Hemp has been cultivated for thousands of years. We share here articles and information to help you grow quality hemp. We write here the common techniques and facts regarding the cultivation of cannabis. C. sativa and C. indica generally grow tall, with some varieties reaching 4 metres, or 13 feet. Female plants produce tetrahydrocannabinol (THC) (up to 31% by weight) as the season changes from summer to autumn. However, commercial cross-bred hybrids containing both ruderalis, indica and/or sativa genes exist.