How Does Boron Affect Marijuana Plants?

Boron deficiency is rare for marijuana plants, and occurs almost exclusively in western soils when it does happen. It is primarily indicated by the browning or graying of growing tips and then their subsequent death. The lateral shoots will begin to grow after that, but then they will eventually die as well. These shoots will look sunburned, gnarled, and will have a bright green coloration. Brown necrotic dead spots will show up on the leaves, and the area around them will be composed of dying tissue. These deficiencies are similar to a lack of Calcium, but Boron deficiencies are unique in that the necrotic spots they produce are smaller.

Petioles (leaf stems) and the main stems of the marijuana plant will be brittle and potentially hollow. Boron deficiency targets exclusively newer growth, meaning that it is “immobile.”

Eventually, the roots will stop growing and the secondary roots will also shorten and become swollen. Fungal and bacterial attacks are more common as the roots become more vulnerable.

Overabundant Boron is started largely by over-fertilization. Leaf tips will turn yellow and start curling inward. Eventually, the leaves will fall off and the marijuana plant will die. Download my free marijuana grow bible for more tips about nutrients and marijuana plants.