Do it frequently enough that you remove the flower heads before they become seed pods. Other growers prefer to get rid of the middle man and plant their seed straight into their first flowerpot it s essentially how it would be done in nature, so why not follow the natural order. You can learn more about the cookies that we use, and opt to save your preferences, by clicking Cookie settings.  Source: <a href=https://ipllive2018.com/7-cfr-201-16-noxious-weed-seeds-digital-code-of-federal-laws-e-cfr-lii-legal-information-institute_922851.html>https://ipllive2018.com/7-cfr-201-16-noxious-weed-seeds-digital-code-of-federal-laws-e-cfr-lii-legal-information-institute_922851.html</a>