Congrats on what looks like a strong grow based on that pic!
There are 3 main ways to tell when it's time to harvest and it's up to you to make a judgement call and then use that experience the next grow.
- Breeder's timeframe: If you got it from a reputable seedbank, they have the general flowering time in weeks. This is ONLY a guideline, so combine this with the other two.
- Pistils: Once these turn orange/amber and start curling in and new pistils aren't forming/growing then you're probably pretty close to harvest.
- Trichomes: This is the most accurate indication. You mention having trouble seeing them even with a loupe. I personally have a hard time telling the difference between clear and cloudy, especially when there are tons of trichs! However, the amber ones stick out pretty clearly. A general rule of thumb is that once about 10% of them (1 out of 10) are amber, you've entered the harvest window. Some even prefer to wait until about 30% of them are amber for a more relaxing/sedative effect.
BUT! Don't rush! It's very exciting to get to the harvest step after you've worked for months to take care of your babies! Just like others have said, resist the urge to harvest too soon. Giving a little longer often will result in better yields and better effects. It's far more common for growers, especially new ones, to harvest too early as opposed to too late.
Take a breath, keep an eye on the trichomes the best you can, and you'll harvest at exactly the right time!
