Cultivating potent, nutrient-rich cannabis plants is no easy feat. But our simple guide will help.
Understanding how to avoid cannabis deficiencies is challenging. There's a lot to consider, and making critical mistakes is easy. We know it because we've been there before ourselves.
With that in mind, our team assembled this simple guide to help you avoid cannabis plant deficiencies.
So, keep reading to learn essential details regarding cannabis cultivation nutrients. Your plants will thank you (they'll thank us, too–you're welcome).
What's the difference between organic and synthetic cannabis fertilizers?
Organic cannabis fertilizer feeds soil microorganisms, while synthetic fertilizers feed the plant directly.
The Downsides of Organic Nutrients
- The slow release of cannabis nutrients may cause nutrient deficiency.
- Organic nutrients can attract pests.
- Organic nutrients are more expensive to use than synthetic fertilizers.
- The fluctuating nutrient content inherent to organic nutrients can cause deficiencies.
- Organic nutrients are more difficult to apply.
The Upsides of Synthetic Nutrients
- Synthetic nutrients give you more dosage control.
- Synthetic nutrients are convenient.
- Synthetic nutrients are more affordable to use compared to organic nutrients.
- Cannabis nutrient deficiency is easier to correct with synthetic nutrients.
Cannabis Nutrient Basics
What nutrients does a cannabis plant need?
The best cannabis fertilizers contain Nitrogen (N), phosphorus (P), and potassium (K). Here's how you know when your plant needs each one:
- Cannabis nitrogen deficiency: leaves look pale, turn yellow, curl and drop off.
- Cannabis phosphorus deficiency: older leaves experience dark spotting, and growth slows.
- Cannabis potassium deficiency: tips of leaves turn dark and look burnt.
What are cannabis macronutrients?
Cannabis macronutrients are valuable materials in your cannabis nutrient blend, like iron, zinc, magnesium, calcium, etc.
What is NPK Ratio?
NPK Ratio is the percentage by volume of nitrogen (N), phosphorus (P), and potassium (K) your cannabis nutrient blend contains.
What are secondary nutrients?
Essential secondary nutrients include calcium (Ca), sulfur (S), and magnesium (Mg). These nutrients are often unavailable to cannabis without proper pH level maintenance. Therefore, secondary essential nutrients are critical to adequate cannabis plant development.
Here's how to know when your cannabis plants need secondary nutrients:
- Calcium: growth is stunted, leaves have dead spots with dark green around them
- Magnesium: veins and outer edges take on a light green or yellow-ish hue
- Sulfur: leaves begin to yellow at the midsection before becoming completely yellow
What are cannabis micronutrients?
Cannabis plants need them in smaller quantities, but micronutrients play an essential role in their physiology. Micronutrient deficiency is somewhat rare, but without them, it's challenging to realize healthy yields and potent plants.
Here's how to know when your plants need cannabis micronutrients:
- Boron: spotting on new leaves and abnormal or thick growth at tips
- Chlorine: leaves yellowing, wilting, and stubby roots
- Copper: leaves are shiny or have dark blue or purple undertones
- Iron: new shoots and leaves appear yellow
- Manganese: yellow leaves quickly turning brown
- Molybdenum: leaves turn orange, red, or pink around the edges
- Zinc: fresh leaves don't open up; buds are loose and fragile
Cannabis Grow Types and Nutrients
What cannabis nutrients do hydroponic grows use?
Regardless of the cultivation method, cannabis plants need several essential nutrients to thrive. In hydroponic cultivation, those include:
- Nitrogen
- Phosphorus
- Potassium
- Calcium
- Magnesium
- Sulfur
- Trace Micronutrients and Elements
- Amino Acids and Vitamins
What cannabis nutrients are used for soil grows?
- Nitrogen
- Phosphorus
- Potassium
- Calcium
- Magnesium
What cannabis nutrients are used for indoor grows?
- Nitrogen
- Phosphorus
- Potassium
- Calcium
- Magnesium
What cannabis nutrients are used for outdoor grows?
While it varies based on your soil, here are the best nutrients for outdoor grows:
- Nitrogen
- Phosphorus
- Potassium
- Calcium
- Iron
- Zinc
- Magnesium
- Copper
- Manganese
- Cobalt
Cannabis Nutrients for Grow and Feed Stages
What are the best nutrients for cannabis seedlings?
Here are the best nutrients for cannabis seedlings:
- Nitrogen
- Phosphorus
- Potassium
- Calcium
- Magnesium
- Sulfur
What are the best nutrients for vegging cannabis plants?
The cannabis vegetative stage lasts between four and twelve weeks. Cannabis plants require significant light and nutrients during this period.
The best nutrients for the veg stage are the same essential nutrients for any cannabis plant. Still, their NPK ratio will vary as follows:
- High nitrogen
- Moderate potassium
- Low phosphorus
*You should consult a nutrient feeding schedule for specifics.
What are the best nutrients for flowering cannabis plants?
When selecting a fertilizer for flowering, here are the nutrients to look for:
- Nitrogen
- Phosphorus
- Potassium
- Magnesium
- Sulfur
*You should consult a nutrients feeding schedule for specifics.
Cannabis Nutrient Deficiency FAQs
Here are the common issues you may experience if you don't use a proper feeding schedule and an associated kit:
What is pH imbalance?
pH imbalance indicates the soil's acid-base composition is out of the ideal range.
What is nutrient burn?
Cannabis nutrient burn describes the stress plants are exposed to when they've been given more nutrients than needed in a given growth phase.
What is nutrient lockout?
When plants have the incorrect pH balance, water chemistry, light level, temperature, or nutrients, they won't properly absorb nutrients.
What is nutrient overfeeding?
Overfeeding marijuana nutrients occurs when the roots absorb excess nutrients, preventing water from being transferred through the rest of the plant.
What is nutrient deficiency?
Cannabis nutrient deficiency occurs when plants don't have the essential nutrients required for optimal growth.
Preparing and Using Cannabis Nutrients
Now you know the nutrients your cannabis plant needs to avoid cannabis nutrient deficiencies, here's how to use them:
So how do you prepare cannabis nutrients?
- Select the appropriate nutrients based on your cannabis feed chart
- Prepare lukewarm (ideally distilled) water for mixing and add nutrients.
- Measure electrical conductivity (see below) and adjust
- Measure and adjust pH levels
- Ensure your water is still lukewarm, and apply to the roots
When do you stop giving cannabis nutrients?
We recommend you stop feeding between days 63 and 70 of your plant's growth cycle.
How do you measure nutrients in the soil?
- PPM, or parts per million, can be measured using a TDS (total dissolved solids) meter.
- EC or electrical conductivity can be measured using an EC reader.
Why flush your cannabis plants?
The last step before harvest, flushing, allows plants to absorb any nutrients left in the soil by removing nutrient buildup at the roots.
The Best Cannabis Nutrient Brands
Ask any expert—Success Nutrients is the best brand for achieving cannabis growth success.
Our comprehensive feeding guide eliminates the need for bookmarking a cannabis deficiency chart. And our years of cultivation experience mean we've created essential growth blends that avoid nitrogen deficiency and other common nutritional pitfalls. Our kits include everything you need and nothing you don't.
Common Questions from Success Nutrients Customers:
Here are some common questions our customers ask:
What nutrients do commercial growers use?
To replicate the commercial growth experience, stock up on our complete kit to get the nutrients you need, including macro and micronutrients.
Should I use nutrients every time I water my cannabis plants?
No. We recommend regularly flushing with unenhanced water to maximize success; consult our feed chart for dates.
How long should I wait to feed nutrients after I transplant cannabis?
Wait about a month after planting, or until your plants have grown 3-4 sets of true leaves before giving them their first nutrient feed.
What are the best nutrients for flowering in soil?
Our Flowers blend has all the nutrients you need to flower successfully in soil, including nitrogen, phosphorus, potassium, magnesium, and sulfur.
How long to wait after flushing can you harvest?
Flush your plants approximately two weeks before you plan to harvest them.
What does silica do for plants?
Silica improves heat and drought stress, increases insect and fungi resistance, and creates robust and rigid cell walls.
How often should I give my plants nutrients in coco coir?
At the beginning of growth, plants need feeding every one to two days, with feeding intervals increasing to as much as multiple times per day when flowering.
When should I stop using nitrogen during flowering?
We recommend giving your plants nitrogen via our Flowers blend at regularly scheduled intervals until day 55 of your grow cycle.