
Care notes
CultivationDig a wide hole next to the base of the host tree/plant (preferable Willow, Hazel, Alder or Poplar) and make a wound in the base of the host stem or trunk. Press the Lathraea next to this. Cover with soil, firm in and keep watered. It may take two seasons before there is any sign of growth, and due to the wide spread of the roots, the flowers may come up some distance from where they were planted
PruningNo pruning required
PropagationPropagate by seed or root
Pest resistanceGenerally pest-free
Disease resistanceGenerally disease-free