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urban-gro’s Shelly Peterson on Cannabis Cultivation Moving to Greenhouses

October 3, 2019


The future of this industry is going to
greenhouses it makes very little sense to be in a warehouse. You can control the
environment in a greenhouse just as well as you can in a warehouse depending on
the geographic location. But the energy efficiency that comes with greenhouses
is why this industry is going to be sustainable. Staying inside is
not sustainable. Two to three years ago everybody was scared of
greenhouses because the controllability factor making sure the environments were
correct making sure the light levels were correct but at that time people didn’t
have as much access to the great equipment that is available in the
traditional horticulture market. I mean cannabis is an interesting crop it’s one
of the only ones that’s grown exclusively indoors until the last year and now
we’re seeing more and more greenhouses come on board because the energy
efficiency sometimes can be as much as 75%. So in a
traditional grow when 50% of your cost of goods sold is
attributed to your artificial lighting it’s not a sustainable business long
term. When you go from a warehouse to a greenhouse you cut the lights in half and
you run your lights depending on each area’s daylight integral which is
how we measure light in a greenhouse you can cut your lighting bill by 75%-80% as opposed to just strictly
growing indoors. And that’s not 75%-80% less light fixtures it’s probably
50% less light fixtures depending on the region and then you run
those lights only when you need them they’re not running 12 hours. Most of the
day and especially in the summer you’ll get all the lights that you need from
the Sun and then you supplement it with the light. So they might kick on in the
morning they might kick on at night. In converting from a warehouse to a
greenhouse the most important thing is working with
somebody that really understands the daily light integral for your area. DLI is not a super complicated topic think of it as like a rain gauge. So
you have water that fills up a cup all day and it’s that
accumulation of water that gives you how much it rains in a day. Light’s
the same way. So it accumulates over that photo period. So for cannabis in the
flower stages its a 12 hour photo period and then it goes black. So making sure that you have the
accumulation of light which is measured in moles. Micromoles that I’ve been talking about is
an instantaneous reading of light moles is how that accumulates over that photo period. So if cannabis needs 30 to 40 moles per day how much light are you
getting from the Sun over that photo period and how much do you need to supplement for?
So in December/January if you’re only getting 15 to 20 moles and
then the light’s cut from the glazing of the greenhouse the
shadowing that’s going on you have to make up that number somewhere. So you’re planning when you’re
buying lights for those very worst days when your lights are going to have to
run a lot to make sure that you have maximum production. Because if you don’t have maximum production in those months if you don’t have the right
target intensity during those months from your supplemental light then your
production is affected. So in the dark days of December if you’re not planning
that supplemental piece correctly it affects your yield it affects your crop it
affects your environment. Those are the months that are most important to plan for. And then the rest
of the months you’ll run the lights some to supplement and then in the summer
months you won’t be you likely won’t be running the lights at
all.

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