Cannabis cloning

Cloning (grafting) is a vegetative way of propagating marijuana. Often on the forums you can find questions which is better: growing hemp from seeds or clones? Unlike propagation by seeds, where the genotypes of both parents are mixed in the offspring, clones are a 100% genetic copy of the mother plant. Thus, the grower can always have a guaranteed high-quality planting material, while also saving time – the stage of seed germination is completely excluded from the cycle, and the plants obtained by cloning go to the hemp flowering stage faster. The sex of the cuttings always corresponds to the sex of the mother plant.

Choosing a material for cloning

The ideal option would be a plant older than two months in the growing season. Cuttings from too young donors grow more slowly, and taken from flowering plants, although they root perfectly, can take up to a month to return to the growing season. Whether this plant is grown from a seed, or is itself a clone – it does not matter. Marijuana can be sequentially cloned many times, and each subsequent generation will be an exact genetic copy of the progenitor.

Both Indica and Sativa marijuana and their hybrids are equally good for grafting. Difficulties can arise when trying to clone varieties that include Ruderalis due to their autoflowering ability. Regardless of the species and variety, the mother plant must be strong and healthy, it must not be stressed. This also applies to the root system – healthy roots will be firm, bright white.

Preparing the mother plant

For better rooting of cuttings, it is desirable that their stems have a higher carbohydrate content and a lower nitrogen content. For this, leaching is used – watering the plant with clean water three to four days before cutting. In the leaves, the nitrogen content is reduced by spraying, also three to four days in the morning. In this case, signs of a lack of nitrogen may appear – the leaves will become lighter, and growth will slow down.

The most commonly used light regime for cannabis to maintain the mother plant in the growing season is 18/6, but a longer light period is possible, up to 24/0. With this kind of lighting, photoperiodic varieties can be grown for a long time without turning into flowering.

Older lower branches have the best rooting ability. During spilling, the core of their stems accumulates the largest amount of carbohydrates necessary for root growth, and it also contains the highest concentration of root hormones. A firm but easily bent branch is an indicator of a high carbohydrate content. The top of the plant is loaded with growth hormones that stimulate the formation of new leaves and shoots, and is less suitable for cloning than other parts of marijuana.

Cutting cuttings

Before starting work, tools, hands and work surfaces must be cleaned and disinfected to prevent mold, bacteria or viruses from contaminating hemp through the cut site. Alcohol, vinegar, or chlorine bleach can be used for this. Prepare everything you need before starting work, including a container with water for freshly cut clones – if the cut of a clone is exposed to air for a long time, bubbles form in its channels, which can lead to their blockage (embolism).

To select the location of the cut, it is necessary to count three or four internodes from the top. Cuttings are carefully cut with a sharp blade, at an angle of 45˚, without crushing the stem or softening it. Root growth will occur from the cambium layer just below the peel of the stem. To increase the area in which root sprouts can appear, you can split the end of the stem or cut the skin at the bottom.

Then the lower leaves are removed – this will reduce the consumption of moisture before the roots appear, and the plant needs photosynthetic products in a minimum amount at this stage. To prevent embolism, all operations that violate the integrity of the stem are best carried out in water, and the prepared cuttings should be immediately placed in a container with water.

Rooting clones
You can root cannabis clones in water, soil, or rock wool. In all of the above methods, it is appropriate to use biological additives (for example, Kornevit or Clonex) that stimulate root formation. The recommended temperature for marijuana is 22-23˚С, and the ambient temperature can be slightly higher – 24-27˚С. The pH value of water for irrigation is in the range of 5.0-6.0. Humidity from 95-100% in the first day or two, with a gradual decrease to 80-85% during the week.

To maintain stable conditions, it is recommended to use micro-steamers or tall boxes, covered with cling film on top. In the early days, clones require at least minimal ventilation and lighting with a light period of 18-24 hours a day. In this case, the light should not be too intense, you can use fluorescent lamps or ECL, and when illuminated with HPS lamps, the distance to rooting cuttings should be 1.2-1.8 meters.

In the first week, clones may look withering and unhealthy (a reaction to the severe stress they have endured and the need for a complete restructuring of all biochemical reactions), but gradually, as the primary roots grow, their condition will improve. After a couple of weeks, successfully rooted seedlings are ready for active growth. Those plants that remain sluggish and oppressed by this time, most likely, did not endure stress, and will recover for a very long time or even die altogether. Perhaps there is no point in messing with them anymore – they will still not be able to give a good harvest of cones.

In the third week, when the roots of the clone have grown enough to feed the plant (there is a tendency to active growth, new leaves and shoots are tied at the top), the seedling is planted in the soil or placed in a hydroponic plant. During this operation, you can simultaneously carry out the treatment with a fungicidal or miticidal solution, immersing the plant there completely.

Transplanting is stress for the cannabis, weakening the plant, it should be carried out as delicately as possible, disturbing the roots of the plant as little as possible. In the first couple of days, while the plant is recovering from stress, it needs to create mild, gentle conditions. The life processes of the plant, including photosynthesis, are slowed down at this moment, as well as the absorption of water and nutrients by the root system. Also, growers often make mistakes when replanting cannabis, which leads to extremely negative consequences. In order for the plant to better adapt to the changed conditions, it is better to move the seedlings in the evening, before dark, so that the plant has time to “get used to” in a new place before the onset of the light period and the beginning of active photosynthesis.

A newly transplanted plant requires less nitrogen and potassium and a higher phosphorus content. In the early days, while the metabolic processes of the plant are still slowed down, it is watered with a solution with half the norm of nutrients, but quickly transferred to good nutrition. At the same time, it will be timely to add Trichoderma to the soil or substrate. Now the process of cloning marijuana has come to an end, and the cannabis plant is ready for active vegetative growth and an early transition to the flowering stage.