A raid at a Hamilton Kent Road property on Thursday uncovered 317 cannabis plants ranging in size from seedlings through to mature plants ready for harvest.

Detective Senior Constable Nick Roberts, of the Hamilton police crime investigation unit, said the plants had a potential street value in excess of $600,000.

Three middle aged Vietnamese nationals, two men and a woman, were arrested, interviewed and charged with cultivating a commercial quantity of cannabis.

They appeared briefly in Warrnambool Magistrates Court on Friday for a filing hearing and were remanded in custody until September 18.

South-west police have dealt a number of blows to the local marijuana supply in the past six months, uncovering six grow houses and seizing 1442 cannabis plants with a value of about $3 million.

Detective Senior Constable Roberts said the Kent Street address was linked to a home in George Street previously raided by police in mid-March where officers found a cannabis drying operation.

The George Street operation was then linked to a grow house discovery in a Horsham residential street.

In October last year the south-west's first grow house was discovered by police in Warrnambool's Sundale Road, where 262 plants were located.

In March the drying operation was found in George Street, followed soon after by the grow house in Horsham, which was linked by a finger print.

Then two crop houses were located in Portland in 10 days, one at the end of April and the other at the start of May.

It's understood those involved in crime syndicates are buying properties and setting them up as grow houses in regional areas as the price of properties skyrockets in Melbourne.

Investigations are continuing into the possibility of the grow house properties being seized by police.

Detective Senior Constable Roberts said the houses were being fitted with sophisticated hydroponic set-ups.

"Each home is being significantly modified, such as electrical bypasses being installed, as well as transformers, lights, water and nutrient systems. It would have to cost $50,000 to install each of these set-ips," he said.

"We are requesting that anyone who sees unusual activity at a property in their street, such as lights coming on and going off at the same time each day, contact police.

"It is only through information from the public that we can identify these properties, execute warrants and dismantle the operations," he said.

Anyone with information in relation to illegal drug activities is requested to contact their local police station or Crime Stoppers on 1800 333 000.

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