Smokin Moose
Fallen Cannabis Warrior & Ex Moderator
Phosphorous - (P) (mobile in plant, immobile in soil)
Phosphorous deficiency in cannabis will show up in older growth first, with the leaf tips possibly curling downwards. When phosphorus is deficient, slow and spindly reduced growth will be noticed. Leaf damage is usually patches that are a dull, dark green to bluish green, in severe cases older leaves and petioles turning reddish purple caused by accumulations of anthocyanin. Younger leaves may be yellowish green with purplish veins when nitrogen is also deficient, and darker green veins when phosphorus is deficient. Necrotic (dead areas) spots occur on the leaves' margins in the advanced stages. Leaf tips can look burned as well. Phosphorus deficiency is most common when pH is above 7 or below 5.5. Phosphorus will bind with soil very easily. Excess phosphorus could cause micro nutrient deficiencies in zinc and iron. Cannabis uses phosphorus for photosynthesis, respiration, storing carbohydrates, cell division, it is also involved in energy transportation (ATP, ADP), nucleic acids, enzymes and phospholipids that are important for membrane structure. Phosphorus helps build strong roots, is vital for seed and flower production. Highest levels of phosphorus are used during germination, seedling growth and flowering. However, that does not mean that cannabis is a phosphorus hog. It is not. It consumes more potassium and nitrogen and magnesium than phosphorus. It will use more phosphorus in flowering than in its vegetative (growth) stage. Also, excess phosphorus can cause a decrease in uptake of zinc, iron and copper, which will start a chain reaction of other macro and micro nutrient deficiencies. Cold temperatures of 55 degrees Fahrenheit or 12 degrees Celsius will have a negative effect on phosphorus uptake.
Severe phosphorus (P) deficiency during flowering. Fan leaves are dark green or red/purple, and may turn yellow. Leaves may curl under, go brown and die. Small-formed buds are another main symptom.
Phosphorus deficiencies exhibit slow growing, weak and stunted plants with dark green or purple pigmentation in older leaves and stems.
Some deficiency during flowering is normal, but too much shouldn't be tolerated. Red petioles and stems are a normal, genetic characteristic for many varieties, plus it can also be a co-symptom of N, K, and Mg-deficiencies, so red stems are not a foolproof sign of P-deficiency. Too much P can lead to iron deficiency.
Purpling: accumulation of anthocyanin pigments; causes an overall dark green color with a purple, red, or blue tint, and is the common sign of phosphate deficiency. Some plant species and varieties respond to phosphate deficiency by yellowing instead of purpling. Purpling is natural to some healthy ornamentals.
Phosphorous deficiency in cannabis will show up in older growth first, with the leaf tips possibly curling downwards. When phosphorus is deficient, slow and spindly reduced growth will be noticed. Leaf damage is usually patches that are a dull, dark green to bluish green, in severe cases older leaves and petioles turning reddish purple caused by accumulations of anthocyanin. Younger leaves may be yellowish green with purplish veins when nitrogen is also deficient, and darker green veins when phosphorus is deficient. Necrotic (dead areas) spots occur on the leaves' margins in the advanced stages. Leaf tips can look burned as well. Phosphorus deficiency is most common when pH is above 7 or below 5.5. Phosphorus will bind with soil very easily. Excess phosphorus could cause micro nutrient deficiencies in zinc and iron. Cannabis uses phosphorus for photosynthesis, respiration, storing carbohydrates, cell division, it is also involved in energy transportation (ATP, ADP), nucleic acids, enzymes and phospholipids that are important for membrane structure. Phosphorus helps build strong roots, is vital for seed and flower production. Highest levels of phosphorus are used during germination, seedling growth and flowering. However, that does not mean that cannabis is a phosphorus hog. It is not. It consumes more potassium and nitrogen and magnesium than phosphorus. It will use more phosphorus in flowering than in its vegetative (growth) stage. Also, excess phosphorus can cause a decrease in uptake of zinc, iron and copper, which will start a chain reaction of other macro and micro nutrient deficiencies. Cold temperatures of 55 degrees Fahrenheit or 12 degrees Celsius will have a negative effect on phosphorus uptake.
Severe phosphorus (P) deficiency during flowering. Fan leaves are dark green or red/purple, and may turn yellow. Leaves may curl under, go brown and die. Small-formed buds are another main symptom.
Phosphorus deficiencies exhibit slow growing, weak and stunted plants with dark green or purple pigmentation in older leaves and stems.
Some deficiency during flowering is normal, but too much shouldn't be tolerated. Red petioles and stems are a normal, genetic characteristic for many varieties, plus it can also be a co-symptom of N, K, and Mg-deficiencies, so red stems are not a foolproof sign of P-deficiency. Too much P can lead to iron deficiency.
Purpling: accumulation of anthocyanin pigments; causes an overall dark green color with a purple, red, or blue tint, and is the common sign of phosphate deficiency. Some plant species and varieties respond to phosphate deficiency by yellowing instead of purpling. Purpling is natural to some healthy ornamentals.
