Mulching also makes it easier to find bugs that could spoil your plant. Flip the mulch in the morning and check beneath. If there are bugs in your grow, you’ll find them under the mulch.
Besides, the roots don’t grow as deep as they should, affecting the plant’s nutrient supply. If the roots survive air pruning, they will harden like the stems and might even turn green. I could be wrong, but I don’t think roots with green backs still function as roots.
You must replace the soil that’s swept away when you water to keep the roots farther from the surface.
perlites, rocks, or anything that breaks up the compact medium will help your roots breathe below the medium.
Cover The Exposed Roots With Medium
Cannabis roots growing above the soil is mainly caused by a lack of oxygen in the grow medium. The roots need to breathe, and so they reach for the air above the grow medium. Other than oxygen deprivation, the following factors can lead to roots growing above the soil.
Soil mediums can be compact, blocking all air from reaching the roots. You should consider adding vermiculite to break up the soil and allow the exchange of air between the environment and the roots.
However, for outdoor marijuana plants, the roots can run into water pipes or rocks. These hard surfaces are impenetrable; thus, the roots will grow upwards.
If The Roots Run Into A Solid Obstruction
Tip: Whatever you decide to do, ensure you aerate the grow medium. Protruding roots is the plant’s outcry for help. By aerating the medium, you’re attending to the entire plant— not just the affected roots!
When the plant gets rootbound, it tries to find more space to grow, forcing the roots to grow upwards.
Sometimes leaves will tend to cup or curl down due to root problems, like the plant above, but sometimes the curl upwards too, like the poor plant below (this was caused by poor drainage and plant was overwatered, leading to a pretty severe case of root problems):
Another plant from that same batch which reacted differently
Step 3: (Optional) Provide your plant with a beneficial bacteria like Hydroguard to help roots recover quickly (more info about root supplements below). Hydroguard will help fight root rot by creating a colony of good organisms to outcompete the root rot.