How big does a cannibis plant have to be before you can harvest it?

You dont really go by the size of the plant. You go by the color of the trichomes or crystals on it. Get a strong magnifying glass and I would harvest when half of the crystals are amber colored and half are a milky color. Somewhere around there.

 

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Hold the plant up to your computer screen, and when it reaches to this line:

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...it's time to harvest.

Actually, you harvest when the plant is mature, which is in the hands of Mother Nature. You determine that by examining the trichomes under magnification as others have said.

 

it is determined by many stuff such as what lighting you are using, the strain, you will know when it is ready to harvest, god shall tell thee

 

On average, 8-14 weeks from start of flowering, depending on strain. Vegging can be for as long as you want indoors.

The trichs will begin changing from clear to cloudy to amber at the end, you monitor that.

 

man another I want my bud now threads....you youngsters gonna have to learn you cant rush everything. But Toastybiz has it right.

 

gave me a chuckle

_numb_