As mentioned above, don’t cut off your damaged leaves. These will be an excellent indicator of recovery. Unlike an iron deficiency, for example, leaves in a magnesium shortage won’t heal so commonly. You can cut them off when you’re sure the problem has been solved. It’s always better that if discoloration continues, this happens in the already damaged leaves. The last thing you want is to think you cured a nutrient shortage, only to see it reappear on new leaves.
Don’t cut the damaged leaves right away. These probably won’t go back to normal, but it’s a good way to see if the situation worsens. This way, they will die off before affecting the upper, newer leaves. Once you see the deficiency is gone, make sure to trim the unhealthy members.
Magnesium is best absorbed by the roots when the soil has a pH between 6.0-7.0. If you run a hydro-plantation, the recommended pH is slightly more acidic, within 6.0-6.5.
Make sure you have all the information you need to stop a magnesium deficiency in your cannabis plant. We show you how to prevent this occurrence and solve the issue if it happens to you.
Magnesium shortage happens most commonly in indoor grow rooms. So, if you start seeing yellow leaves on the plant in your closet, here is what to do.
If you’re very attentive on a daily basis, you may start to see that the plant stagnates its growth. This might take you a couple of weeks to recognise.
The most common visual symptom of this deficiency will definitely be the colour change in the leaves. Yellow or light green colouring will start to appear on the veins and edges of the bottom leaves. The deficiency will continue to move upwards until the whole plant is infected and it eventually dies. At the beginning, brown, rusty-looking spots will appear amongst the yellowness of the leaf. If left untreated, the leaf will eventually curl up at the edges as a sign of death. These will also feel very rough and unhealthy to the touch.
The problem might also be in the lack of essential nutrients in your soil or water. If the above method does not seem to show any progress, a supplement will be needed. Look for a calcium-magnesium one. Apply around 5ml of Botanicare Cal-Mag Plus to every 3.7 litres of water and you’ll hopefully see an improvement in approximately a week.
Published : Aug 23, 2017
Categories : Cannabis cultivation
Ever wondered what those yellow leaves were and how you could prevent them from killing your marijuana plant? Find out how to stop magnesium deficiency.
Coco coir is a great growing medium, but it can cause problems for growers concerning micronutrient uptake. Magnesium, along with calcium and iron, is one of the three micronutrients cannabis plants cropped in coco have difficulty absorbing.
However, the second is more difficult to detect. Growers that use lightly fertilised soil and liquid nutrients lacking in trace elements can unexpectedly get hit with a magnesium deficiency during mid-late bloom. As the marijuana plant matures, roots essentially drink up all the micronutrients in the medium. Without adequate supplementation, magnesium deficiency strikes.
Hydroponic growers that let the pH of the nutrient solution slip to 5.0 or below will likely experience magnesium deficiency. Water with too low a pH in the reservoir is a recipe for micronutrient lockout. Indoor soil growers often encounter magnesium deficiency for two reasons. The first is over-watering the soil. Roots in soggy soil just can’t access the nutes.
Magnesium deficiency is the definition of a bottom to top nutrient imbalance in cannabis. Growers will first notice unhealthy looking lower growth. It’s the oldest and lowest leaves that will signal the advance of a magnesium deficiency. In the beginning, bottom leaves will yellow and the tips will dry out into a crunchy brown.
As above, rinse out the substrate. But instead of adding a supplement, a better long term solution is to consider a nutrients upgrade. Specific nutrient lines customised to soil, coco or hydro grow styles make life a whole lot easier. Premier brand base-nutes are formulated with the complete macro and micronutrients needed for cannabis cultivation.
Probably the biggest mistake novice growers make is rushing to apply a quick fix by increasing nutrient doses. In fact, this will likely lead to nutrient lockout. No matter the growth stage or medium, yellow leaves and brown spots starting from the bottom are a red flag for magnesium deficiency. Micronutrient deficiencies always start in the root zone; magnesium deficiency is no exception. The problem must be remedied at the source. More on that a little later.
Unfortunately, magnesium deficiency is mobile, so it will spread up the plant if left unchecked. As the deficiency spreads to the shoots, they will turn purple and leaf chlorosis will accelerate. Grower reaction time, as always, will be the defining factor. Don’t mistake magnesium deficiency for nitrogen starvation.
Magnesium deficiency too frequently stunts marijuana growth. Be it early in vegetative growth or late into the bloom cycle, this is one deficiency no grower wants. With our practical advice, magnesium deficiency can be avoided and overcome.
Soil growers should consider potting up from smaller containers filled with lightly fertilised soil to large containers with a time-released fertiliser/soil mix. After a few weeks of vegetative growth, roots will be hungry for nutes and more fertile soil will save you money on bottles of liquid alternatives.
Micronutrient deficiencies are avoidable and in the worst case scenario, very treatable. Magnesium deficiency is a common problem. Here’s how to solve it.