Oral Presentation Fourth Biennial Australian Industrial Hemp Conference 2024

Industrial Hemp, like countless other summer crops,  is grown in many countries globally, in changing and varying climatic environments of latitude, daylength, temperature, altitude, humidity, sunshine hours, frost and snow etc

In much of Australia, it is also usually considered a summer only growing crop (except is grown in the northern hotter winter tropics), And has been mainly irrigated, where summer rainfall  is low and evapotranspiration rates are high, especially in all of southern Australia’s Mediterranean regions cropping belts .  

BUT from our own observations, over the last 15 years in the hemp industry, with many different clients, locations of crops and more recently consulting to AgriFutures X9 National Variety trial sites ,in all States and the NT, we have noticed the strong winter survival traits of the Cannabis plant including :-  

• Cannabis species generally demonstrate a strong ability to not only germinate, establish and grow in cooler winters, but survive and thrive, and also handle -5 C frosts as a seedling!
• This phenomenon will be shown with numerous photos we have taken over the years of crops- establishing and growing vigorously in mid- winter around Australia. It can then go on to  finish as a normal commercial harvestable biomass or grain or dual-purpose crop, if it is the appropriate variety eg Auto flowering vs photoperiodic 
• Our hypothesis is that this ability to handle cold weather and chilly climates at its early stage of growth, will open hemp up,  as not only a summer crop - BUT also as a winter- spring crop!?
• This is all depending on the latitude, variety, and location
• Industrial Hemp crops can therefore possibly be sown in winter for dryland/rainfed farming rotations,  on well drained soils or on raised beds to avoid winter waterlogging.. 
• This allows the dryland crop to establish and grow vegetatively through a cool, moist wet winter/spring and be harvested before the normal Southern Australian Mediterranean climate onset -of hot and dry summers.  

Peer review, pers comms, and references on this topic from the EU, Himalayas, Canada, Poland and Russia, also suggests a unique opportunity exists for Industrial Hemp, especially in a dryland-rainfed winter cropping situation, where moisture is limited in summer, and could be a new window of opportunity. E.g. In Russia they claim seedlings can handle -15 C, once established, but do require  maximum day temperatures of over about 12 C

Note- Hemp does NOT however tolerate heavy frosts of minus  -2 Celsius during the late vegetative and flowering/grain fill stages and severe grain losses have occurred, including in Qld . In fact the anecdote is that its cold /frost tolerance seems to reduce with age from seedlings to grain fill 

If anyone is interested to be involved in some demonstration of this initiative nationally, this winter and has a license already,  we have some new and old varieties we would like to try for either grain, dual purpose or biomass scenarios.