An industrial hemp producer says marijuana growers aren't happy about his ongoing trials across eastern Australia.

Hemp is grown for seeds, oil and fibre, and, while it belongs to the same species, is a different variety to the drug plant, marijuana.

Phil Warner, from EcoFibre Industries, says marijuana contains the psychoactive chemical THC but hemp doesn't, and that makes his industrial hemp research unpopular.

He says drug growers are concerned that the pollen from the hemp will contaminate their high THC crops, reducing their virility.

"We've been pushed out of areas because the industrial hemp affects all of the open grown marijuana and depletes it. They don't like us because the pollen spread of the industrial hemp will invade the dope grown up in the bush at least five kilometres away."

Mr Warner has been trialling many cultivars of industrial hemp in various locations across the country from far north Queensland to southern Tasmania in an attempt to identify which varieties do best, under what conditions, and where the best hemp growing areas are.

He says it's a great fibre crop that can be used to make a range of products including insulation, plastic and fabrics, and is best grown under irrigation here in Australia, on well drained soils. Once established, it's a hardy crop.

"After about eight weeks it'll be around your waist. After that, it shoots away and gets up to four metres in the next two and a half months. It matures in late February and that's when you harvest it."

After harvesting the hemp is processed and the fibre (bast) and the hemp's interior pith (hurd) is separated.

However, there aren't any hemp processing mills in Australia, so trials are underway to find the best processing method.

Mr Warner has enlisted the use of a cotton gin at Carroll in northern New South Wales to see if using a gin to process harvested hemp is viable.

"The cotton gin is not designed for hemp, but it we can produce a good saleable product then we use basically everything from the module-making equipment right through to the ginning process."

Scott Davies, manager of the cotton gin at Carroll, says he's not too worried about opening his gin up to the cannabis crop, because it has similar properties to cotton.

"We have an industrial agricultural plant that only operates between four to six months per annum. Making the facility operational for those other dormant months is quite appealing," Mr Davies said.