Once you have followed all the correct steps to ensure healthy vegetative growth and vigorous flowering, the next step is to harvest your mature plants. This article provides a basic set of guidelines on when to harvest, how to harvest and what to do with your freshly-harvested flowers.
When should you harvest cannabis plants?
To harvest successfully, you should know the exact date that your plants started flowering. If you don’t know the exact date, then you should at least have an approximation. This knowledge will give you a rough idea of how long your plants will need to flower, and from that you can work out the approximate expected date that you will harvest.
Flowering times for cannabis vary greatly according to strain. Indica-dominant varieties generally finish early, in as little as seven or eight weeks after flowering begins, while sativa-dominant strains may require substantially longer—up to 24 weeks in some extreme cases. The majority do not require such long flowering times (10-12 weeks is generally the longest most growers are prepared to wait), and there are also numerous sativa-dominant commercial hybrids that will finish in under 10 weeks.
However, knowing the approximate requirements of your chosen strain may not be sufficient to judge whether your plants are ready for harvest. A useful technique is to assess the percentage of white hairs that have changed colour (usually to a brownish-orange, though some strains may have pinkish or purplish hairs). Plants should not be harvested until at least 40% of hairs have turned.
THC levels are often highest if harvesting when 40-70% of hairs have changed; if you continue to wait past this point, THC will begin to degrade to CBN. This may cause the effect of the finished flowers to be more soothing and less likely to induce anxiety. This process where THC degrades to CBN also occurs after harvesting and during decarboxylation.
It is also possible to assess maturity by using a magnifying glass to observe trichome colour. If clear, plants are immature; if cloudy, THC levels are at their maximum, and if amber, degradation has begun to occur.
How should you prepare yourself for the harvest?
Before commencing the harvest, ensure that you are equipped with the following:
- A pair of good quality rubber (powder free) or latex gloves
- A sharp, clean pair of scissors or shears
- A large plastic tray or tub in which to place cut branches
- Some twine or string you can use to attach your branches to hang and dry
- Something to hang the branches from, such as a clothes line, wardrobe dowel etc.
Note that the gloves will prevent sticky resin from adhering to your hands and will enable easier collection of the resin in case you want to make hashish. The blades of your cutting tool will also collect resin, which you can then scrape off and produce hashish. This is why it’s important that your scissors or shears are clean when you start using them!
It is better to cut branches separately to allow better airflow when drying, rather than keep plants whole
How to do the actual harvest?
When you are equipped and prepared, it’s time to start harvesting. How you cut your plants depends mainly on their size. If they are small, chopping them down at the main stem should be fine. However, if they are big and many-branched, it may be advisable to chop down each branch separately.
The main point to remember when cutting down your plants in preparation for drying is that care must be taken to avoid manhandling the flowers and potentially damaging them. It is also wise to ensure that sufficient airflow will be able to circulate around the flowers as they dry; separating the plant branch by branch should be enough to ensure this.
When you have cut your branches, place them gently on your plastic tray. Once all the branches have been cut from the plant, take pieces of twine or string and bind them to the branches close to the point where they were cut. You can hang them on the clothesline or whichever place you will be suspending them. Suspending them above the tray ensures that you catch any stray leaves that fall down during pruning or drying.
Once they are suspended, it’s time to prune off those big fan leaves. It is easier to do this when your plants are freshly cut down! Using your scissors, remove the large fan leaves. This allows more airflow to circulate around the buds. You can use these fan leaves for other reasons, but your buds won’t need them.
Pro tips for a successful harvest
- If your plants are outside, start early in the morning before the sun gets too hot.
- If you are too eager to wait for the perfect harvest moment and you’d like to get started earlier, start with the buds growing on the top half of the plant. These parts mature first and harvesting them doesn’t affect the rest of the plant. Harvest these and leave the rest to mature.
- The buds on the lower part of the plant have a slightly different colour composition. This is because they mature slower than the top half.
- Using a magnifying glass, you can assess the colour of the trichomes. If they are cloudy (rather than transparent), those buds are ready to harvest. In this moment, buds have the highest THC content. If your trichomes have turned amber, the THC levels have started to drop as THC is degraded into CBN (this might be desirable if you want a more gentle buzz from your buds).
- If you’re harvesting for the first time, try harvesting buds at different times. You’ll then be able to sample buds at different harvesting times and you’ll have a good idea for the future.
- When harvesting, try to keep big branches attached. You will appreciate the “Y” or “V” shape created by branches, as it makes hanging them up to dry much easier.
- Use good tools and take utmost care with your plants. Harvesting is just as important as growing and you don’t want to lose all of those delicious trichomes in the process.
How to dry your cannabis plants
If you want to ensure premium quality of your buds, then you must dry and cure them correctly. This stage has a significant effect on the final result of your harvest.
Drying takes place once your plants have been cut and the fan leaves have been removed. In order to dry successfully, the correct environmental conditions must be met:
- If it is too cool or damp, drying will occur too slowly and mould may form,
- If it is too hot or dry, flowers will dry too quickly and will develop a harsh, green taste when smoked,
- Flowers may also dry unevenly if it is too hot or dry, which will lead to them being crispy and dry on the outside but still damp inside.
The ideal setup for drying cannabis is to hang the branches from a clothes line or similar device situated in a room in which the temperature range stays at around 18-24°C (65-75°F) and the relative humidity remains at 45-55%. It is also necessary to ensure that your chosen drying spot is dark, as presence of light will lead to more rapid degradation of THC.
Hang your branches along the line, making sure that they do not touch each other as this will encourage retention of moisture and potential mould growth. Placing an oscillating fan on a low setting and allowing it to run throughout the drying period will improve airflow and reduce chances of mould growth occurring.
Plants will need to dry for at least 3-4 days before the curing stage, which we describe in detail a little later on in this article. Some growers will leave branches to hang for as long as 7-10 days, and may dispense with a set curing period altogether. Trial and error will help you to establish the best method for your individual setup and your chosen strain.
Pro tips for successful drying
- Examine your buds every day, looking for signs of mould or uneven drying. Detecting issues early helps you to fix them rapidly and before it’s too late.
- Drying too fast or too slow results in problems. This is why there is a recommended temperature and humidity. Drying too fast will end in a harsh smoke. Drying too slowly could result in mould appearing. Stay as close as possible to the recommended temperature and relative humidity.
How to cure your cannabis
The curing process is the final step of any cannabis cultivation – and it is just as important as any other step. Some newbie growers underrate the importance of curing. However, without curing properly, dried buds would not retain the depth of flavour and aroma. So curing is important to having a premium, well-rounded product at the end.
Fundamentally, curing is the process of achieving the perfect level of moisture in a dried herb. We all know that if it is too dry, it doesn’t smoke well. The same is true if it’s too moist. The curing stage is the process by which buds are left at a certain temperature and humidity, allowing them to retain the optimum amount of moisture. Essentially, this is the “preservation” method for cannabis.
The alternative is buds that are not tasty and possibly not effective! So to commence the curing process, follow these straightforward steps:
- Start the curing process by putting your buds in a plastic bag. Then put that plastic bag inside a paper bag. You’ve created a non-absorbing, light proof place to cure your buds. They can be cured in this way for a few days
- Check your buds every day. Move them around to distribute air evenly around the buds. If they are sweating, it’s fine! It’s what they are meant to do.
- After a few days, it’s time to transfer them into glass jars. This part of the curing process will preserve all of the flavours and keep the buds at the correct dry/moist level. Don’t pack the jars too tight, as it’s important that air circulates. It’s best if the glass jar is airtight.
- Every day, open the jar and move the buds around a little bit. This ensures the air in the jar is refreshed and allows your buds a chance to cure evenly.
- Some people cure their buds for months! If you’re very particular about flavour, aroma and the way the buds smoke, the curing process is extremely important. How long you choose to cure before smoking is up to you. Looking at them every day will give you the best idea of when they are ready to smoke.
As you finish harvesting, the indoor season begins!
So you have just harvested your outdoor crop. You have some nice cannabis buds to smoke over the winter. And of course, it is time to start the indoor season! The beauty of indoor growing is that you are not limited by cold European winters. You can still grow some great cannabis!
So don’t be disappointed that your harvest is over. It just means that it’s time to get shopping for some good indoor seeds from Sensi Seeds’ online store. You’ll be able to grow right through the winter, harvesting right before the spring, in time for another outdoor season!
Happy harvesting and cultivating to everyone!
- Disclaimer:Laws and regulations regarding cannabis cultivation differ from country to country. Sensi Seeds therefore strongly advises you to check your local laws and regulations. Do not act in conflict with the law.