Cannabis Nutrients Deficiencies & Excesses

Marijuana

Having plant issues? Check out our identification charts later in this post.

Cannabis Nutrients 101

A question that I’m often asked and see many times on discussion forums is “how much bud can one plant produce.” There isn’t a simple answer to that question, in fact, it’s impossible to guess because of the number of variables that are at play. Some factors that can affect the final yield of your cannabis plants are soil quality, pH, amount and power of light, size of pots, strain planted and the nutrients that are provided and when.

Nutrients are broken up into three parts, primary nutrients, secondary nutrients and trace elements. All of the nutrients required by your plants come together to support healthy growth. The real secret to nutrients aren’t the ingredients but the timing of when they are added and what they are added with. If you can recreate the mixture of nutrients, water, and timing you can then grow one plant or a hundred plants, it will be the same.

It is critical that you view your plants each day for changes both positive and negative if something bad is going on you need to catch it early and deal with the issue immediately to avoid a reduction in your final bud yields. It is also crucial that when you water your plants with added nutrients that you check the run-off from your plants for pH levels. Remember keeping your plants as healthy as possible will increase the final yield and quality.

How Nitrogen, Phosphorous and Potassium Effect Cannabis Growth (cannabis nutrients)

(N) Nitrogen: Healthy foliage growth is spurred by Nitrogen which helps plants produce proteins that are used to be the building blocks of your plant’s foliage. Too much Nitrogen will cause your cannabis plants to experience rapid growth but poor flowering. Not enough Nitrogen will cause stunted growth.

(P) Phosphorous: Phosphorous is important to the root system of your cannabis plant and later on during growth it helps produce big fat healthy buds. Too much Phosphorous will cause your leaf’s to bleach (turn yellow) while not enough will cause your leaves to die off.

(K) Potassium: Potassium is crucial to have overall healthy plants and plant development. Too much Potassium will cause your plant to not be able to uptake Nitrogen and Phosphorous, not having enough will cause poor plant health.

There is no perfect measurement of the amount of nutrients your cannabis plants require for healthy growth. Each maker of nutrients has their own formula. Cannabis nutrients can be bad if you use too much. I’m a firm believer that less is more when it comes to fertilizing my plants. I would much rather under feed than over feed my plants. Over-feeding will kill your plants, cause low yields and even produce terrible tasting end product. Don’t let this scare you too much, just use fewer nutrients than your manufacturer lists on the packaging. I usually cut it in half. Never underestimate the ability of cannabis plants to adapt to bad conditions and still thrive. Remember you are growing a weed.

Remember, use a cautious hand with your cannabis plants. The better schedule you keep for your plants the better they will respond. The right amount of light, water, Co2, and nutrients are the ingredients of perfect cannabis.

What Nutrients We have Been Testing

I’ve been growing cannabis in soil for over 10 years and in that time, I’ve tried a lot of nutrients. I’ve made my own, mixed and matched as well as used nutrient systems. I’ve found that the nutrient systems are easy to use and work better overall for my plants.

Here are some products that I recommend to other cannabis growers.

Fox Farms Soil Nutrients

FoxFarm Soil Trio Big Bloom / Grow Big / Tiger Bloom

Product features

– Start with Grow Big for abundant green growth
– Switch to Tiger Bloom at the first sign of bud set or flowering
– Use Big Bloom throughout all growing cycles to heal root systems and increase nutrient cycling
– Ideal for mature, late-season flowers and fruit
– SIMPLE AND EASY TO USE! Great for beginners!

Dutch Nutrients

Dutchpro Starter Pack for Soil

Product description

– This great new starter pack by Dutch Pro really takes a headache out of choosing what to get for your first grow!
– This pack even includes a bottle of their famous Dutch Pro Explode
– 1 x Dutch Pro Original Grow Soil
– 1 x Dutch Pro Original Bloom Soil
– 1 x Dutch Pro Explode
– 1 x Dutch Pro Multi Total
– 1 x Dutch Pro Take Root

advanced nutrients

Advanced Nutrients Bloom, Micro & Grow

Product description

– Advanced Nutrients ph perfect grow
– No competitor offers this full spectrum of quality ingredients
– balance-free pH perfect technology works around the clock to calibrate and adjust the pH for you

 

 

general organics

General Hydroponics General Organics Go Box

Product description

– Bio Thrive Grow
– Grow and Bloom fertilizers
– GO liquid supplement
– Premium biological plant foods and supplements

 

 

Images By Jorge Cervantes

Excess

  • Stems Become Weak
  • Foliage Becomes Weak
  • “Greeness” moves up
  • Bottom Leaves Turn Lush Dark Green
  • Water/Fluid Transport System Becomes Weak
  • Harvest Tastes Green
Nitrogen Nutrients

Deficiency

  • Plants Are Shorter with Smaller Leaves
  • Leaves Lose Luster
  • Yellowing Progresses Upward
  • Lower Leaves Turn Yellow
  • Leaves Continue to Yellow, Curl and Discolor
  • Leaves Start to Drop
  • Premature Flowering and Low Yield

Excess

  • Minor Leaf Wilt
  • Growth May be Stunted
  • Uptake of Potassium, iron, magnesium, and manganese blocked
Calcium Nutrients

Deficiency

  • Stunted, Plant, Diminished Harvest Flower Development is Slow Yellowish-Brown Irregular Spots Develop on Leaves and Margins Lower Leaves Contort and Curl
  • Root Tips May Die Back

Excess

  • Leaf Tips Yellow Before Appearing Burned
  • Leaves Yellow and Drop
 Boron Nutrients

Deficiency

  • Stem, Tip and Roots Grow Abnormally Growth Shoots Appear Burned and May Contort Necrotic Spots Develop Between Leaf Veins Leaves Thicken and Become Brittle
  • Rust Colored Corky Stems Develop
  • Root Tips Often Swell, discolor and Stop Elongating

Excess

  • Yellowish-Bronze Leaves are Smaller and Slower to Develop
  • Young Leave Develop Burned Tips and Margins
  • Note” Both Severe Deficiency and Excess of Chlorine Have the Same Symptoms: Bronze-Colored Leaves
Chlorine Nutrients

Deficiency

  • Leaf Tips and Margins Burn, Turn Bronze ColorYoung Foliage Turns Pale Green and WiltsRoots Develop Thick Tips and Become Stunted

Excess

  • Interveinal iron Chloroisis
  • Few Branches Grow
  • Roots Start to Decay or Become Thick and Slow Growing
Copper Nutrients

Deficiency

  • Young Leaves and Shoots Wilt, Contort and May Die BackLeaf Tips and Margins Turn Dark-Green to Copper-Gray and Die BackGrowth is Slow and Yield Decreases

Excess

  • New Leaves Grow Thin Blades
  • Newer Leaves Develop Interveinal Chlorisis
  • Leaf Tips and Margins Burn
  • Less Internodal Space
  • Diminished Harvest
  • Zinc and Iron Micro-Nutrient Deficiencies
  • Calcium and Magnesium Deficiencies Appear
  • Lower Leaves Curl, Develop Spots
  • Roots Tips Die Back 
 Phosphorous Nutrients

Deficiency

  • Vertical and Lateral Growth SlowsWeak Plant Susceptible to Diseases and PestsPetioles Turn Purplish ColorLeaves Turn Bluish Green
  • Dark Copper-Colored or Purple-to-Blackish Dead Blotches on Lower Leaves
  • Severely Affected Leaves Develop Dark Brownish Metallic purple Colored Leaves Continue To Curl, Contort, Wither and drop
  • Weak Plant Susceptible to Disease and Pests

Excess

  • Stunted Growth
  • Dark Green Foliage
  • Symptoms Appear as an Overall Salt Toxicity
Magnesium Nutrients

Deficiency

  • Overall Sickly Appearance Deficiencies Exist 4-6 Weeks Before Outward Signs are Apparent Interveinal Yellowing and Irregular Rest-Brown Spots Appear on Older and Middle-Aged Leaves Older Leaves Dry, Often Curl and Drop

Excess

  • Young and Newer Growth Develops Chlorotic, Dark Orange to Dark-Rusty-Brown
  • Mottling on the Leaves
  • Tissue Damage Shows on Young Leaves Before Progressing to Older Leaves
 Manganese Nutrients

Deficiency

  • Young Leaves Show Interveinal Chlorosis Symptoms First Necrotic Spots Develop on Severely Affected Leaves, Which become Pale and Fall Off Telltale Sign of Manganese Deficiency is Where Margins Remain Dark Green Surrounding Interveinal Chlorosis Symptoms Spread from Younger to Older Leaves as the Deficiency Progresses

Excess

  • Causes a Deficiency of Iron
  • Leaves Discolor
 Molybdenum Nutrients

Deficiency

  • Leaves DropIn Cold Weather Older and Middle Leaves Yellow with Possible Interveinal ChlorosisLeaves Become Distorted Margins dry leaves Drop

Excess

  • Interveinal iron Chlorosis
Iron Nutrients

Deficiency

  • Young Leaves and Shoots Wilt, Contort and May Die Back

Excess

  • New Leaves Grow Thin Blades
  • Newer Leaves Develop Interveinal Chlorosis
  • Leaf Tips and Margins Burn
  • Less Internodal Space
  • Causes Calcium, Magnesium, Zinc and Iron Deficiencies
  • Root Zone is Acidified
  • Root Tips Die Back
Potassium Nutrients

Deficiency

  • Older Leaves Turn Pale and Suffer Chlorosis Leaf Margins, Tips Turn Rusty Color and Burn Stem Branching May Increase Flowering Retarded and Diminished
  • Stems Often Become Weak, Scrawny, and Sometimes Brittle

Excess

  • Overall Smaller Plant Development and Uniformly Smaller, Dark-Green Foliage
  • Leaf Tips and Margins Could Discolor and Burn When Excess is Severe
 Sulfur Nutrients

 Deficiency

  • Bud Formation is Slow and WeakYoung Leaves Turn Lime-Green to Yellowish, and Growth is StuntedAs Shortage Progresses, Leaf Veins Yellow and Lack SucclenceLeaf Tips can Burn, Darken, and Hook Downward
  • Long Purple Steaks Might Appear the Length of the Stem When Combined with an Overall Nutrient Deficiency
  • Stems Often Turn Woody

Excess

  • Zinc Overload is Very Rare But Extremely Toxic. Severely Toxic Plants Die Quickly
  • Excess Zinc Interferes with Iron’s Ability to Function Properly and Causes an Iron Deficiency
Zinc Nutrients

Deficiency

  • New and Young Leaves Exhibit Interveinal Chlorosis, Develop Small, Thin Blades that Contort and Wrinkle often Stem Tips Fail to Elongate and Growing Shoots/Tips Become Bunched Up.
  • The Leaf Tips, and Later the Margins, Discolor and BurnReduces Internode Spacing, Stunts New Growth, Including Buds, and Can Severely Diminish Yield

Avoid Nutrient Problems With:

  • Air Circulation
  • Air Ventilation
  • Air Temperature
  • Air Humidity
  • Adequate Light
  • Clean Water
  • Organic Soil
  • Regular Maintenance
 
  • Immobile Nutrients Show Nutrient Deficiency & Excess on Newer Leaves
  • Mobile Nutrients Show Deficiency & Excess on Older Leaves
  • Toxic Salt Buildup Locks out Nutrients Causing Deficiencies & Excesses
  • Over-watering is Common. Causes Nutrient Deficiencies & Excess.

Conclusion

The best way to prevent issues with your cannabis plants is to keep a close watch and to use nutrients carefully. Introduce nutrients slowly at low strength and build up the concentration over time. Feeding issues with appear rather quickly if there are nutrient issues.

Always keep a close watch on your plants daily. You should be examining the leaves and stems very closely to make sure they are healthy. Keep your grow area and tools clean and make sure that your plants have good ventilation. If you keep on top of these things your grow will be successful.

Marijuana Grows Indoors 101: How to grow cannabis indoors using LED grow lights
When to Harvest your Cannabis Plants
5 Tips When Buying LED grow Lights
Top 5 Beginner Strains For New Growers
Cannabis Nutrients Deficiencies & Excesses

Leave a Reply