Cal Mag Deficiency During Flowering And Supplementing It

Cal-Mag Deficiency During Flowering And How To Supplement

If you start to notice cal-mag deficiency during flowering you’ll need to act fast to save your plant’s bloom. During flowering, plants need more magnesium and calcium because of bud production. This is a key productive stage in a plant’s life that requires lots of nutrients to sustain the bloom stage. Calcium and Magnesium are two of the most important secondary nutrients. They are a little less important than the primary nutrients – N, P, K).

The Impact Of Cal-Mag On Plants

These two minerals through secondary are vital to the biological processes in a plant. Let’s see what each mineral does.

Calcium Benefits to Plants Magnesium Benefits to Plants
Gives cell wall more rigidity Assists in enzyme production
Allows plants to have a strong structure and shape Helps plants make chlorophyll
Makes cell walls healthy Helps plants grow into  full maturity
Helps the healthy cell wall to regulate the proper transfer of other nutrients Assists in the absorption and transport of essential nutrients like phosphorous and iron.
It is vital for cell division and formation in plants  
Activates specific enzymes in plants  
Helps transport the organic molecules in plants  
Highly essential for the development of healthy fruit structure  

Signs Of Cal-Mag Deficiency During Flowering

It is not easy to detect Cal-Mag deficiency in the early stages of a plant. Thus, it is important to act as soon as you detect the first sign. First signs appear in the lower leaves of the plant. The tips of the leaves curl upwards and turn brown. The brown spots increase in size and number starting from the lower to the top part of the plant. The youngest leaves on the top part of the plant also get brown spots with discoloration of veins.

Botanicare HGC732110 Cal-Mag Plus

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How To Supplement Cal-Mag Deficiency During Flowering

Water is one of the essential requirements for all plants. Did you know water is one of the supplements for these secondary nutrients – calcium and magnesium? Natural water contains abundant calcium and magnesium as dissolved minerals. Plants should be able to get these two nutrients in plenty from the soil/water itself. Tap water also contains these two secondary minerals. You don’t have to worry about using natural water only. Soft water has a low pH with minimal minerals in it.

If you live in an area with low pH, you will have to look for Cal-Mag supplements for your plants. Hard water contains high concentrations of calcium and magnesium. Using this water means you don’t need to add any Calcium or Magnesium supplements. Treated water requires Cal and Mag supplements addition. Because the distillation process removes the good minerals from the water.

How Much Calcium And Magnesium Should You Use?

You can make a homemade cal-mag supplement using Epsom salts (Magnesium sulfate) and Calcium nitrate. Mix 2 parts calcium to 1 part magnesium. You will need 6g Calcium Nitrate and 4.5g Epsom salts per gallon of water. In specific situations, you might need to adjust the nutrient levels to fit your type of deficiency. If you buy a pre-mixed cal-mag supplement, you will get the right recommended mixture. Stick to those levels for the best results. Remember, excess use of these supplements can be bad for your plants!


In most cases, these two supplements can be easily available in water and soil. But in exceptional cases, supplements are required. Cal-Mag supplements are available to buy. But you need to pay attention to the labels. Get something that consists of cal and mag only. Be sure to get a supplement that does not contain other nutrients. Supplements that contain nitrogen and other nutrients bring a risk of over-feeding. This is dangerous to your plants!