The flowering stage seems to be coming to an end and you are eager to harvest your plants as soon as possible. Harvesting is a crucial moment in cannabis cultivation. It is very common for beginners to get too ahead and try to chop their plants too early. The plant gives signals for us to know exactly when she’s ready to harvest.
Before Harvesting a Cannabis plant
Prepare your plants
Check for pests and discard damaged parts (fungi, severe insect infestation).
Cut out big fan leaves, especially if they had pests.
Flushing: When growing with mineral nutrients, flushing is recommended. Start 2 weeks before harvesting.
Flushing Cannabis plants before harvest
Flushing a Cannabis plant is basically running a lot of water through its growing medium (soil, for example) to get rid of the excess salt and mineral nutrients. This action forces your plant to use up any amount of nutrients previously absorbed. The result will be buds with better flavor and aroma. The excess fertilizer in your Cannabis plant may result in buds that are harsh to the throat when smoked.
Flushing with clean, room temperature water will help to get rid of fertilizer excess in the soil.
How to flush your indoor Cannabis plants
Place a container (bucket or similar) under the pot for collecting the excess water, be careful or this may result in a bit of a mess.
Two weeks before harvesting is usually a good moment to start flushing your plants and watering with water only and no fertilizers until the harvesting moment. You can water with 10%-20% more water than usual and see how your plants react, they shouldn’t look droopy and should recover soon. The excess water will slowly drain from the bottom of the pot.
A good visual sign is that, in the beginning, the water coming from the bottom of the pot will be dark and will gradually turn to a lighter color. By running this process once in each plant, most of the salt buildup should flush away from the substrate. Discard the runoff water.
Even though lots of fertilizer companies recommend flushing plants for two weeks before harvesting, many growers nowadays choose to avoid flushing altogether and still have good results. It’s a matter of personal choice and one must evaluate the growing conditions, the nutrient schedule, and the final results.
When to stop fertilizing before harvest
Two weeks before harvesting is usually a good moment to start flushing your plants and watering with water only (no fertilizers) until the harvesting moment.
When to stop watering before harvest
Depending on the size of the pot, you can stop watering 1-3 days before harvesting.
Cannabis plant near harvesting date.
Prepare your drying space
Darkroom or tent
Temperature: Around 20º C
Relative humidity: 50%
When to harvest your Cannabis plants
Cannabis strains have their own particular flowering time, which may go from 8-12 weeks for most breed hybrids, and even less in the case of fast auto-flowering strains. It is important to use this information as a guide to starting checking our plants, but dates may vary along with cultivation methods, environmental factors, etc. When the harvesting date approaches, it is recommended to start checking the buds for pistils and trichomes ripeness to determine the best harvesting moment.
To know when to harvest we’ll look at pistils and trichomes:
Pistils are those little “hairs.” They start white and as the plant ripens, they get darker and curling until they are brown. Trichomes are little resin glands (that “frost”) and they also change color as they ripen. They look like little lollipops.
How to tell if your plant is ready to harvest
A simple way to determine harvesting time is to look at pistils’ evolution. Pistils start as a pair of white hairs and they start grouping to make the buds. – Buds with white pistils sticking out are very young. Don’t harvest yet! – After that, pistils start turning orange, brown, or even pink and they stay “upright”. – When harvesting time is near, there’s a majority of orange or brown pistils and they have curled inwards the buds. This may also happen due to environmental factors even when the Cannabis plant is not yet ready for harvesting. It’s a good indicator to start looking at the trichomes: that’s the perfect way to know if the plant is ready.
You can see and track these changes without any equipment, just observation by the naked eye.
The best way to determine Cannabis harvesting time is given by the trichomes.
Trichomes are little resin glands and they also change color as they ripen. They look like little “lollipops” sticking out – Trichomes start clear and transparent. and some days later they turn milky white.
When trichomes become milky-white and some of them are amber, that’s the best time to harvest.
If the trichomes are all amber / brown, it’s probably too late!
Look at the trichomes with a magnifying glass or loupe and their color will tell you the best moment to harvest. In this photo, trichomes are already milky white and pistils are orange. Ready to harvest!
When to harvest looking at Pistils
50% brown 50% white pistils – young, light marijuana
70-90% brown/orange – ripe marijuana
90-100% brown – sharp, heavy marijuana
When to harvest looking at Trichomes
How to check trichomes: with a magnifying glass or microscope
Clear trichomes – wait a bit longer
Milky trichomes – near harvest
All Amber trichomes – overripe
We prefer to look at the trichome evolution because it’s a more accurate method. Pistils may change color because of environmental modifications such as high humidity and not necessarily because the plant is ready to harvest.
How to harvest a Cannabis plant step by step
Shears or scissors
Isopropyl alcohol or alcohol 70% (to clean your tools)
Plastic gloves (it gets messy and sticky)
Plastic tray to put branches
A drying rack / box / tent / hangers
Before starting, set your workplace. Clean your tools and hands, wear plastic gloves when touching the plant, and keep rubbing alcohol on your tools if it gets too sticky.
According to the plant’s size 1 hour.
How to harvest a Cannabis plant indoors
Cut the plant and its branches - Depending on your plant’s size, cut out all the branches first or cut the plant at its base and then cut out the branches one by one. Cut out big fan leaves, especially if they show signs of pests (insects, mold, fungi). Place those branches in plastic trays.
Divide branches into buds - Divide the branches into smaller twigs or individual buds. Depending on the size of the buds and the relative humidity of your drying space, you can leave them bigger or smaller. Work on a clean surface like a big table and be tidy.
Dry in a dark ventilated place - Make sure the room is dark and the exhaust fan is running if drying in a tent. If the buds are laying on a surface like a drying rack, rotate them every now and then so they keep their shape. Drying may take 10-14 days.
Trimming buds before or after drying - You can trim or keep the sugar leaves with trichomes if desired. This step may be done before or after drying.
Curing: put buds in jars - When the drying process is ready (10-14 days), put your buds in sealed jars, and start the curing process. You can also weigh your yield before curing, as most of the moisture in the buds will have disappeared by then. For the first 2 weeks of curing, open the jars once a day for an hour, and seal them after. This process may take from 3 weeks to months.
Don’t forget to tag your jars with strain and harvesting/curing dates! You can log information such as harvesting dates and weights in the Grow with Jane tracking app!
Harvesting is a great moment in every grower’s journey. Now you know how to tell when are buds ready to harvest and how to do it. If you have more questions, please tell us in the comments. We hope you have a great harvest and soon be enjoying your own!
Congratulations on your harvest!
How to dry Marijuana
There are many ways of drying Cannabis after harvesting: using drying racks, and boxes, hanging the individual branches or hanging the whole plant to dry upside-down with a wire or similar.
Turn on a fan and aim it right beneath the buds if there’s no airflow. Make sure the room is dark, and the exhaust fan is running if drying in the growing tent. Keep humidity around 50% and the temperature around 20º C. The drying process may last 10 and 14 days. Look at them every day and make sure no mold is growing. If you find some, cut that bud and throw it away before it grows all over your buds.
How to cure Marijuana
To cure your Cannabis buds, keep them in glass jars or similar and open it once a day until they are cured. Exposure to oxygen and light causes THC degradation. To protect your precious buds, keep them in sealed containers, in a dark place. Temperature around 20ºC Humidity 58%-65%