Input reduction is one of our four key values here on the farm, and one of the ways that we strive to follow that is by decreasing our reliance on plastics and other waste products. Instead, we utilize a method of plant propagation known as soil blocking, which essentially uses slightly compressed blocks of soil to grow seedlings in place of traditional plastic pots. The reasons for doing this are many, most notably that soil blocking creates a healthier plant (via “air pruning” of the roots) that is less prone to transplant shock, and it also helps to eliminate the sometimes single-use nature of plastic plant pots. It’s a win for the garden and the environment!
Ryan & Jillian Garrett, Owners of Blue Ridge Farm
Have you ever wondered why that big potted plant that you bought at the store never thrived in your garden? Were you curious as to why, when you finally dug up that dead plant, its roots were still in the original shape of the plastic pot?
The answer to these questions is that the poor plant was suffering from a condition known as “rootbound,” brought about by too much time spent having its roots constricted in a plant pot. Rootbound plants are a common occurrence, and one of the many reasons that we constantly remind customers that the size of a transplant doesn’t matter – it’s how healthy the roots are!
One of the many reasons that we turned to soil blocking as our method of plant propagation was because it is such a fantastic way of ensuring healthy plants. Soil blocking utilizes a process known as “air pruning,” which promotes a healthier root system than putting plants in a pot. In a soil block, air pruning occurs when the plant roots hit the outside air of the soil block edges and are effectively “burned” off, causing the plant to consistently produce new branching roots (thereby creating a very healthy root system).
In a traditional plastic pot, the plant roots are constricted and have nowhere to go, heading down to the bottom of the pot and swirling around indefinitely. This creates an unhealthy condition known as being “rootbound,” which can not only stunt a plant but also potentially kill it. After being put in the ground, a rootbound plant can continue to be stunted, unable to overcome its constricted root system, or take much longer to establish than a healthier air pruned plant. This is one of the many reasons we prefer to utilize soil blocking. The plants we offer for sale as well as the ones we grow on the farm are happier, healthier, and far more productive as a result!
Don't be fooled by vibrantly green, over-fertilized plants, as their accelerated growth comes at the cost of weaker leaves and stems. This weakness means they are more likely to break, and also means that the plants are more likely to suffer pest problems, as studies have shown that aphids and other insects are drawn to heavily fertilized plants.
Seedlings that are too young may be unable to withstand the shock of transplanting, but bigger isn't always better when it comes to transplants. A larger, more mature plant tends to be less able to withstand the the shock of transplanting because it has become rootbound in its plastic pot. Additionally, an older plant has switched over from root growth to leaf production, meaning it will be less able to acclimate after being planted in the garden, resulting in a slower harvest and therefore a lower overall yield.