Weed growing guide

First, you'll need a bottle of water that you can get from Emma at the Gas Station.
Second, you need seed. You will need to contact Barney Roman , he's unlocked at level 15 and is available in the day time.
There are 2 kinds of seed available: outdoor and indoor.

Outdoor

To grow outdoors, you'll need to find good spot to plant. The soil needs to be good and the plant will need direct sunlight, this can be checked by looking at the plants health.
Most important, your spot should be isolated. If a police patrol see or smell your plant, they will take it away. You'll need to water your plants every 12 hours.

There are 4 kinds of seeds:

Strains	Price	Grow time	Harvest average	Drying loss	Total yield	Dried plant/hour
AK-420	30$	48h	260g	48%	135.2g	2.82g/h
Bubai Sativa	35$	54h	350g	50%	175g	3.24g/h
Skycrapper	35$	60h	420g	50%	210g	3.5g/h
Brainfuck	30$	42h	300g	53%	141g	3.36g/h

Indoor

To grow indoors, you'll need equipment from Donald at the Furniture shop.
-Pots, one for each seed.
-UV light, they can cover 8 to 9 plants.
-Air Filter, they can filter 2 to 3 plants.

There are 4 kind of seeds:

Strains	Price	Grow time	Harvest average	Drying loss	Total yield	Dried plant/hour
Ghetto Kush	45$	14h	180g	64%	64.8g	4.63g/h
Firecracker	40$	17h	300g	60%	120g	7.06g/h
Stoner Haze	45$	18h	300g	65%	105g	5.83g/h
Bong Breaker	40$	19h	280g	55%	126g	6.63g/h

You'll need to water your plants every 4 to 6 hours.
If the light is not enough you will see that the health of the plant will not be at it maximum.
When you don't have enough air filters installed your exposition will rise and you'll get a notification about it and eventually get a DEA raid.

Calculation explained
Total yield = Harvest average * ((100-Drying loss)/100)
Dried plant/hour = Total yield / Grow time

Video

See the video of Loan4Cards :