Phosphorus Deficiency in Cannabis: Treatment Guide

Phosphorus (P), along with potassium (K), and nitrogen (N), is among the three main plant substances. Cannabis needs Phosphorus during its growth stages, through the vegetation stage and even better during flowering. Phosphorus deficiency cannabis occurs when the plant doesn’t acquire the needed amount for healthy and robust growth.

Phosphorus helps at the start of your plant’s life cycle through the growth stage and is also beneficial during the plant’s reproductive period. It is tremendously significant for most of the plant’s life. The cannabis plant will deteriorate if there is no phosphorus.

What is Phosphorus Deficiency Cannabis?

As its name implies, phosphorus deficiency cannabis is a symptom that the plant roots cannot get Phosphorus or is not sufficiently available.

This case happens either when there are low pH levels or a lack of Phosphorus in the plant.

What Are The Symptoms Of A Phosphorus Deficiency?

Here are the signs that may show on the cannabis with phosphorus deficiency:

Leaf Symptoms

  • Dried leaves are falling off.
  • Twisting and bending of leaves
  • Drying and burning of leaf tips
  • Blotchy or mosaic-spotted leaves

Leaf Color

  • Yellowing leaves where the specks did not appear
  • Clotting and spot creation (purple, bronze or brown) on bottom leaves
  • Darkening (gray, blue, or dark green) of the bottom, older leaves

Plant Symptoms

  • Reduced growth
  • Root rot
  • Twisted or small new growths
  • Stem discoloration (purple or red) starting at the base
  • Abnormal growth
  • Buds not thickening properly
  • In fertilized females: seeds aren’t fully developed
  • Other problems: root disease, mold, and more likely pests

*during the flowering stage: leaves closest to buds and below lights are afflicted the most firmly, creating purple or red spots with the encircling pale or flesh yellow. Leaves beneath may maintain their natural green color.

Phosphorus: A Mobile Plant Food

Phosphorus, like potassium, magnesium, and nitrogen, is associated with the class of mobile plant food. This nutrition is called mobile as when inside plants, they can be carried to parts where the weed needs it most. Since cannabis takes this nutrition from aging, leaves will exhibit the first symptoms of phosphorus deficiency cannabis. As the deficiency advances, the signs will then go up in the plant.

Cannabis requires Phosphorus in all of its growing stages, but specifically essential for bud production throughout the flower. It also has a big part in photosynthesis and overall growth.

Cannabis strains have unique nutrient requirements. This is similar to Phosphorus. It means that throughout the growing period, much as you use the equal amount of nutrition for all plants, specific strains may display phosphorus deficiency cannabis symptoms while some may be unaffected.

Phosphorus Deficiency Cannabis Despite Feeding

All commercially possible marijuana nutrients, particularly those made for flowering, contain more Phosphorus. You feed your cannabis plants based on the recommended dose for your nutrient and happen to detect the symptoms of phosphorus deficiency cannabis, and it is somewhat rare that nutrition is the source of it.

If so, it is instead an issue with the water pH level, nutrition solution, and growing mechanism. If the pH level is deficient, the cannabis plant is incapable of absorbing Phosphorus, although it is now.

How to Treat Phosphorus Deficiency Cannabis

PH Levels Problems Can Be At its Root

Growing issues with cannabis because of nutrient deficiency can occur even if it is well-fed.

Most often, an improper pH level is a primary source for a phosphorus deficiency cannabis. The reason is that cannabis prospers effectively in a moderately stable pH to absorb nutrition. For the Phosphorus, the perfect pH at your plant’s root is 6.2-7.0 when you cultivate in soil, and it is 5.5-6.2 when using hydroponics.

Hence, the first thing to do if you think phosphorus deficiency cannabis is to monitor and adjust the pH level at the root of the plants.

Drench Your Cannabis Plants to Reinstate a Healthy Roots

An improper pH at the root parts of cannabis often results in the accumulation of salts and minerals in the soil. To eliminate the richness of salts and reinstate substantial root parts and the right pH level, you must drench your cannabis. 

Drenching means flushing your plants with only massive amounts of pure, pH-ed water. The idea is to “water out” these buildup salts. After you drenched the plants, nourish them with the right amount of nutrients at the right pH level. 

If you are using hydroponics to grow your cannabis, you drench your hydro system properly and may want to make a new nutrition fluid for your pool.

Watering Properly

Improper watering of plants, mainly overwatering, can trigger a phosphorus deficiency cannabis. Water your cannabis correctly. Instead of watering it frequently, and in little amounts, it is ideal for watering it less frequently, though drenching the container’s entire soil. Always let the soil dry off between watering, too.

Lifting the container to assess its weight is a perfect way to inspect if the soil content is dry. It is better when the plant begins to wilt because of dryness than drowned with water. For the former, your parched plants can instantly recover. In the second, consistent soaking can result in severely growing issues.

Check Temperatures

The plant’s ability to absorb Phosphorus depends on the temperature. If the temperature drops below 15 degrees Celsius, phosphorus deficiency cannabis is perhaps to occur. Thus, be sure your plants are maturing at the right temperature. 

Adding Phosphorus during a Deficiency

After you omitted other causes of phosphorus deficiency cannabis, like improper pH level, cold temperatures, and overwatering, you can add Phosphorus.

Commercial pot mixtures that are pre-mulch, frequently have enough phosphorus amounts. Most of the premixed cannabis nutrition will include the right amounts, specifically maturing substances. Liquid, minerals maturing nutrients with easy to achieve Phosphorus offer a fast and quick way to add Phosphorus to your plants.

These plants absorption generous phosphorus amounts when they cultivate, meaning that it is somewhat hard to deliver them excessively. Since cannabis plants use ample nutrients, it is unbelievable that phosphorus deficiency cannabis would show before some other nutrient absences.

However, other cases where the cannabis may need very high phosphorus amounts, like when you cultivate under highly potent lights or when the cannabis is maturing in straight sunlight. In that event, you progressively increase your blossoming nutrient to deliver the plants with phosphorus amounts it requires.

Can You Add Excessive Phosphorus?

When it comes to cannabis, it is tough to add excess amounts of Phosphorus over other nutrients. Adding too much, on the other hand, is not healthy either. While the chances are slim, correctly, if you are using premixed cannabis nutrients, excessive Phosphorus will appear in other growing challenges and nutrient shortages.

After you deal with phosphorus deficiency cannabis, your plants must recover in several days. Like other deficits where mobile nutrition is concerned, the plant cannot “repair” the already discolored or crushed dried leaves in the bottom, though it will display successful shape in new growth at the top.

Avoid Deficiencies in Cannabis Plants

Some symptoms listed above won’t even wholly show up, even if the cannabis plant has severe phosphorus deficiency cannabis. For example, sometimes, the stalks aren’t tuning purple or red, which means that it is no problem until other signs show up. 

Occasionally, only several plants in the entire growing system will display phosphorus deficiency cannabis symptoms, while others around it are very healthy. This can occur even if a lot more cannabis plants are placed in the same system.

With the purple and red colors included with phosphorus deficiency cannabis, breeders purposely cause a short-term phosphorus deficiency cannabis to make the buds more vibrant. It is stunning to watch purples and red combined with green. It is achieved by reducing the temperature at a surprising level, hence blocking the plant’s ability to intake Phosphorus.

This does not work with every cannabis. Regardless of the variety, you are consuming, it will decelerate the overall development of cannabis and its buds. The leaves that are not green don’t efficiently complete photosynthesis, which is vital for the fast growth of some plants.

Starting with a cannabis variety that is already susceptible to purplish and reddish colors is the ideal way of producing buds with purple shade. Hence, you don’t have to do extra steps to make it purple. 

If you consider using cold temperatures, the least you do is wait until its ideal before the yield period. This will stop you from declining your final crop excessively.

You should keep in mind that the reddish and purplish color shown on the buds during this process does not show a more potent and more robust bud. Purple buds and green buds have the same strength. Although the leaves and buds might look attractive with reds and purples combined, you should also realize that this will delay the plant’s development and bud making. A red or purple leaf will not do more to add strength to your cannabis plant’s progressions.