Last week we talked about soil health and ways to improve it through organic matter, no-till gardening methods, and compost tea. After putting all of this effort into creating high quality soil, the next step is to make sure that the containers used for planting are going to promote healthy plant growth. Container growing, or growing in pots instead of in the ground, is often the choice for greenhouse growers considering space can be limited and mobility is crucial. The two pots on the market that seem to provide the greatest benefits for plant growth are fabric and Air-Pots.
In a traditional pot the roots are forced to grow around the container in a constricted pattern. The roots may spiral, twist, kink or become strangled which results in reduced uptake of water and nutrients. To battle this issue, both fabric and Air-Pots incorporate the process of air-pruning in their designs. Air-pruning happens naturally when roots are exposed to air in the absence of high humidity. This causes the tips of the roots to become dehydrated stopping their growth, causing the plant to constantly produce new and healthy branching roots. This is beneficial for the plant because it creates a strong fibrous root system allowing the plants to absorb more water and nutrients for faster growth.
Below are two videos; one explaining the benefits of a fabric pot vs traditional pot and the second explaining the benefits of an Air-Pot:
Fabric Pots vs. Traditional Pots:
A fabric pot (Smart Pot in the video) does not have any visual drainage holes, however, the fabric is highly porous. This allows for increased aeration and for the roots to grow through the pot. As the roots grow through the pot they will air-prune achieving that desired root growth mentioned above. In addition, the increased oxygen is healthy for the roots and quickly dries the fabric pot. In this environment roots will stay cooler avoiding heat build up which would otherwise create thermal stress for the plant. They don’t freeze they don’t crack and the man in the video states that he has used his fabric pots for 6 to 7 years and they are still going strong. They are also difficult to over-water and plants can be planted into the the walls and the floors of the pot.
Air-Pots vs. Traditional Pots
The Air-Pot has visual holes all around the sides and bottom preventing all root bound or root circling. Just as the fabric pots the Air-Pot employs air-pruning as its greatest benefit. The shape of the inside wall guides every root towards an air hole where air-pruning stimulates root branching. This rapidly creates those massive outward pointing fibrous roots. These pots also provide high airflow.
Since both the fabric and air pots follow similar designs that eliminate root circulation and promote air-pruning, it is hard to make a pros/cons list between the two. From researching into a handful of online forums it seems that the grow community agree that both pots perform substantially better compared to the other types of pots on the market. Some differences between the two is that fabric pots can require watering more often since they dry out faster than Air-Pots. Air-Pots can leak water out of the sides creating a mess during watering and some growers mention pests creating nests in the root hole areas on their Air-Pots.
Overall, both pots perform better than traditional pots since a breathable container for maximum aeration and air-pruning are ingredients for a strong stocky root system. The type of grow containers used in your greenhouse can be just as important as using healthy soil. Fabric and Air-Pots are the containers that can help you accomplish optimal root development, but when it comes to choosing which pot is best between the two, the one factor that would sway my decision is their huge difference in cost. Fabric pots go for around $5 ea where Air-Pots can cost around $25 ea.
Do you have any experience with this topic? What pots do you use? Please leave your thoughts in the comment section below.