Autoflowering marijuana strains are a fairly recent development in the marijuana community.

Cannabis Ruderalis is a type of cannabis that originates in the former Soviet Union, where hemp plants acclimated to the harsh conditions and a widely varied photoperiod. A photoperiod is the number of hours in a day that light shines on the plants. Cannabis sativa (as well as c. indica and c. afghanica) requires either a gradually reducing (outdoor) or a 12 hour (indoor) photoperiod to induce flowering.

Autoflowering marijuana will flower with time, regardless of the duration of available light.

At far northern (or southern) latitudes photoperiod varies from as little as a few hours of light during the winter months to over 20 hours of light during the summer. In order for the cannabis to survive these conditions it had to flower regardless of photoperiod, quite unlike the cannabis sativa from which it originated. The result of this adaptation is a plant that will automatically begin its flowering cycle, usually just a few weeks after sprouting.

Cannabis Ruderalis itself has extremely low cannabinoid levels, making it about as potent as a hemp plant (0.1 – 3% THC). Autoflowering marijuana strains are ruderalis crosses, meaning that potent marijuana varieties have been bred with ruderalis varieties to produce them.

This increases the potency considerably, with some seed companies advertising about 20% THC in their autoflowering marijuana strains. Since autoflowering strains are not sensitive to photoperiod, they can be grown under many conditions that sativa plants cannot. For example, there is no need for two different grow rooms when growing indoors.

The main reason autoflowering marijuana strains have become available and popular is that they are well suited to illegal outdoor grows. This is because the plants stay smaller and harder to see, multiple crops can be harvested during one growing season, and because harvest times are usually not when authorities are searching for mature marijuana gardens.

I personally do not recommend either autoflowering marijuana strains or illegal outdoor growing (guerrilla grows).

I will have to sample some autoflowering cannabis, and perhaps even grow a couple of the plants in my grow room, before making a real judgement on quality. I simply don’t support the development of these plants for the obvious intended purpose of secretly growing large gardens on public lands. Such operations are a serious source of pollution, due to the carelessness of those greedy enough to take such risks.