Petty Spurge, Cancer Weed, Radium Weed
Euphorbia peplus is an annual that grows up to 30 centimetres high and shows its inflorescences from May to October. In mild regions it can produce two generations per year, so that fruiting specimens can still be seen in December.
As with many other spurges, all parts of the plant are poisonous. Petty spurge contains ingenol mebutate, which is used in the USA to treat actinic keratosis but is no longer licensed in the European Union.
The natural range of the Petty Spurge includes Europe, North Africa and Asia, where its range extends to India and Pakistan. As an introduced species, it is also found in other regions, including Australia, New Zealand and North America (source).
Euphorbia peplus is not only found in gardens, but also in parks, cemeteries, fields, rubble tips, roadsides, shrub banks or dams. It lives in sunny to shady areas.
It thrives best in evenly moist, humic to loamy soil. In such locations it tends to form extensive stands. It can also grow in sandy soil, but remains much smaller or does not establish itself permanently.
Petty spurge is well adapted to survival in urban areas. It can grow between paving stones, kerbstones, in front of or on walls.