If you are growing a strain that you have grown many times, you probably already have your harvest schedule for that strain fine-tuned. But what if you are growing a new strain? How do you know when to harvest?
There is a fairly narrow window, in terms of time, when you can harvest your buds if you want to get the highest quality. This window can be a few days to a week long. If you harvest too early, the buds will not have reached their peak THC levels. If harvesting too late, they will have begun to degrade and be lower quality. There are a couple of rules of thumb for determining when to Harvest.
The first rule is to watch the white hairs on the flowering buds. When 50% to 75% of the hairs have turned from white to a color (orange, red, purple, lavender, brownish, etc.), then it’s time to harvest.
The second, more accurate rule of thumb involves inspecting the trichomes on your plants. You can inspect the trichomes with a magnifying glass, jeweler’s loop or digital camera. If you are using a digital camera, take close-up pictures and inspect them on your computer screen, enlarged as much as possible for a detailed look at the trichomes. When about 75% the trichomes have swelled up and turned milky (no longer clear) or 50% have turned amber, it’s time to harvest.
Timing Indica Dominant Strains
If you are growing an Indica Dominant Strain, you’ll likely have flowering periods that range from 45 to 70 days. When you get to the last five days of your expected flowering period, it’s time to start closely inspecting the trichomes. So, if your strain has a flowering period of 45 to 50 days, when you come to the 45th day of your flowering light cycle, you should start inspecting the trichomes.
Timing Sativa Dominant Strains
Sativa Dominant strains have longer flowering periods than Indica strains. Some Sativas are in the 60 to 75 day range for flowering and some are even longer — as long as 80 to 120 days flowering for some strains.
If your Sativa dominant strain has a flowering period of 75 to 90 days, when you come to the 85th day of your flowering light cycle, you should start inspecting the trichomes.
Timing Unknown Strains
If you don’t know the genetics of your strain, and you want to use the more precise timing method, you may have to examine the buds daily to find the peak time. Start examining your magnified trichomes when 20% to 25% of the hairs on your buds have started to change color.
Since you don’t know the flowering period for your strain, you will be starting toward the early days in which flowering may reach its optimum. You will need to examine them every day or at least every other day until they are ready for harvest.