Magnesium Deficiency in Plants
Magnesium is vital for photosynthesis and developing chlorophyll pigments. If plants are lacking magnesium, either of these cannot occur.
Magnesium Deficiency Symptoms in Plants
Magnesium is an immobile nutrient; symptoms will show in newer growth first. Signs can include yellow spots that turn brown and dead leaves. The veins in old leaves will become yellow, known as interveinal chlorosis. The plant may show rust-colored spots. If magnesium deficiency is ignored, it can prevent the plant from producing.
How to Treat Cannabis Magnesium Deficiency
Check the pH levels and if they are not within range, flush your grow medium. Applying Epsom salt is a common quick fix for magnesium deficiency. Mix one teaspoon per liter and water your plants. If you haven’t, check your water mineral levels as it may have a high magnesium level. You can search a local water analysis that shows the level of trace minerals commonly in tap water but varies throughout the year.
How to Prevent Cannabis Magnesium Deficiency
Prevention is always better than waiting for a problem to occur before fixing it. Once magnesium deficiency is noticed, it could be too late. Plants can be deficient over a month before symptoms appear. Use a large container with high-quality compost. Powdered dolomite limestone can be added to help root absorption. Grow shops also offer Magnesium/Calcium rich feeds.