How to Diagnose and Treat Magnesium Deficiency in Cannabis Plants

In many plants around the world, magnesium is an absolutely essential element. It is the foundation element for chlorophyll, which in turn is needed for photosynthesis. This is no different for cannabis plants, which can very quickly die from magnesium deficiency if not acted upon correctly. Luckily, it is very simple to prevent and fix plants with this ailment. Simply read our guide below and you will never have to worry about magnesium deficiency in your grow again.

How to Diagnose Magnesium Deficiency

Magnesium is a mobile nutrient, meaning it can move around the cannabis plant. Often, it is transferred from the oldest leaves at the bottom of the plant to the newer leaves at the top. Therefore, it is likely that you will need to observe older, lower leaves to check for magnesium deficiency. The most obvious sign of this ailment is a yellow and/or bright green colouring that will run along the edges and veins of the leaves. The edges of the leaves may also very dry and crisp to touch.

How to Treat Magnesium Deficiency

The cause of magnesium deficiency is most likely a pH problem. Regardless of your grow medium, if the pH surrounding the roots of the plant is too low, magnesium is unable to make its way into the plant. Therefore, it is essential that your pH levels are consistently balanced. In a soil set-up, a pH level of around 7.0 is perfect to ensure magnesium absorption. In a hydroponic set-up, a pH level of around 6.0 will suffice. If you have restored the balance of your pH levels and your plant is showing signs of increased magnesium deficiency, it may be best to flush your grow with pH tested water and regular doses of magnesium filled, cannabis specific nutrients. Please note that any leaves which have been damaged considerably by magnesium deficiency are unlikely to improve, so focus on ensuring new leaves do not show signs of this ailment, rather than trying to recover older, affected leaves.