there's about thousands of marijuana plants around us.

-This is like two, three hectares.

Like 20,000, 30,000 plants.

And then you know that you're going to find a champion there

if you look long enough.

It's a massive field, full of pot.

KRISHNA ANDAVOLU: You might not know who Arjan Roskam is,

but you've probably smoked his weed.

Since 1985, Arjan has been producing some of the most

well-known strains of marijuana out of Amsterdam.

We joined up with him and his crew in Colombia to look for

three rare marijuana strains.

So after a few hours of sleep, we're headed to Cali to check

out the biggest weed operation in Colombia.

ARJAN ROSKAM: OK, let's rock and roll.

KRISHNA ANDAVOLU: First stop, the massive grow operation of

local legend "El Gato," Arjan's key Colombian contact.

He'd be our guide throughout the trip.

ARJAN ROSKAM: So here we've got guerrilla-style growing,

guys, in the mountains of the forest.

KRISHNA ANDAVOLU: Colombia produces the most cocaine in

the world, but it's also one of the most fertile places on

earth to grow cannabis.

And while the country allows for recreational amounts of

marijuana, growing weed on an industrial scale remains

highly illegal.

ARJAN ROSKAM: If you look at the

plants, they're all moving.

You feel a little breeze going through, not too much, but

just enough to make them strong and make sure there's

no stale air around the buds.

This is the biggest thing in Columbia.

It's probably maybe the biggest in South America.

Paraguay also has very big ones.

But not like this.

And not this kind of quality.

KRISHNA ANDAVOLU: In 1992, Arjan opened his first coffee

shop in Amsterdam and has since crafted his marijuana

breeding skills into a market savvy empire known as Green

House Seed Company.

He's won 38 Cannabis Cups.

He's even dubbed himself the King of Cannabis.

-All hail the king.

ARJAN ROSKAM: We thought maybe if we create a King of

Cannabis, maybe all the rappers will come.

Maybe famous artists will come.

They will spread the word for us.

BUSTA RHYMES: Congratulate the King of the Cannabis.

Salud.

KRISHNA ANDAVOLU: These days, he's often found in Amsterdam.

And when he's not there he's strain hunting, scouring the

entire world looking for rare, untouched marijuana strains,

better known as landraces.

ARJAN ROSKAM: We are the guys who travel

all around the world.

We see where the good stuff is, and we try to bring back

the knowledge that we gain here.

We are the only guys who go really into the bush and

really to the danger areas.

KRISHNA ANDAVOLU: With authentic seeds in hand, he

brings them back to the lab in Amsterdam to develop new

varieties of marijuana.

His companies bring in millions of dollars a year.

ARJAN ROSKAM: Here you see a grow room that's done with a

minimal amount of money, but intuitive perfection.

So this is the most healthy way of growing marijuana,

preserving nature, and, in the end, smoking the product.

Because it's so perfect.

How many plants?

8,000.

How many kilos?

ARJAN ROSKAM: Every crop or every year?

ARJAN ROSKAM: 4,000 pounds.

So that's 2,000 kilos.

So that's 6,000 kilos, six tons a year.

KRISHNA ANDAVOLU: So the boys are gathering around these

plants to do a little shoot for their marketing

initiatives.

They have fertilizer, apparently, that they try to

sell to people.

But this is sort of businessman

Arjan at work again.

ARJAN ROSKAM: The bags are in good height.

Our faces are good visible.

-Fuck yeah.

Fuck yeah, man.

KRISHNA ANDAVOLU: As marijuana becomes legal in more and more

countries around the world, Arjan Roskam has set himself

up to be the first billionaire of bud.

FRANCO LOJA: They are raising them already.

It's three weeks away from being harvested.

Incredible.

KRISHNA ANDAVOLU: Arjan's business partner and head

breeder is Franco Loja, a paratrooper in the Italian

military turned grower.

FRANCO LOJA: I used to be perceived as a criminal when I

was in Italy.

Now I'm a guy that has 50,000 fans on Facebook, and people

ask for autographs and want to take pictures with me.

The beauty of cannabis, the power of

cannabis is its variety.

It's the fact that there are so many flavors, so many

effects, medicinal and recreational.

It's a plant, but it's not one plant.

It's thousands of plants.

ARJAN ROSKAM: Now as we look, we are in a great plantation,

but it's still very illegal.

You know what the people are doing here.

And they're all jeopardizing their life and prison and

everything.

-[SPEAKING FOREIGN LANGUAGE]

ARJAN ROSKAM: The people who are running this operation

lost their father, their brothers.

So this gives you just an idea of how rough the past was.

And now they're marijuana growers.

That's the greatest thing on earth.

They go from the guerrilla to growing marijuana.

What else you want to have on this planet?

KRISHNA ANDAVOLU: That's not dirt he's scooping up.

You're looking at dried resin, soon to be hash.

-[SPEAKING FOREIGN LANGUAGE]

KRISHNA ANDAVOLU: On this particular expedition, the

guys have come to Colombia to hunt for

three legendary landraces.

Limon verde, punta roja, and Colombian gold.

Since it was too dangerous to stay at the grow-op we would

start hunting for the limon verde the next morning.

Then we got stuck.

ARJAN ROSKAM: Our truck is stuck.

We're going to have to push it out.

KRISHNA ANDAVOLU: We had heard horror stories about what

happens in the southern jungles of Colombia at night,

and Gato told us that FARC guerrillas abducted a French

journalist last year and that this June, an American was

stabbed to death by bandits on the road.

We knew we had to get the hell out of there.

So we can't fucking move the truck.

We moved it about five meters or so, but

then it's stuck again.

We've been putting a bunch of vegetation and shit under the

wheels, and it's moved, but it's not going to work.

This is fucking tough.

It's muddy out here.

And I don't think this truck is going to move tonight.

-Push, push!