And once the pistils have all darkened you can start scoping the trichomes with a loop. 30-60x if you have one. They're also very helpful for checking for bugs. The trichomes will go from clear (not ready) to cloudy (max thc and an 'up' high) to amber (more of a 'couchlock' effect). Then it's grower's choice on when to harvest depending on the effect you're after. I personally like more amber, but plenty of others like it more uplifting.When she is finished flowering and building for you her white pistils turn red and crinkle in.
She will stop eating also.
As long as you have white pistils and she is still eating regularly she is still flowering.
A couple weeks will help.
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Another thing I think you should consider for your next grow is a SIP (sub irrigated planter). This is a grow pot with a built in water reservoir and air pocket for the roots. Makes correct watering almost foolproof and you get much bigger and healthier plants because if it.
There are a few threads going that are using them and we are having discussions on how they work, where to get them or how to build your own if you are so inclined.
Here's a couple of them if you want to follow along, but they are great for new growers:
Buds Buddy's grow
LKABudman's grow
Another alternative is to use @Bill284 's soil layering method with extra perlite found in his thread Here
Either approach will help you max out your plants' potentials with little extra input or effort.
And another thing that can help maximize yields for little extra effort is training. Personally I like Quadlining but there are several different approaches to consider.