Turnbull said the drug testing issue would be discussed with police.
"We'd like to [have testing] but I just think that if we are going to do it we'd like to do it properly."
Health Minister Andrew Little announced last week the Drug and Substance Checking Legislation Bill was being passed under urgency to give "legal certainty" to organisations such as Know Your Stuff to operate this summer.
Know Your Stuff is a volunteer organisation — partnered with the New Zealand Drug Foundation — which has been testing substances at events for five years, including 13 events in 2018-19.
However, Turnbull said the organisation did not have the capacity to be at all the festivals around the country and New Zealand lacked professional companies to do the job.
"We've looked at the Canadian operation, which is very professional and very informative, but obviously we can't get them into New Zealand without quarantine."
Asked if drugs had been a problem for the festival in the past, Turnbull said, "only alcohol".
"Alcohol is the hardest drug to manage.
"We've never had any arrests for drugs."
The festival's all-New Zealand line-up includes Benee, Fat Freddy's Drop, Shihad, The Phoenix Foundation and Six60.