smart pots problem

Smart Pots And Air Pots: What Are They And What’s The Difference?

Published : Feb 5, 2019
Categories : Cannabis cultivation

Air pruning the root zone of cannabis promotes outstanding health and rapid growth. Air Pots, Smart Pots, and Spring Pots do the job perfectly, but what are they exactly?


Smart Pots, Air Pots, Spring Pots, and the numerous variations on this theme all work in a similar manner. That is, they let air in through the side of the pot, which promotes air pruning of the apically dominant root tips. This in turn makes the root diverge in two different directions, and eventually, a dendritic pattern appears. When the perimeter roots are pruned by the air, their growth slows prior to the new shoots developing. In this time, the plant responds by increasing root growth everywhere else in the root ball.


Plants that have been grown in an air pruning pot not only have a complex outer root pattern, they also have larger and denser root balls in general. This equates to more surface area for gas exchange and water and nutrient uptake, while providing more stability for plants.


Another benefit of pots that encourage air pruning is that they prevent roots from winding around the sides of the pot and eventually strangling themselves in a knot. This can promote every cannabis farmer’s worst nightmare, Pythium or root rot. It can also subject the plants to unnecessary root stress from overheating. When roots hug the pot walls, they come into contact with a very hot surface. Especially on the sunward surfaces.


Plastic pots tend to heat up considerably, transferring the heat to the grow medium. When a grow medium heats up too much, plants can display many symptoms of stress in the growth patterns and leaves. These include over and underfeeding simultaneously, cupping and canoeing of leaves, and many symptoms attributed to pathogens and bug infestations. Overheated grow media can have growers chasing their tails trying to sort out problems that don’t really exist.

Air pruning pots keep the growing medium at a manageable temperature. The permeable surfaces expose water to the air, encouraging evaporation. This in turn cools the pot walls, which then help keep the grow medium cooler. Combined with mulching, air pruning pots make plants more resilient to heat stress in general.


These types of pots also give the root zone access to plenty of air. Roots, not just leaves, need air as well to remain healthy. Not only do roots need to breathe; a robust oxygen exchange helps keep pathogens at bay. A friable and well-structured grow medium allows plenty of air to move about in the root zone. Air pruning pots allow plenty of air to not only trim roots, but to permeate the entire grow medium. Plants can draw in air from 360°, rather than only relying on air available at the surface. Traditional pots in comparison only have minimal ability to promote efficient air movement.


Air Pots are made from a perforated and uniquely profiled plastic sheet that is rolled into a cylinder to form a pot. A perforated base is held in place when the pot is rolled, and is located a few centimetres from the bottom. This lets water freely drain right through and encourages airflow around the bottom of the pot. The profiled surfaces train roots to grow towards perforated air holes where they are air-pruned. The air holes are also an escape zone for water, which evaporates and keeps the pots cool.

The nature of the pot means larger plants can be grown in smaller pots with less grow medium. This makes them more cost-efficient for the same results, and allows more plants per square metre of available space. There are a range of pot sizes, and the material from which they are made is available in custom-sized rolls. This way, large pots can be made in situ, of any capacity, and up to a metre deep.


Smart Pots are made from a dense fabric that has been used for decades for a number of other purposes in the horticultural industry. The fabric is sewn into pots with bottoms made from the same material.

They come in various sizes, from only a few litres right up to 4,000 litres. People are surprised to hear they have been around for over forty years, especially in the tree-growing industry. The fabric from which they are made allows 100% exposure to the air over the whole surface of the pot. Roots grow as they please and are air-pruned when they reach the air layer between the pot and the grow medium.


The Spring Pot addresses one issue associated with fabric pots—their lack of rigidity. The Spring Pot functions as any other fabric pot, only it has a built-in spring that encircles the pot, giving it a firmer structure. After the pot has been used, it can be collapsed so it takes up minimal storage space. They come in a variety of sizes and have sturdy handles for easy moving about.


When root zones from each type of pot are examined, it is easy to discern the differences and similarities in root growth. There is a definite geometric pattern to Air Pots. It is easy to see where the roots diverge, then diverge again after they have been air-pruned.

Smart Pots and other fabric pots have less of an organised appearance, and the roots are more randomly spaced and patterned. However, it is again easy to discern the divergences in the roots where they have been air-pruned.

One thing’s for sure; cannabis responds vibrantly to being grown in a way where there is plenty of air availability at the walls of the pot. Larger, thicker stalks and greater plant volume in general are quite obvious when grown side-by-side with traditional pots. The same rules apply indoors or outdoors. Give them a try. You will be stoked.#

Air Pots and Smart Pots are two favourite solutions for air pruning the roots of cannabis plants. Find out more at Zambeza Seeds.

A warning onusing smart pots

Active Member

Just wanted to pass this along to others that use smart pots, or are considering them.

I’ve been really happy with my smart pots and have been using them for a couple of years.

However, do not place them on the ground in an area where the ground retains moisture. I found out the hard way that this is not a good idea. The soil in the pots could not dry out, and would actually wick the moisture out of the ground underneath them and cause the soil to be too moist. This encouraged root rot in several of my plants and killed them. Not good at all.

Next year I will be using the same pots, in the same location, but I will be placing a layer or two of rocks and rubble underneath them to encourage proper drainage. I may even use some drain pipe ( the kind with holes in it, like for a septic leach field ) to help keep the excess water from building up under them.

Just thought I would pass this on so others don’t make the same boo boo as I did.

Well-Known Member
Well-Known Member

lmao. I put mine inside a another pot where it would be taller,Well the plant started looking funny so i took it out of the other pot and there was a 3ft tap root in the bottom where when i watered it did not drain.

Plants dont like wet feet,either.

Well-Known Member

dont place smart pots on top of wood and even plastic, ive noticed roots will attempt to grow into wood very easily and get root bound quick causing root growth to stop, yes i know smart pots air prune roots but i wouldnt advise putting them on anything but instead get a larger pot and place em on top of eachother and use something like supersoil or you can even layer your amendments like guanos on the 2nd pot with high in Potassium and phosphorous and have your plant timed to grow into that pot when flowering, very effective.

if you can create a small 1×1 pvc pipe frame and use a strong nylon string and do criss crosses across it you can have your smart pot sit on that (make it strong) itll be most effective for air pruning, i also have used chicken wire with no problems but i am skeptical that metal will be absorbed or flaked onto the roots and you have to worry about rust depending on where you live.

Active Member
Well-Known Member
Active Member

Good ideas folks. Mine are outdoors, so when it rained and the soil got soaked the moisture could not leach out or drain due to it sitting on wet ground for so long. Even after a week after the rains quit the ground under the smart pot was still soaking wet, as was the soil in the pot. If I had put a layer of rocks, or drainrock or something down under the pots that would have kept the bottom dry then my plants would have done all right. Anything to keep them up out of the wet earth but still give good support.

Anyway, that s the plan for next year anyway.

Just wanted to pass this along to others that use smart pots, or are considering them. I've been really happy with my smart pots and have been using them…