What fertilizers does marijuana need at different stages of growth?

Marijuana, like any plant, goes through several key stages of development: from seed germination to flowering and harvest ripening. At each stage, the crop requires a specific approach to nutrition. The correct selection and use of fertilizers for marijuana allows you to lay a solid foundation for growth and increase the chances of a bountiful harvest.

The influence of marijuana growth stages on fertilizer selection

If a grower decides to buy feminized cannabis seeds, they have already taken a step towards high yields, as these seeds produce predominantly female plants — those that form fragrant and THC-rich buds. However, even genetically strong plants require careful attention to nutrition, especially in the early stages of life.

Immediately after germination and the appearance of the first leaves, marijuana does not require abundant feeding. In the early stages, the plant feeds on the internal resources of the seed. At this point, it is better to avoid oversaturation: an excess of even beneficial substances can damage the delicate roots. Organic fertilizers for marijuana with a minimum concentration of nutrients or special solutions for seedlings are suitable as a starting solution.

In addition to the main elements — nitrogen, phosphorus, and potassium, known as NPK for cannabis — it is important to consider micronutrients for hemp, including calcium, boron, copper, and zinc. These substances are necessary for the formation of a healthy root system, strengthening of the stem, and normal photosynthesis.

Thus, even before the onset of vegetation, it is important to correctly assess the needs of the plant and begin to form a competent nutrition plan appropriate to its biological age. This lays the foundation for sustainable development at all subsequent stages.

Feeding marijuana during the vegetative stage

The vegetation stage is when the plant is growing like crazy, forming its stem, leaves, and future bush skeleton. At this point, it's super important to give your marijuana balanced and powerful nutrition so it can grow strong and get ready to flower. The right fertilizers for marijuana vegetation during this period are the key to plant health and the basis for the future harvest.

The main element needed for vegetation is nitrogen (N). It is responsible for the growth of green mass and also participates in the process of photosynthesis. However, it is important not to forget about phosphorus (P) and potassium (K), which strengthen the root system and make plants more resistant to stress. This is especially important if the temperature and humidity during cannabis cultivation exceed the optimal levels.

Here are the main recommendations from experienced growers on nutrition during the vegetative phase:

1. Choose fertilizers with a high nitrogen content. The ideal NPK ratio at this stage is approximately 3-1-2 or 2-1-2. This can be either a mineral formula or organic fertilizers for marijuana.
2. Fertilize regularly. On average, plants require nutrients 1–2 times a week, depending on the growing medium (soil, coconut, hydroponics).
3. Add micronutrients. In addition to basic nutrition, the plant needs calcium, magnesium, and sulfur. A deficiency of these elements can slow growth or cause leaf deformation.
4. Monitor pH and EC. The ideal pH level for soil cultivation is 6.0–6.5. For hydroponics, it is 5.5–6.0. This ensures proper nutrient absorption.
5. Consider the surrounding conditions. Temperature and humidity when growing cannabis directly affect the plant's ability to absorb fertilizers. The optimal temperature is 22–28 °C during the day and no lower than 18 °C at night. Humidity should be 50–70% during the vegetation stage.

It is also important to take care of marijuana during vegetation—control the light regime, perform formative pruning (if necessary), and monitor the overall condition of the bush. By using the best fertilizers for marijuana and following a feeding schedule, the grower will ensure that the plants have a powerful vegetative phase and prepare them for abundant flowering.

Feeding marijuana during the flowering stage

The flowering phase is one of the most critical stages in cannabis cultivation. During this period, the plant reorganizes its nutrition, focusing on forming dense, aromatic, and resin-rich buds. Properly selected fertilizers for marijuana flowering will help maximize yield and quality.

Unlike the vegetative stage, elements such as phosphorus (P) and potassium (K) are important during the flowering stage, as they stimulate flower development and increase their resistance to disease. At the same time, the nitrogen content must be significantly reduced to avoid excessive leaf growth and poor bud formation.

If a grower plans to buy autoflowering marijuana seeds, they should keep in mind that such plants often have a short life cycle and require precise and balanced nutrition appropriate for their rapid transitions between growth phases.

Below is a table with basic recommendations for fertilizer composition at different stages of flowering.:

During the flowering stage, it is also important to consider using organic fertilizers for marijuana with natural micronutrients, which improve the taste and aroma of the final harvest. Regular fertilization according to a schedule allows you to keep the plants in optimal condition.

Don't forget about proper cannabis care during the flowering period: control temperature and humidity, keep the grow box clean, and remove dead leaves in a timely manner. All this will create the ideal conditions for a high-quality harvest.

Attention! Sunny Seeds does not encourage you to grow cannabis and does not promote it in any way. Growing cannabis is prohibited by Ukrainian law. This article is intended solely for scientific and informational purposes.