Cannabis Nutrient Excesses&Dificiencies | COOLER PANELS

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Cannabis Nutrient Excesses & Deficiencies

TOO LITTLE

Short bushy plants, small leaves
Leaves will look dull
Yellowing of leaves goes from outside into the center
Lower leaves yellow and die out
Will flower earlier (NOT A GOOD THINGS)
Leaves will curl and become brownish/yellowish

TOO MUCH

Stems will be soft/weak
Leaves soft and drooping
Dark Green color moving
from leave tips into center
Won’t drink water as quickly
When smoked, it tastes very grassy

N

Nitrogen

TOO LITTLE

Plant doesn’t grow as big
Leaf stem turns purplish
Leaves turn teal/bluish green
Bottom leaves copper/purple/black leaves
Curling, withering, dropped leaves

TOO MUCH

New leaf tips will be thin
Yellowish leaves, but green stems in the leaf
Leaf tips burn(crisp up die)
Less spacing between nodes (shorter plant)
Less flower production
Zn, Fe, Ca, Mg problems show up
Lower leaves curl and have spotting
Flower tastes like chemicals
Root tips start to die show less and not long

P

Phosphorous

TOO LITTLE

Older leaves turn pale/yellowing
Leaf tips turn brown and look burned/crispy
Stem branches grow longer
Less flowers and bad/empty flowers grow
Stems become weak, thin, and sometimes brittle

TOO MUCH

New leaves thin
Less spacing between nodes (shorter plant)
Leaf tips burn(crisp up die)
Zn, Fe, Ca, Mg problems show up
Lower leaves curl and have spotting
Flower tastes like chemicals
Root tips start to die show less and not long
Root PH very acidic PH ↓
Root tips die, show less and not long

K

Potassium

TOO LITTLE

Unhealthy plant, less flowers produced/smaller flowers
Flower development slower
Yellowish-browning spots on leaves
Lower leaves curl and twist

TOO MUCH

Leaves excessive wilting
Plant doesn’t grow a lot
Problems absorbing nutrients

Ca

Calcium

TOO LITTLE

Plant looks unhealthy/sick
Plant looks fine for 4-6 weeks before problem shows
Old leaves dry/curl fall off
Leaf veins yellow and brown on older leaves

TOO MUCH

Shorter plant/slower growth
Dark green leaves

Mg

Magnesium

TOO LITTLE

Bud formation is slow and weak
Young leaves turn yellowish, growth is slow/short
Leaf tips burn/get dark/leaves hook downward
Purple streaks appear on stems
•Stems turn woody/fibrous

TOO MUCH

Small plant, dark green leaves
Leaf tips discolored.
Potential burning when too much is added

S

Sulfur

TOO LITTLE

Stem and roots grow abnormally
New Stems appear burned and twisted
Black dead/mold-looking spots appear on leaves Leaves thicken and become brittle
Rust-colored stem

TOO MUCH

Stems will be soft/weak
Leaves soft and drooping
Dark Green color moving
from leave tips into center
Won’t drink water as quickly
When smoked, it tastes very grassy

B

Boron

TOO LITTLE

Leave's tips burn and turn bronze colored
New leaves are pale green and wilted
Roots stop growing

TOO MUCH

Yellowish bronze leaves, smaller and grow slowly
Young leaves grow with burned tips

Cl

Chlorine

TOO LITTLE

Young leaves yellow in the center
Black dead/mold-looking spots appear and leaves fall off.
Some parts of the plant will be dark green, while others are yellowing and spotting.
Spreads from younger leaves to older leaves.

TOO MUCH

Young, newer leaves have a dark orange rust coloring on leaves
This will appear on younger leaves before older ones.

Mn

Manganeses

TOO LITTLE

Leaves drop
In cold weather, the middle leaves become yellow
Leaves become twisted and dry

TOO MUCH

Leaves discolored (all sorts of colors)
Causes lack of iron

Mb

Molybdenum

TOO LITTLE

New leaves yellow and leaf tip becomes thin and twist
Stem won’t grow and causes plant to be more bush-like
Leaves look burned and discolored
Reduces spacing between stems and flowering, which lowers the amount of production

TOO MUCH

Plant dies very quickly
Causes plants do not intake iron

Zn

Zinc

TOO LITTLE

Young leaves wilt and could die before growing
Leaf tips turn dark green to copper gray and die back
Growth slows and yield is less

TOO MUCH

Slower growth
Leaf veins start yellowing
Less branches
Roots start dying and become thick

Cu

Copper

TOO LITTLE

Growth is slowed and yield is less
New leaves start to yellow from inside out (stem to tip)
Stem branches grow longer
As it continues, larger leaves start to yellow
Leaves may drop, and black dead moldy spots can develop

TOO MUCH

Leaves turn bronze with dark brown spots
Phosphorus becomes too little, check lower leaves

Fe

Iron

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