Do you know your NPK ratios for growing weed?

The task of feeding cannabis plants is seemingly simple. Despite this, one of the most common problems that novice growers face is a poor fertilization schedule. Additionally, you may be surprised to hear that overfeeding is more common with these plants than underfeeding.

Nonetheless, knowledge is power. Understanding the required NPK ratios for different stages of a cannabis plant’s life cycle will give you the tools to effectively manage the health and yield of your crop. Nutrients are an essential factor in cannabis cultivation. The triad of macronutrients nitrogen (N), phosphorus (P), and potassium (K) are the stimulants used by most other plants and marijuana for development.

The base nutrients in NPK cannot be applied to the soil in the same ratio for the entire cannabis life cycle. Depending on the particular processes for which the plant provides energy, the required concentrations vary.

Cannabis NPK fertilizer application ratios based on growth stage

Fertilizing is more than just putting the nutrients in the substrate and watching your plant grow. Different stages in a cannabis plant’s life cycle require different NPK ratios for ideal results.

seedling stage

Even if this phase is associated with many difficulties, fertilization is not one of them. Any healthy soil should contain all the nutrients a seedling needs to grow well, and adding extra nutrients through fertilizer will send the seedling to an early grave rather than help it. Don’t get too excited at this point; it must be left alone most of the time!

What to do in the vegetative phase

Upon entering the vegetative phase, the plant begins to crave nutrients. During this vegetative state, the cannabis plant requires a 3:1:1 NPK ratio. However, that doesn’t necessarily mean you need to feed the plant a fertilizer that has that ratio.

Many soils are rich in nitrogen, enough to support the first four weeks of vegetative growth, so you should reconfigure your nutrient solution based on the substrate’s current NPK ratio. A tiny nutrient deficiency is far better than too much. For this reason, you should always play it safe. If you have healthy soil, a 1:1:1 fertilizer will probably do the trick. Simply put, this means that each macronutrient is present in equal amounts.

flowering phase

As cannabis plants progress from vegetative to flowering, their macronutrient needs shift in the opposite direction. Switching to base bloom nutrients and manipulating the NPK ratio would help. For early to mid bloom, a highly effective NPK ratio is 1:3:2, followed by 0:3:3 for late bloom. Then a final rinse with light and/or pure water rinse solution at the end of the last week for taste. After that, the harvest begins.

Your buds will grow in quantity and size according to the P and K (Phosphorus and Potassium) commands. For this reason, the main goal of growers is to reduce nitrogen levels while increasing P and K. Excessive addition of nitrogen late in flowering spoils the sinsemilla. The buds will taste harsh and they just won’t smoke as smoothly as a fully flushed stash. Skip nitrogen entirely for the last 20–30 days.

Using NPK fertilizer to grow cannabis

As previously mentioned, soil growers do not need to add fertilizer during the seedling stage. Usually it is enough to add beneficial microorganisms and enzymes to the soil. These support root development and make nutrients readily available in the soil. Some strains, especially the indica strains, tend to respond better to higher doses of fertilizer; a higher level of sativa presence relates to lower nutrient requirements. Hybrids take the middle ground, with some tending toward a preference for stronger or lighter doses.

Direct exposure to indoor grow experience with a specific cannabis strain is the only way to know for sure. Administration of full doses of cannabis nutrients, ie heavy fertilization, as well as timely amounts of flowering boosters, can do wonders for yields, but this is only the case if you have a strain with a proven relationship to a serious fertilization schedule. Instead, you can try following a feeding schedule to dose nutrients in just the right amount.

Anyone who has ever tried juicing marijuana using boosters and potions can tell you that it is a waste of your time and money. Genetics will be the primary determinant of how strong you are and how much stash you take to harvest. Regardless of whether you do everything perfectly, you can, and most likely will, reach the point of being genetically stuck. Build up your feed slowly and steadily, monitoring your plant’s behavior at each step. Like it or not, there are no shortcuts to this one.

Identifying the problems with the NPK ratio of cannabis

If you grow a lot, you’re bound to run into some nutritional complications at some point. Early detection is crucial to fix problems and guarantee a good yield. A point for novice growers is that while it can be tempting to give your plants lots of fertilizer thinking they will grow more, this may be the first cause of problems for new growers.

bottom line

Less is more when it comes to feeding your cannabis plants; less is more. As you have read, problems related to under-feeding are easily dealt with and pose little risk to the health of your plant unless it has been completely deprived for a long time. On the other hand, overfeeding creates a lot of harder problems to solve and is more likely to harm your plants.

Start slow and low and also learn to study your plants to determine what they might need. By doing this, not only can you give them everything they need, but you will also become a more experienced grower and growing your cannabis will be a lot more enjoyable.

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