Top 10 Indoor Growing Problems with Cannabis

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Top 10 Indoor Growing Problems and How to Spot Them thumbnail

10 problems most indoor growers have, or will, encounter

Hi there and welcome (back) to Free the Tree!
Today we decided to group together the 10 Most Common indoor growing errors and how avoid them 🙂

1. Lack of Ventilation

Air circulation is vital to your plants, whether this is to intake more fresh air and CO² or to let out the compounds produced.
It’s important to at least have an exhaust fan and an opening in the tent from which fresh air can come in.

Signs of Lack of Ventilation

Leaves are stifled and unable to function causing slow growth and poor consumption of water and nutrients.
If you have signs of a nutrient deficiency but you know that your plant has enough nutrients available, this might be your issue.

How to solve ventilation problems

Here the name of the game is going to be fresh air! Here’s a couple tips:

Open the window of the room every day. This will replenish the air in the room.
Keep bottom sections of the grow room open. This will allow an air to be replenish
Add fans at the bottom of the grow room
Prune leaves that are too close to one another

2. Lack of Light

If the light source is too far from the Apex of the plant or its intensity isn’t strong enough the plant won’t be able to photosynthesis enough to function.
Instead of going through her normal stages she will focus on reaching for the light source until reaching a sufficient distance to photosynthesis enough for her development.

Signs of Lack of Light

Stretching plant, long weak stems, Nutrients are used poorly, photosynthesis is slow resulting in slowed growth, stems stretch and growth is scrawny.

How to Solve Lack of Light issues

In this case you really only have 2 solutions, you either need to get the light source closer to the plants or increase its intensity.

3. Humidity

High humidity causes the plants to use less water and more nutrients. Growth is slowed since the stomata are not able to open and increase the transpiration of the plant.

On the other hand, low humidity stress the plants because they need too much water.

Signs of humidity issues

Stretching plant, long weak stems, Nutrients are used poorly, photosynthesis is slow resulting in slowed growth, stems stretch and growth is scrawny.

Tips on Humidity levels in a grow room

Our suggestion in this case is to start with high levels of humidity and gradually lowering them and then leveling out around 50%

Read more about the importance of humidity levels

Humidity and Cannabis – What Humidity Level in the Grow Room

4. Temperatures

Whether it’s low or high temperatures the growth of the plant will be slowed.
Furthermore, large fluctuation in temperatures will increase the problem since the plant has to use energy in order to adapt its organism.

Signs of Temperature problems

Apart from the extreme cases where the plant burns near the light source the main sign will be slowed development (growth or flower development).
With high temperatures you’ll also notice that you need to water your plant much more often since they need more water to cool down.

Tips on Temperature levels in a grow room

You’ll want your grow room to stay between 19°C and 25°C and keep the temperature difference within an 8 to 10°C (15 to 20°F) range.

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5. Foliar Spray Damages

Spraying a solution into the foliage of your plant in order to speed up the intake of the different nutrients is a good idea, but must be done carefully. You can severely damage the foliage if you’re not careful.

Signs of Foliage damage due to Spray Applications

Generally the damage will look like the leaf is burnt where the final solution drops are located. You can also see round white rings on the leaves.

This can be due to the fact that watering on the leaves increased the intensity of the light source, creating a light burn problem; or that the nutrient mix was too concentrated thus damaging the foliage.

Tips to spray solutions on Marijuana Leaves

In order to spray your solution mix directly onto the foliage (leaves/stem/flowers) of the plant here’s a couple guidelines to follow:

Don’t use highly concentrated solutions
Don’t use solutions that are too acidic
Spray 15 minutes before your lights power off; This will remove the risk of having light burn.

Learn more about foliar feeding

Foliar Feeding – Tips to get the most out of your Spray

6. Over-watering

Over watering si definitely one of the most commonly seen issues when starting to grow your own plant, and the worst thing is that the symptoms are very similar to under-watering.

The main issue here is that the soggy soil cuts the air from the roots which retard the nutrient intake. With less nutrients the plants defenses weaken.
In severe cases root rot will start to appear which can lead to the death of the plant

We covered this in our guide on watering your marijuana plants for more

7. Under-watering

The opposite of over-watering but a little less common since generally when we start we’re taking careful care of our babies.

In this case when the soil is too dry the transportation of nutrient is severely slowed which can quickly create nutrient deficiencies, sick foliage and when exposed for too long, the roots to die

This is also covered in our our guide on watering your marijuana.

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8. Light Burn

Light burn is caused when the light source is too close to the Apex of the plants, saturating the leaves and burning the chlorophyll away.

Signs of Light Burn

We covered this in depth in our light burn article but basically you’ll see the most exposed leaves start to turn yellow/white and then die out

How to solve light burn?

Basically here what you need to do is raise the light source in order to have more distance between it and the Apex of your cola’s.
If you can’t do so due to a lack of room, you can try a plant training technique such as Super Cropping or in the most severe cases topping

9. “Hot Soil”

This referrers to soil that contains too much nutrients thus “burning” the plant.
The problem with this is that the plant can’t regulate the nutrient levels, in their natural process there’s an exchange in nutrients within the soil depending on the needs, with hot soil the plant cannot regulate

Signs of Hot Soil

You’ll notice signs of Nutrient Burn appearing. Basically the leaves will be turning brown, starting at the tips.

This should be treated quickly since it can spread fast and a large amount of foliage can be lost.

How to solve Hot Soil (aka nutrient burn)?

The best solution is to flush the soil, meaning to water it so much that the nutrients are flushed out.
Generally, you need to add at least 2 times more water than soil mass.
For example, you have a 3L pot of soil you’ll need to irrigate it with al least 6L of ph’ed water to flush them out

In case you’re thinking “I’ll just water them with no nutrients next time” this will make things worst!
If you simply water the medium the nutrients will be released, increasing the amount available for the roots to intake.

Another tip: Go for non-enriched or lightly enriched soils, it’s best to start low and add nutrients when needed than to go high and have to flush out the soil

Learn more about nutrient burn

Nutrient Burn – What is it? How to fix this problem

10. Dry Soil Pockets

Water has a tendency to take the quickest route through obstacles. Meaning that when you water your plants if you do so quickly your watering mix will take a path through the medium and follow it, leaving dry soil pockets within your pot.

Signs of Regular Dry Soil Pockets

This one is a bit tricky to identify, but here’s a couple pointers:

When watering your watering solution starts seeping out of the bottom very quickly
You need to water very often (and it’s not a root bound issue)
The plant seems to have deficiencies but everything else (pH, nutrient levels, Air flow, etc) is A-OK

How to solve Soil Issues?

The key here is to water the medium slowly and evenly, using a mister or a drip solution.
This slower irrigation system will make the water seep slowly through the medium, which will irrigate a much wider area of soil.

On our end we set up an drip irrigation system because watering with a mister just takes sooooo long.
It’s really something easy to set up, simplifies watering, saves time and is better for the plant, an awesome deal!
If you want to make your own, we grouped it all together in a DIY article over here

Alright folks that’s it for this one, don’t hesitate to send a message to let us know what you thought!
Until next time, be safe and grow easy

About the author

plant-lover

Plant Lover is Free the Tree's founder and a passionate grower of plants. Mostly from the city, I work on my computer all day so about 4 years ago, on my off time, I started growing to have some more green in my life. I never imagined I would fall in love with botany and discover so much about this plant. Since then I keep learning everyday, meeting new awesome people of our community and which keeps me growing constantly You can always get in touch with me on our Instagram!