Your plants have been growing for weeks now. You’ve done everything as learned online and those buds on your plants have become nicely big.
You can even see the trichomes on them already and they’re looking really nice. They’ve just started to turn milky in colour. The tops of those plants are starting to look frosty.
Only two weeks anymore and you can harvest your grow. Now is an important stage in the grow process and one which will help you get a smooth flavor for your weed. Nobody likes tasting harsh, throat cutting weed. As if rodents are playing in your throat... no thanks.
It’s time to flush your grow now to get a pleasant smoke.
What is Flushing?
While growing your plants have collected nutrients. These may have come from the soil you used and the supplements you’ve used during the growth. Your plant, and the soil, is now full with these nutrients and minerals.
When flushing your plants, you remove all nutrients and minerals from the soil and force the plant to use up the remaining nutrients it has in it. If done rightly your buds will be free of any nutrients and minerals when you harvest them and you will end up with a nice smooth smoke.
It’s important to find the right moment to flush your plants. If you start flushing too late you may not have flushed all nutrients out and the taste of your weed is still affected. If you flush too early, your plants’ final growth may be affected and your yield will be lower.
Flushing takes up to two weeks normally. The best time to start flushing is at the beginning of the harvest window.
Almost half of the white hairs (pistils) have turned dark and half of the trichomes have become half cloudy in appearance (milky in colour). This is usually a great time to start flushing.
If you struggle to see if the trichomes are still clear (glass like) or are starting to turn cloudy already, use a cheap jeweler’s loupe or magnifier. The most hardcore growers will even have a microscope to check the trichomes and decide when is the right time to start flushing their cannabis plants.
For most plants this will be 6-8 weeks in the vegetation stage. Make sure you know what is the usual time to harvest for your strain.
Don’t worry about starting on the exact day, cannabis plants have a harvest period of several weeks and will continue to develop during those weeks.
If you’re going for the highest possible THC in your buds, then you have to start flushing early in the harvest window. If you want a smoother effect, start a flushing little later.
How to Flush
Flushing your cannabis plants is as easy as watering them. Just leave the nutrients and supplements out. Water your plants with clear water.
Make sure to still keep an eye on the pH level of your water as you don’t want to shock your plants with an unhealthy pH.
When flushing your plants, water the plant with as much water as the pot can hold. Wait some minutes so the water can absorb as many nutrients as possible. Flood the soil again.
Flush your plants at the same time you would normally water them.
Things to Watch Out For
During the flushing stage it is common that the leaves of your plants start turning yellow. This is because gradually the plant is living of always less nutrients. When almost all fan leaves turned yellow your plant won’t mature any further and you may loose potency in the buds very quickly.
As you near the ideal harvesting time, always more fan leaves will turn yellow. Keep an eye on the small bud leaves, the sugar leaves, though as they should still be green when harvesting.
As soon as the small leaves on the bud have started to turn yellow you should harvest your plant before it starts spreading to the bud.
Generally plants will not mature anymore once the leaves are not green anymore. Make sure to know the genetics about your plant because obviously we now have strains which turn red or dark. But, usually, when the leaves have changed colour and are not green anymore the time to harvest has come.
Note for coco-growers: growers who use a coco-soil mix have a slightly shorter flush period of around a week.
Opinions about the recommended flushing time vary. The ideal duration depends on the soil composition, the grow method, and also how many supplements you’ve given your plants. Fo most regular grows it is safe to say that flushing will take 10-14 days. Some specialists will recommended merely a week of flushing.
When’s the Ideal Time to Harvest?
Depending on what you prefer from your weed, you will harvest sooner or later.
If you want maximum THC, then you will harvest when most trichomes have turned milky in color. Around 2/3 of the pistils will have turned darker as well. Use your jeweler’s loupe to check the trichomes to be sure.
Almost all pistils have turned dark
If you prefer the so-called “couchlock” effect, then you will harvest a little later. You wait until the trichomes have turned darker, amber in colour. More than 3/4 of the pistils have become darker as well now. Now some of the THC will have become CBN (cannabinol), which is responsible for the calming, sedating effect and also helps with insomnia.
The later you harvest, the more sedating your buds will be.
Make sure to take that preference in account when deciding when it’s time to start flushing your cannabis plants.
Inform Yourself Before Starting
If you purchased your seeds from a reputable store or breeder/grower they can advice you on what is the ideal vegetation time and when does the harvest time for that strain usually start.
Practice makes master and an informed grower is a wiser grower.
After harvesting comes the time to cure your cannabis.
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