Second first grow :)

There are a variety of ways to know when your plants ready to harvest . Firstly let's talk about the method we would use with a micro lense or a portable microscope. These tools will give you the proper magnification to see the heads on your trichomes when most of they heads are milky accompanied by some amber ones then you know you can harvest and get good quality medicine . If they are still clear that means the thc is still developing and isnt quite ready at that moment in time . Deciding when to harvest using this method will be widely debated so it will come down to a preference thing . Provided the heads aren't clear your going to do well . Now another way you can tell your plants nearing harvest is that leaves on your plant will start to change colour , if you still have mostly green leaves then your plants still healthy and growing . You can look at the flowers if most of hairs are orange and the flowers aren't really producing and new hairs then that's another good sign . This will usually be accompanied by your flowers slowing down in growth . Lastly check the breeder recommended flowering time and add 2 weeks to it this will ensure you plants ready for harvest and you will notice the other signs I've discussed along the way . All the signs that your plant will give you dont require any sort of tool . Only if you wanna look at your trichomes up close and personal do you need the proper tools for it, they can be found in a variety of places they're pretty common . Amazon , walmart , local grow shop , home depot , Ebay that's just to give a few . I hope this information helps you on your quest to the finish line!! Happy Growing !