Saturday, August 1, 2020

When to Harvest Cannabis for Greatest Potency and Aroma

Cannabis terpenes are synthesized (manufactured) in the cytoplasm of the cells of the trichome head (TH) via the Mevalonic Acid pathway (MEV), and in plastids via the Methyl-Erythritol Phosphate pathway (MEP) . Monoterpenes, such as the pinenes (1), limonene, terpinolene and myrcene are a result of the MEV, while large terpenes like caryophyllene, farnesene and humulene are derived from the MEP. As the plant synthesizes more and more of the enzymes of terpene synthesis during flower, it makes perfect sense that their aroma becomes more prevalent and more precisely developed as the TH ripen.

Cannabinoids reach maximum concentration in the ninth week of flower (Aizpurua-Olaizola, et al, 2016). This is not a precise measurement, but rather a guide. Most growers believe harvest should take place whenever the TH become opaque and white, which is usually during the ninth week as molecules inside the TH pass their saturation point. Careful inspection and a watchful eye will notice the whiteness of TH without any need for magnification.

Simply keeping up with the number of flowering days elapsed will accurately hit this peak of cannabinoid concentration every time. There’s no need to break out the hand-held microscope and inspect flowers. Keep in mind that individual grow lights may be stronger or weaker than one’s flowers can tolerate, so results will vary. Nine weeks is sixty-three days.  Cannabis plants should generally be harvested on day 63 of the flowering phase, when cannabinoid concentration is at or near its maximum to begin preserving the flower in this optimum composition.

Some plants require a longer flowering period, sometimes up to thirteen weeks, to mature (e.g. Laughing Buddha). Once a plant’s maturation period is established for your conditions, that number of days can be relied upon. It is written in the plant’s genetics and there is no escape. 🌂

Aizpurua-Olaizola, O., Soydaner, U., Öztürk, E., Schibano, D., Simsir, Y., Navarro, P., ... & Usobiaga, A. (2016). Evolution of the cannabinoid and terpene content during the growth of Cannabis sativa plants from different chemotypes. Journal of natural products, 79(2), 324-331.

1.    For the sake of brevity and to avoid confusion, terpenes are here named without prefixes such as "alpha" and "beta", as well as without chirality indications such the "d" prefix of d-Limonene.


Guest article by Leeanne Brooks

Growing cannabis is becoming a lucrative industry now that so many states and countries have lifted their ban on the plant. New farmers, however, will find it difficult to know when the flowering stage begins and when to harvest the plant. Below are a few tips on what to do during the flowering stage of cannabis.

Maintaining during flowering

Before the plants even get to their flowering stage, you should make sure that all plants are green, lush, and healthy. There shouldn't be any discolorations on the leaves because of a lack of nitrogen, nor should there be any signs of stress on the plants itself. If you notice any abnormalities, try to nurse the plant back to health before moving forward with the flowering stage.

If you've been giving the plant nutrients, make sure that you include a flowering formula during the first month of flowering. Try not to change the nutrient solution until you notice the plants develop plenty of pistils.

Using the right nutrients

During the flowering stage, the kind of nutrient that you give your plants will have to change. During this stage, it's important that the plants receive a lot of phosphorus and potassium to support the many changes they are undergoing. But keep in mind that before you change the fertilizers, ensure that plants are about to start flowering.

Use the flowering formula only in the first month of flowering. This stage will also require you to pay close attention to the plants to watch out for diseases and pest infestation which the plants are very prone to during this stage in their development.

Don't overfeed

It is during the last two weeks of the flowering stage where you should stop feeding plants nutrients. At this stage, the plants will start shedding some of their leaves. This happens because of the shift in the plant's allocation of energy from making food into developing buds. Signs that you're overfeeding are discoloration or leaves are being shed at a faster rate.

Train the plant

Training the plant means you help them maximize the use of the space in which they're growing to increase the yields. This applies especially if you are growing your cannabis indoors. Training is usually done during the first month of the flowering stage.

The cannabis plant has a flexible stem that is easy to manipulate once the plant enters its flowering stage. As they mature, the stems become more woody and difficult to train.

Supporting the plants

During the second month of flowering, the plant will start getting ready for harvest. They start to become thicker and develop more buds. The transparent resin on the leaves will start to darken and release a pungent odor. At this stage, the plants will require more support due to their weight. Set up a trellis system of strings and wires to give the plants more support.

Growing room conditions

If you're growing your cannabis indoors, it is during the flowering stage that you need to make sure that the conditions in the growing room are optimal. Since the plants are now growing closer together, you have to adjust the humidity and temperature to stop the plants from developing diseases and fungi.

Make sure that the temperature sits between 68 and 77 degrees Fahrenheit at the leaves and 68 degrees Fahrenheit at the roots. Once the plants are in their second month of flowering, you can drop the temperature several degrees so the buds produce more resin.

Monitor the pH levels

pH levels range from very acidic (0, 1, 2) to very basic (14)

If the pH levels of the soils are not right, your plants could suffer some damages leading to tainted products no reputable dispensaries will accept. Some common signs that the pH level is wrong is when you start seeing curly or wrinkly leaves on your plants. The perfect pH level of soil fit for growing cannabis is between 6.0 and 7.0. If however, you are using a hydroponic system, the pH level should be between 5.5 and 6.5.

Knowing when to harvest

The flowering stage of cannabis plants will vary depending on the strain you are growing but will typically last around two months. The moment the calyces and pistils start to swell and turn red, the plant is ready for harvest.

The plant will continue to accumulate resin and flowering tops will become stickier and heavier. Because of this, the flowers may need support and may appear to move closer together. At this stage, you must have your carbon filters up since the smell emanating from the buds may attract unwanted attention from the neighbors. 🌂

Leanne Brooks is a passionate blogger who loves to write about innovative ideas on promoting mental and physical health for companies like GreenSociety, a licensed Medical Marijuana dispensary delivering premium quality cannabis to Canadian MMJ patients with online ordering.

Thank you, Canadian MMJ patients. Your purchase from GreenSociety supports Seattle Bliss via this affiliate link: Click to visit the GreenSociety website

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