They are called rooting hormones or phytohormones, and they are one more category in the list of fertilizers and agricultural inputs that we can use to improve the development of our plants.
Although most of them focus on professional farming, there is a niche market accessible to any gardener, called rooting hormones.
These substances are able to act directly on the basic processes of cell division and fattening, creating rapid plant changes when combined with nutrients.
In this article, we focus on the phytohormones used to cause cuttings and stems to quickly root, making it easier and faster to cut and transplant any tree or plant.
How Rooting Hormones Work
The main phytohormones that have an activity on root production in cuttings and stakes are auxin nature (auxins). Among them, we can find those obtained naturally (indoleacetic acid) or obtained by synthesis, such as indolebutyric acid.
Various tests have shown that synthetic auxins have a greater effect on root generation compared to natural ones.
Certain rooting hormones such as indole butyric acid cause the cell mass differentiation known as calluses. These calluses are clusters of thousands of undifferentiated cells. Stimulation of this compound causes them to form tissues in the form of roots.
Rooting of cuttings
When we get stakes or cuttings without root formation, the use of this type of rooting hormone encourages any bud at the base of the cutting or stake to start emitting absorbent white hairs.
This emission can be obtained naturally with humidity (immersion of a cutting in water or in a well hydrated substrate), but with this rooting hormone the process is accelerated and the the success rate increases dramatically.
Types of Rooting Hormones
The main rooting hormones that we can use to increase root emission are of auxin origin, as we mentioned earlier. Let’s analyze the main ones:
Indole butyric acid (IBA)
Indolebutyric acid is obtained from indoleacetic acid. Although it is classified as a synthetic hormone, some studies suggest that it can be found naturally in certain plants, although it is not known for certain whether it comes from a transformation of indoleacetic acid (IAA).
Indole butyric acid (IBA) is the primary rooting hormone, used alone or in combination with other rooting hormones and products.
Indoleacetic acid (IAA)
Indoleacetic acid (IAA) is one of the best-known rooting hormones used in agriculture, mainly due to its natural origin and its presence in different types of algae.
Applied both in irrigation and foliar, it moves at high speed (7.5 mm/h) towards the roots (basipetal movement), increasing the formation of lateral and adventitious roots.
Its effectiveness in stimulating root formation is considered to be slightly lower than that of the previous rooting hormone, indole butyric acid (IBA).
Naphthalacetic acid (ANA)
Naphthalacetic acid (ANA) is another hormone of synthetic origin, made from the hydrolysis of 1-naphthalene acetonitrile. It is often used in conjunction with indole butyric acid (IBA) to create highly effective commercial rooting agents.
In fact, one of the most used products is the mixture of the two synthetic auxins.
How to Use Rooting Hormones
If we are looking for products designed for the formation of roots in cuttings and cuttings, those that generate the greatest effectiveness are those that contain the aforementioned hormones, alone or mixed with other nutrients and components.
However, you will find many products online associated with this type of substance but do not declare them, so they can generate doubts in your purchase.
Most successful commercial formulas for these rooting hormones:
- Formula 1: 0.1-0.2% ANA (naphthalacetic acid) + 0.05% IBA (indole butyric acid)
- Formula 2: Indolebutyric Acid 0.33%
These products are in the form of a gel, so their application is very comfortable. There is no need to pre-dilute or measure product weight or volume. The gel is applied as it is on the base of the stakes or cuttings, distributed evenly and without leaving sticky points or exposed surfaces in the first centimeters of the base.
For an ideal distribution of the product, we can also use a brush, carefully wetting the entire base of the cutting, and immediately after we plant the cutting in a pot with a previously hydrated substrate.
Avoid inserting the cutting or cutting directly into the bottle of hormonal product, as the humidity of the plant can reduce the future effectiveness of the product or reduce its expiry date. The idea is to scoop out some of the gel with a spoon or stick and take it to another container before spreading it at the base of the plant.
How to Get Homemade Rooting Hormones
If we have no way to obtain the rooting hormones described above, we can also resort to other homemade options. Less effective, but they can get us out of trouble if necessary.
Freshly sprouted lentils are rich in natural auxins (mainly indoleacetic acid), so if we use the lentil sprout grinding syrup, we can use it as a homemade rooting agent.
Its power is, logically, much more limited than commercial rooting products, but it can help us promote root production in a much more natural and ecological way.
The willow and various plants of the genus Salixlike weeping willow, contains a natural compound that promotes root growth, known as rhizocalin.
To prepare this liquid, a simple procedure consists of:
- Willow branches cut to 1 cm.
- Cook at low temperature in water for 10 minutes.
- Let the mixture sit for 24 hours.
- Straining the liquid is what we will use as a rooting agent.
Seaweed is known to contain different natural compounds and different phytohormones (auxins, gibberellins, cytokinins, salicylic acid, jasmonates, etc.) and polyamines.
Used in fertigation or by immersing the plant for 10 minutes in a dilution, very positive results are obtained.
Some of the most commonly used algae commercially are:
It is considered that the greatest rooting action is carried out by a relationship of hormones with a predominance of auxins over cytokinins.