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FEATURE

Many growers use hydroponic systems,
aeroponics and even aquaponics, as well
as coco coir or soil in bags or pots. We have,
however, found all of these methods to be
expensive and prone to failure, especially
the costly, high tech systems that require
many elements to be maintained by
cumbersome and complex technology.
Haygrove Tunnels: Light deprivation as
well as supplementary lighting is vital in
order to maximise production throughout
the year. Having a single automation
system that drives all aspects of the tunnel
aids decision making by having all the
relevant info on one user interface.
SA Horticultural Supplies: Optimal growth
can be achieved by mixing the ideal
fertiliser formulation for each week of
vegetative state and flower period to
during the winter months when natural Pieter-Ernst Coetzee, Haygrove Tunnels ensure maximum root, leaf and flower
daylight hours are below the threshold by SA: This is climate-dependent. Replicating growth at the correct times. Flushing
adding photoperiod supplemental lights. what works in Europe or the USA is not the media and root system once a week
The combination of these two elements necessarily what works best in South is essential to prevent salt build-up or
allows year round production of cannabis Africa, and it is therefore not necessary calcification of the roots. Managing pH
in conventional greenhouses or tunnels. to over invest in regions where growing is important for optimal results. Plants
conditions are more suitable. need a different pH as cuttings, veg and
However, the above presupposes that flower. Good results have been achieved
legacy greenhouses and tunnels (those Tamsyn Meyer, SA Horticultural Supplies: in disposable plastic grow bags as well as
with fixed, static roofs) are in fact the The optimal structure is one that requires in woven fibre bags, solid plastic pots and
optimum environment in which to grow minimal cooling and heating costs and hemp fibre bags.
plants. This is simply not the case in South offers optimal ventilation. The optimal
Africa, as greenhouses were developed growing temperature of flowering plants Q: How much space is required to
to grow plants in cold climates. In South is 22 - 25 degrees at a humidity of 50%.
Africa, they create more problems than However, plants adapt and can grow in make the production of cannabis
they solve. While there is no disputing temperatures of up to 40 degrees as long viable?
the necessity of a greenhouse to protect as ventilation and humidity are under CannaConsulting: Viable is a relative
crops from rain, wind, hail, frost and cold, control. concept. If you define it as reaching ROI
one should bring into the equation the in a reasonable amount of time, then
amount of time that a greenhouse is Black-out screens are not necessary if even a 900 square metre tunnel can be
actually needed to fulfil this protective auto/fast bud seeds are being used. It is considered viable if the right cultivation
function. By our estimates, a greenhouse also possible to trick the feminised plants methodology is used. Having said that
is required between 5 and 12 % of the into flower, regardless of light intensity or though, the projects we put together are
time for cannabis cultivation in Southern duration. a minimum of one hectare since we have
Africa; the rest of the time it actually found that both off-takers (buyers of the
isolates plants from the perfect growing Q: Please describe the specific product) and investors only start taking
environment outside, while creating a technology required for growing you seriously at this scale.
problematic microclimate with high heat
and humidity on the inside. This problem cannabis in a greenhouse? Haygrove Tunnels: We would suggest a
is then typically solved using complex, CannaConsulting: We use a highly minimum of a half hectare of tunnels as
expensive and energy hungry climate advanced nutrient delivery system well as additional buildings for drying,
control solutions but even with these, which interacts with and activates the irrigation etc.
problems such as mold still occur; this is the plant’s higher immune pathways: soil
cannabis grower’s biggest enemy and the microbiology. This is the most cost- SA Horticultural Supplies: It depends on
conditions inside a greenhouse are often effective technology available to the what approach you take as to how many
optimum for mold spores to germinate. cultivator, yielding superior results in terms plants you place per square metre; one
Canna Consulting works exclusively in of plant health and yield. We cultivate apex plant per square metre if you are low
greenhouses with retractable roof systems soil microbiology either directly in the soil stress training and spreading out the
manufactured by Cravo in Canada. This where suitable, or in raised beds or large canopy horizontally. This has been shown
allows them to capitalise on the best of woven cloth bags inside the retractable to yield 350g bud plus per metre square.
both worlds by letting the plants grow roof greenhouse. We use a no-till system This method uses fewer plants and less
outside in direct sunlight with natural and apply copious amounts of microbe labour. Four plants per square metre if you
ventilation when conditions are optimal, teas and actively aerated compost extract; are creating a ‘sea of green’ effect. This has
and by covering them with a greenhouse these are manufactured on site very cost been shown to yield 500g bud per meter
roof when protection is required. effectively. One can of course cultivate square, and uses more plants and more
cannabis using any of the commercially labour.
available technologies on the market.