Trimming a cannabis plant after harvest

Harvesting Cannabis Plants Indoors

There is nothing more exciting than when harvest day is upon us. As growers, this is the time when all our hard work, investment, labour and skill pays off. Below I explain when to harvest and what to look out for, dry and wet trimming, the dry room and other things to consider.

The Harvest Window

Following a seed packets harvest date or paying attention to how many brown hairs are present on your plant are not ideal when harvesting cannabis plants. There are a number of factors that should be taken into consideration as well and they are:

Density and Biomass – This refers to the thickness of the buds and how dense their structure is. The calyx of a flower will swell in size as it becomes close to ripeness and maturity, meaning to touch there is a hardness that can be squeezed without damaging the flower.

The Fragrance – Your cannabis plants should be at the most aromatic towards the last few days of harvesting. All of the terpenes are at their most volatile and the aroma the plants give should be the loudest they can be.

Pistil Colour – The once white pistils that your plants produce should mature with an amber red and maroon colour. As plants reach the end of their flowering cycle, up to 90% of the pistils will change colour and begin to fall and wrap themselves around the calyxes. The colour of the pistils is just one of many variables to consider and should never be used to judge an imminent harvest date.

Trichome Production – In order to inspect your trichomes you will need to use either a magnifying glass, or macro camera to get close enough to check. Up close, the resin gland will contain all of the cannabis plants essential terpenes and cannabinoids, which means that in the trichome head you will be able to identify the maturity of the resin gland. You will see the heads change from clear white to a golden amber.

When Should I Stop Watering?

As you get closer to the end of the harvest date, the only time you should be feeding the plants on water is when flushing excess nutrients and salts out of the growing medium. Normally this is performed during the last two weeks prior to harvest.

Over watering plants should be avoided at the end of the plant’s life cycle and will only take longer for plants to dry out after harvest. I personally allow a 3-5 day dry period after my final watering to allow the medium to fully dry.

Wet Trimming VS Dry Trimming

There are two ways to harvest and trim cannabis, it is down to personal preference or practicality which you choose. Every grower at every level has their own method when trimming and drying flowers and both have their advantages over each other.

Wet trimming means to trim the plants the moment the flowering cycle has ended, meaning that they are not given a chance to dry out beforehand. Usually performed by growers who have small sized crops and are able to maintain the same level of consistency from start until finish.

The Drying Room

How you dry your buds can be a huge difference maker between the final smell, taste and overall experience. Speed drying can be a fatal mistake that can ruin an entire crop no matter how good the quality was prior to drying. After a flower has dried, up to 80% of the original weight will be lost, so to grow a kilo of dry flower requires five kilos wet.

When setting up a drying room be conscious of several things from odour control, the temperature and humidity, air movement, lighting and time frame. The temperatures of a drying room should never be warm and aiming for a cooler temperature of 15 degrees Celsius and a relative humidity of 50% will produce the most aromatic flowers possible.

The only air flow that should present is a gentle breeze blowing away from the buds and to circulate the air flow. An excellent solution to a smell proof drying room is using a grow tent with the carbon filter and extractor.

Your flowers will need to kept in darkness between 10-14 days before they can be smoked no matter how much of a demand there is to sell them or smoke them. Flowers that have been dried within a time-frame of 3-5 days will be much poorer in the final bag appeal and first impressions. So, have patience when drying flowers as being overzealous can have severe consequences.

The Curing Process

Once your flowers have spent up to 14 days in the temperature controlled, dark drying room, they will be dry to touch and when handling the buds. You should hear and audible snap like a twig breaking open. The concept behind curing is to dry in the inner parts of the flower to a point of ultimate stickiness, taste, and overall effect.

Glass mason jars, plastic tubs or any plastic container can be used, however must be air tight. Over a daily period, you will open the jars containing the dried flowers and allow them to sit for ten minutes before closing the lid and placing away out of direct sunlight until the same procedure tomorrow. Curing Cannabis can actually increase potency, convert THC into CBD as well as enhance flavour.

A Step by Step Guide to Harvesting

Before you start trimming it is a good idea to prepare in advance. A clean, sterile pair of scissors, latex gloves, music, snacks, drinks and pre-rolled joints always go down well for keeping motivation up.

STEP 1: Remove all of the fan leaves off the plant and discard to the rubbish. You will be left with only resin producing flowers and sugar leaf. The fan leaves are useless and cannot be used for making hash or isolator.

Lower Flower from Main Stem
2- A lower flower that has been cut off the main stem and can be trimmed

STEP 2: Carefully cut away all of the bud sites from in between the internodes of the branches and separate the entire branch from the individual flower. This should promote consistency in size and quality of the buds.

Cannabis plant Sugar leaves
3- Carefully cut away all of the smaller leaves around the buds

STEP 3: By gently holding the bottom of the twigs, using a clean pair of scissors, cut away the leaves that are heavily covered in trichomes without damaging the flowers. Avoid handling the flowers as little as possible keeping the trichomes intact. If you are making hash or extracts then collect all of the sugar leaf and lower buds into a separate bag or tub.

Well trimmed marijuana flower
4- A well trimmed flower

STEP 4: Once you have cut the flowers down to size and removed as much leaf matter as possible, you can now carefully insert the flowers into a drying net.

STEP 5: Set the dry room be to 15 degrees celsius and 50% humidity, with a mild breeze blowing away from the plants. The flowers will stay in darkness in the drying room from 10-14 days until the flowers are dry on the outside.

STEP 6: Place the dried buds into curing jars which can be labelled and dated as a reference to the curing time and strain name. The jars should be opened for 10 minutes per day to allow the air to be exchanged in the jar.

What’s your trimming method? Leave a comment below.