Top 7 Cannabis Growing Mistakes Leading To Nutrient Problems

Nutrient Problems

November 14th, 2020   |   Updated on January 5th, 2022

Whether you use cannabis for medical reasons or just like to smoke up every once in a while for the fun of it, there are a lot of benefits to growing your own weed plants from home.

Not only will you save money a lot of money in the long run, but you’ll have complete control over the strains you grow.

On top of that, growing at home gives you the chance to start a fun new hobby that you may never have known you enjoyed. Just try to realize that there’s some hard work involved and there’s always the risk of making some mistakes along the way.

Some of the most common growing mistakes can lead to minor issues, but some can cause big problems, especially when it comes to how the plants uptake and react to nutrients.

Here are the top 7 cannabis growing mistakes that can lead to nutrient problems for the entire crop.

Starting With Poor Genes

It doesn’t matter if you’re starting your next cannabis crop from seeds or from clones, the reality is, it’s all about good genes.

If you start with seeds or clones that have weak genetics, chances are they won’t react as well to nutrients. It’s just basic science that high-quality genes produce high-quality plants.

Even if you’re trying to save money, never try to save the budget when it comes to genetics. You’re better off saving a few bucks on the fertilizers than on your seeds, so whatever you do, avoid buying from cheap seed banks or using those free samples that came along with the last batch of seeds you purchased.

Whether you’re buying Sensi seeds, White widow, or a cross of strains such as Zamnesia’s Runtz seeds, you need to get them from trusted sellers, that you know for sure offer high-quality seeds.

So what does plant genetic makeup have to do with nutrients? It’s actually very simple. When you start with poor genes and discount seeds or clones, you usually won’t have enough information to make smart decisions about nutrients.


Try to think of your plants of your children. Just like infants, young cannabis plants need a healthy dose of nutrients, vitamins, and minerals to grow big and strong. Without the right nourishment, your babies (plants) won’t be able to thrive, and they might not even survive.

From the very beginning, it’s up to you as the parent (grower) to deliver those nutrients and make sure they’re getting a healthy amount of each nutrient they need. By not doing that, you’ll put your plants at risk.


Underfeeding is a common mistake, but an even more common (and bigger) mistake is overfeeding. Many growers, especially new ones, assume that there’s no limit to how many nutrients the crop gets, but this couldn’t be further from the truth.

Plants don’t have a digestive system like humans, so when you overfeed them, they aren’t able to expel all that excess food and water.

Instead, the excess nutrients – the salts in particular – eventually build up in the roots and soil and block the uptake of any more nutrients in the future.

By overfeeding your plants, you could actually cause them more harm than by underfeeding them. To prevent overfeeding, SFGate gives a good explanation on how to check if you’re administering too much fertilizer:

“A straightforward way to tell if a plant suffers from over-fertilizing is by checking its foliage, flowers and fruit.

A lack of blooms or fruit can indicate that the soil is receiving too much nitrogen, which encourages foliage development instead of healthy flowering and fruiting.”

Poor pH Monitoring & Adjustment

The pH scale plays an enormous role in how a crop handles nutrients. This scale determines how alkaline or how acidic a solution is, and just like all things, cannabis plants can only survive and thrive within a specific pH range.

The pH for a crop is measured through the soil, and it should range between 6 and 7. You can check the pH by monitoring the soil runoff.

Just water your plants as you normally would with the usual amount of nutrients, then raise up one of the plant buckets, place a container beneath it, and gather up some of the water that runs through the bottom of the plant pot.

Then, you’ll test this runoff with a pH measuring tool, and if it is within the 6 to 7 range, you’re good to go.

If not, you’ll need to make some adjustments to the pH levels of the water you use for feeding. This can be done with pH adjusting products, like pH Up and pH Down.

So What Does pH Have To Do With Nutrients?

Everything, actually. Soil pH has a huge effect on the growth and development of plants because it determines whether a crop will be able to absorb the nutrients from the soil.

This is why advanced growers check pH every single day to make sure things remain on track.

Lack Of Research on The Water Source

Plants are fed nutrients through water, so it’s obvious that you’ll want to pay close attention to the water source you’re using.

Not only should you pay attention to the pH of the water, but you also need to research on the minerals, bacteria, and contaminants within it.

For example, if a grower lives in a home that uses a hard water source, it would not be wise to use water straight from the tap for watering the crop.

The high levels of calcium and other minerals in hard water can build up in plant root systems, causing issues later on when it comes to nutrient uptake.

Using The Wrong Size Containers

Even if you’re using the best cannabis fertilizer and delivering the perfect doses with each watering, you’ll run into problems if you fail to use the correct container size.

When the container is too small, the roots don’t have room to stretch, and eventually, they’ll become root-bound.

To prevent root-binding from happening, just make sure to transition the plants to larger pots before the roots start winding themselves along the pot edges.

Up-potting might seem like a big chore, but you’ll run into some major problems if you keep your plants in the same size containers for too long.

Using The Wrong Soil

The soil itself contains nutrients that plants need to grow, so unless you’re growing hydroponically, selecting the right soil is a big step in any grow op.

Make sure the soil you use is light and airy, free from contaminants, and offers good drainage so that the water can flow through and deliver nutrients to the entire root system.