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Magnifying Your Harvesting Skills

August 3, 2016

When harvesting approaches for your cannabis crop, it’s important to know exactly when to cut your plants. Knowing this is crucial to overall taste, density and potency, and attention to detail and patience are top priorities.

A must-have in every professional grower’s box of tools is a handheld microscope. This tool takes the guesswork out of knowing when it’s time to harvest. Counting the days and watching your plants from both a visual and microscopic point of view give you a near-estimate of when to cut. But the ultimate reality is in the color of the trichomes. Trichomes are what many refer to as the crystals or resin on the bud, and they are best observed under magnification.

One thing to consider is that the top part of the plant will finish before the bottom part. The middle branches are the average for the whole plant. This difference in location will help get a more appropriate judge of the condition of the overall plants and their readiness to harvest.

Ready for harvest?

Using your handheld field microscope, choose a bud on a central branch. You are looking for the trichomes and their shape and color. These will have the basic shape of a mushroom and be clear during early development. There should be no harvesting when the trichomes are clear; they are not ready. The white hairs (or pistils) on the plant are essential to bud growth and will shorten and change color as the cycle passes from early flower formation to creating buds.

During the second stages of the finishing process, the trichomes will begin to get cloudy. Clear trichomes are healthy through the entire grow, since the plant is always making new ones.

If you harvest when most (70 percent or more) of the buds are cloudy, they will have a more energetic high. This peak cloudy time is when the THC is most potent. This dynamic property is a bit stronger when you are harvesting sativas, which are a naturally energetic strain. You will lose some weight and density if you crop at this point; the amount will vary depending on strain genetics and growing style.

During the third and final stages of finishing, the trichomes will turn amber; the best practice is to wait until 70 percent of them are amber. The amber-colored resin indicates that the THC has reached the peak of ripeness and is ready to come down. These buds will produce the densest flowers, and may take a little longer. The more amber trichomes on your flower when you harvest, the more sedative and “couch-lock” effect the flower will have, after curing properly.


Amber and cloudy trichomes, ready to harvest (Photo: Analytical 360)

Some growers will harvest the top of the plant when it has finished and leave the lower branches to finish further. These lower branches might take for a few more days, even a week to complete. This extra waiting period is a more viable option for outdoor growers. Indoor grows can take some extra room and will cost more in electricity. It’s best to wait for the entire plant to finish fully and harvest all at once. This approach will be a personal choice for each grower.

Being patient is a challenge

Knowing when to harvest is easy; being patient is sometimes the challenge. But patience can pay off significantly, since your plants tend to put on more weight in the last 10-20 days. This weight gain is due to a hormonal response to the natural end of the flowering lifespan of the plant.


The bud’s last days, filling in faster and denser; your scope is very important at this stage. (Photo: eStonePhoto)

As a by-product of waiting, the plant’s natural desire to find pollen creates denser more potent buds for you. Essentially, the plant is still hoping to be fertilized by male pollen as long as it can. As it senses the end of the season, it will focus its energy on making the flowers more easily pollinated by adding density and “stickiness.” It adds more trichomes in hopes of catching just one floating male pollen, thus completing the cycle.

Patience is a virtue in the final days of finishing. For outdoor growers, the countdown to harvest starts when you see the first female pistils, which indicate female bud development.

Some indoor growers count the days from the day they switch the lights from vegetative to flowering, while others wait and count from Day 1 of flowering, which is the first day pistils are seen. The best practice for indoor or outdoor grows is to wait until you see the first sign of bud development and mark your calendar from that point.

Sativas take longer to finish than indicas, and hybrids will be dependent on the dominant variety. Each type of cannabis has a recommended approximate finishing time. Keep a calendar, but use your eyes and a handheld scope, as well as count the number of days. When in doubt, wait another few days at least.


By Eric Stone
Cannabis Cultivation Today articles are for informational purposes only and should not be considered legal guidance or advice on grow practices. You should contact an attorney or a qualified cultivation consultant for specific compliance and cultivation advice.


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