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How To Grow Cannabis Using The Moon Cycle

While modern cannabis-growing techniques are becoming increasingly high-tech, many cultivators still rely on ancient wisdom to ensure the success of their plants. Growing cannabis in accordance with the moon, for instance, can increase both the health and yield of a crop, and while it might sound like hocus-pocus, the reality is that gardeners have been growing plants using the lunar cycle for thousands of years.

How Does The Moon Affect Cannabis?

The concept of using the moon to grow cannabis belongs to a school of thought known as biodynamics, which is based upon an alignment with nature’s rhythms in order to support agriculture. When applied correctly, biodynamics can reduce or even eliminate the need for fertilisers, pesticides and greenhouses, as it increases the speed at which plants grow while also boosting their resistance to pests and pathogens.

Like all plants, cannabis relies on water and nutrients from the soil, and the movement of these key ingredients is heavily influenced by the moon. Just as ocean tides oscillate in accordance with lunar cycles, so too does the ability of plants to utilise vital soil components.

Understanding The Lunar Cycle

The moon takes roughly 28 days to orbit the Earth, and the strength of its gravitational pull varies drastically as it passes through its different phases. At new moon, for instance, our rocky satellite sits in between the Earth and the sun, which means we can’t see it as only its far side is illuminated. However, because the Earth, moon and sun are all aligned at this point, the lunar gravitational pull is particularly strong.

From here on, the moon begins to wax as it moves out of the sun’s path, becoming bigger in the sky each night and casting more light onto the Earth – and all the cannabis plants growing down on the ground. After one week, the first quarter is reached, which is when half of the moon is illuminated. Its gravitational pull is also at its lowest during this phase.

At two weeks, we reach full moon, which is when the Earth sits between the sun and moon. Once again, the three celestial bodies are aligned at this point, which means that in addition to being at its brightest, the moon’s gravitational pull is also back to its maximum.

The final two weeks of the cycle are characterised by a waning moon, as it diminishes each night until it returns to the new moon position.

The lunar cycle. Image:

Taking Advantage Of The Moon To Grow Cannabis

The ability of cannabis plants to take up water and nutrients is influenced by the moon’s gravitational pull and the amount of light it casts. When this gravitational pull is at its strongest, water, nutrients and sap are dragged upwards from the roots into the leaves of a plant. At the same time, the more light reflected by the moon, the greater the ability of cannabis plants to utilise nutrients.

Conversely, when the moon exerts less gravity, fluids drop back into the soil, remaining in the roots. Because of this, the waxing moon is generally associated with more activity in the upper parts of a cannabis plant, while the waning moon is believed to promote the growth of roots.

All of this can be taken advantage of in order to boost cannabis growth. For instance, sowing seeds in the days leading up to full moon can speed up germination, as the upwards pull of the moon is strongest at this point, while water and nutrients are also highly available in the topsoil.

This is also a particularly good time to feed plants, as the moon’s gravitational pull ensures that nutrients are able to reach the upper leaves of a cannabis plant more efficiently.

The waning moon, meanwhile, is a good time to transplant cannabis seedlings, as roots are able to grow best during this phase of the lunar cycle. Pruning is also a good idea when the moon’s gravitational pull as it its lowest, as this ensures that most of the sap is in the roots rather than the leaves.

Harvesting cannabis using the moon always involves a bit of a trade-off. Some say it’s best to do so around full moon, as this is when the flowers contain the highest concentration of sap, thereby promoting terpene and cannabinoid production. However, it’s also when the amount of water in the upper parts of the plant is at its peak, which means drying and curing tend to take longer and mould infections become more likely.

For this reason, some growers believe it’s best to harvest during the waning moon, as dryer bud tends to result in less hassle.

How The Position Of The Moon Affects Cannabis Growth

In addition to passing though numerous phases, the moon also changes position in the sky as the month progresses, ascending for two weeks of each cycle and descending for the remaining 14 days.

Among biodynamic farmers, the ascending moon is described as being akin to an “in breath” for plants, as the lower position of the moon forces water and nutrients deeper underground, allowing for a decline in activity in the leaves and flowers. Conversely, the ascending moon acts as an “out breath”, when fluid is drawn up as the moon rises, generating a burst of growth in the upper parts of a cannabis plant.

When growing weed with the moon, therefore, it’s necessary to take into account both the phase of the lunar cycle and the position of the moon in the sky. While this may sound complicated, it’s actually pretty easy if you just remember that every increase in lunar gravity and light corresponds to greater activity in the above-ground parts of a plant, while less pull and illumination allow for growth below the ground.

Cultivation information, and media is given for those of our clients who live in countries where cannabis cultivation is decriminalised or legal, or to those that operate within a licensed model. We encourage all readers to be aware of their local laws and to ensure they do not break them.

This post is also available in: French

Ben Taub