Lactuca virosa: wild lettuce and its milky sap
Wild lettuce is a European biennial that has since naturalised in North America. Year one stays modest: a flat rosette of large leaves with wavy, toothed edges, exactly as in the photo. The following year a straight, pale green stem rises out of it, sometimes flecked with purple, and with its side branches it can approach two metres. Small pale yellow flower heads appear near the top, each open only briefly, from July into September, and insects do the pollinating. The seeds that ripen afterwards carry a feathery pappus, so the wind can take them a long way, much as it does with dandelions.
The name tells the story. Lactuca comes from the Latin for milk: break a stem and a thick, bitter white liquid seeps out that browns in the air and dries to a resinous film. That sap is called lactucarium and contains lactucin and lactucopicrin, bitter compounds from the sesquiterpene lactone group. Of all the lettuces, Lactuca virosa yields the most of it, especially around flowering time. The epithet virosa means poisonous, which says plenty about how the plant was traditionally regarded.
Sowing
- Sow in spring or autumn, preferably straight into the spot where the plant is to stay.
- Press the seeds onto moist, free-draining soil and cover them thinly at most, since they need light to germinate.
- Keep everything cool and evenly moist. Germination runs to roughly ten or twenty days, and warm soil works against you.
- Thin the seedlings to about fifteen centimetres apart and give the plants a sunny position.
Wear gloves when handling the plant and its sap, wash your hands afterwards, and keep seeds and plants away from children and pets. These seeds are sold for cultivation and study, not for consumption.
More exotic seeds at Avalon
The same category holds Hyoscyamus niger (henbane), Leonotis nepetifolia (klip dagga), Leonurus cardiaca (motherwort) and Hypericum perforatum (St John's wort), among others. Every order leaves our warehouse discreetly packed.
