You harvest when the trichomes are a certain colour.

The THC you are looking for in in the trichomes. Looking at the colour of the pistils is a mistake many new growers make.

You need to get yourself a 60x jewellers microscope. I got mine for $3 on eBay. I have since bought a 400x USB microscope.

Trichomes generally have 3 different colourations you need to know about. Clear, milky and amber.

When the trichomes are all clear it is too early to harvest. When they turn mostly milky the THC level is at its peak. when most are amber the THC naturally breaks down into CBD.

When the trichomes are mostly milky harvesting will give your weed a more heady, energetic effect. If you leave the plants go mostly amber you will get a heavy, body high.. couchlock.

A lot of growers look for the middle ground between milky and amber.

Here are some random pictures from my microscope. The weed here was old and bagged so most of the trichomes are broken. But you can find lots of info on trichomes and harvesting here.

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