Industrial hemp legislation has passed the South Australian Parliament, with farmers expected to be free to plant crops within weeks.

"This is a new opportunity for farmers but it will also mean that those who sell and manufacture hemp products now in South Australia won't have to source their materials from interstate or overseas" said Greens Upper House member Tammy Franks, who sponsored the bill.

The current hemp industry in South Australia includes manufacturing of clothes, cosmetics and building materials.

Industrial hemp is defined as containing less than 1 per cent of the psychoactive drug THC.

"You could try and smoke it but there's no way you'd get stoned," Ms Franks said.

"You might get a headache but there's no way that this can be used as a recreational drug."

The Greens secured backing from both Labor and the Liberals to ensure passage of the bill.

Most other Australian jurisdictions already have such laws.

SA Manufacturing and Innovation Minister Kyam Maher said it remained to be seen how many primary producers would be interested in growing hemp crops.

"We don't know how big it might be, but we want to make sure there's every opportunity to people who may have an interest in this," he said.

"We will set up the regulatory framework and it will be up to farmers and manufacturers to decide if it's economic and it's something that they want to do."

Ms Franks remains keen for South Australians to have easier access to medical cannabis.

It technically became legal after Federal Parliament passed legislation last year, but each state must individually regulate how patients can access it.

Mr Maher said it could now be prescribed to some South Australian patients and efforts were underway to reduce red tape.

"In the coming weeks we'll have more to say about that," he promised.