Shepherd’s purse is a fast growing, prolific annual or biennial weed that can either quickly grow, flower and set seeds in a matter of weeks or, towards the end of the year, overwinter and then flower and seed the following year.
Each plant produces thousands of seeds and huge numbers of seedlings throughout the year, with up to three generations per year. The seedlings quickly colonise large areas of the garden, making it difficult to control if allowed to become established.
These seeds can remain dormant in the ground for several years. And as “One year’s seeding means seven years weeding”, allowing plants to flower and produce seeds, means several years of trying to control and remove it.
Shepherd’s purse is also a host plant for the disease white blister, which affects brassicas, Aubrieta, honesty, wallflowers and several members of the daisy family.