Phosphorus Deficiency in Cannabis
by Joe Powers
This article discusses a specific nutrient—phosphorus—and its importance in growing healthy, high-yielding cannabis plants.
· What is phosphorus deficiency and why is it important to plant health?
· How to identify it
· How to prevent it
· How to fix it if you already have it
What is phosphorus and why is it important to plant health?
Plants use phosphorus to perform complex energy transformations. It aids the cannabis plant in cellular respiration (breathing), photosynthesis (converting light into food), healthy root development, increased disease resistance and thicker, stronger stems.
Consequently, a lack of necessary phosphorus can affect the health and growth of the whole plant. Left untreated, phosphorus deficiency may result in a small plants, low yield, low quality or even death of the plant (if severe enough).
How to identify phosphorus deficiency
Phosphorus deficiency can present itself in a handful of ways. Older leaves, toward the bottom, will start to darken to a deeper shade of green and plant growth will be drastically reduced. These older leaves will then begin to curl and develop a brown hue.
Next you may notice a “yellowing” of the leaves with dark green spots that start to spread. The whole plant may begin to look as if is starting to die, as it turns brown. The stem of the plant may turn red or purple. (This is not a symptom if the strain being grown normally has a purple or red stem.) Leaves may thicken. Buds are smaller, develop slowly and may even have a delay in normal development.
Phosphorus deficiency is a progressive issue and, if caught early, it is easy to fix and reverse.
How to prevent phosphorus deficiency
The best way to prevent the problem from taking root is to understand the fundamentals of growing healthy plants from the beginning. If the basics are taken care of and properly monitored throughout the duration of plant growth, only small adjustments will have to be made along the way to avoid a damaging deficiency.
Start with good soil and proper soil microbes. Having healthy soil that is rich in necessary ingredients, set to create life, is the proper way to begin. In nature, plants tend to grow in a very lively “ecosystem,” swarming with all sorts of life—microbes, among other things. The most effective way to prevent phosphorous deficiency in cannabis is to use the processes found in nature.
A highly recommended product, which has a 100% satisfaction rating in the cannabis community, is a product called Mammoth P. Mammoth P works by “mimicking” nature in an indoor (artificial) environment. It adds beneficial bacteria to the soil and unlocks the micronutrients—helping stimulate and maximize growth.
Mammoth P claims to increase bud yield by 16% and increase the stem strength by 6%.
Whether you are operating a small grow or a large industrialized operation, every increase in quality and strength matters.
How to fix phosphorus deficiency
Make sure the fundamentals are in proper working order, i.e., good soil with plenty of microbes, proper feeding of nutrients and watering.
Step One: Test and, if needed, adjust pH to the correct range.
The ideal range for phosphorus absorption by cannabis is 6.2–7.0 for soil and 5.5–6.2 for hydroponic. Test the pH nearest to the roots for the highest level of accuracy.
Step Two: Keep the temperature between 60°F and 88°F.
Even within this ideal range, a consistent temperature throughout the day is best. Large temperature fluctuations are not good because they add stress to the plants and prevent healthy growth and phosphorus absorption.
To check this, get a digital thermometer that keeps track of both the lowest and the highest temperatures throughout a 24-hour window.
Step Three: Introduce the right nutrients, at the right times, in the right amounts.
Once the pH and temperature are in the appropriate range, start slowly adding fertilizer that is high in phosphorus. A wide range of phosphorus-containing fertilizers are on the market, which can be added to and dissolved in water. One example is Agricultural Organics’ PHAT Bloom. (Each fertilizer used to treat phosphorus deficiency requires a different, specific mixture ratio, so consult the directions before using any of them.)
A more “pure” organic option, bat guano, can easily be found at Home Depot, Amazon or many other stores.
Another useful product is Marijuana Booster. Not only does this booster tend to a phosphorus deficiency, it also helps prevent other nutritional deficiencies by restoring the plant's natural nutrient balance.
Keep in mind while adding nutrients that the only thing worse than a deficiency in a specific nutrient is an abundance of nutrients, thus causing your plant to receive what’s called a “nutrient burn.” Nutrient burns are harder to recover from than deficiencies and, in most cases, the plants will not recover. Less is always more when introducing nutrients.
Before beginning, remember: It’s always better to prevent the problem before the problem occurs