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Magnesium: Top 5 Things You Need to Know

Magnesium deficiency corn

We humans look to magnesium to help calm us and lower our stress levels. These are two effects you’ll also feel knowing your crops have enough of this primary micronutrient. From the green appearance magnesium brings to your plants through chlorophyll, to the green dollar bills it brings to your wallet, here’s what you need to know about Mg.

1. Plants can only take up one form of magnesium

Mg2+ is the only form of magnesium that is able to be utilized by plants. If that’s not being picky enough, it also has to be dissolved in water. The majority of magnesium uptake occurs through mass flow. Products like BW-BioZinc 9%, a chelating agent that binds to metal ions, can help boost magnesium bioavailability and uptake.

2. Magnesium is a primary component of chlorophyll

The lush, green color we love to see in plants is a primary result of magnesium. Magnesium is the central core of chlorophyll, which is a catalyst for photosynthesis. The green pigment is then formed through the conversion of the sun’s energy into food for the plant. Because magnesium contributes to the green color of plants through chlorophyll, Mg deficiency can be seen in leaf color shifting from green to a more yellow tint, and in severe cases, a complete reversal from green to red.

3. Magnesium is mobile within plants

While it can be hard to get magnesium into plants, once it’s inside, it’s relatively mobile, unlike some other nutrients, like calcium. This means magnesium can move from older leaves to newer leaves, and deficiency can be seen on the older, outer edges of the plant as Mg moves to support the new growth.

4. Acidic soils have less magnesium

The more acidic your soil, the more likely your crops will experience magnesium deficiency. Generally, the eastern half of the United States has more acidic soils, with the Corn Belt having slightly acidic and southeastern states having highly acidic soils. Coarse soil also retains less magnesium, and leaching through the soil profile is common with excessive precipitation or irrigation. On the other hand, because magnesium must be dissolved in water to be absorbed by the plant, too little moisture can also cause deficiency.

5. Magnesium deficiency can cause grass tetany

If you have land for grazing livestock, you also need to pay attention to magnesium levels in your forages. When plants lack magnesium, the livestock that consume the forages are also not consuming enough magnesium. This can cause grass tetany, a highly fatal disease that primarily affects cattle, but can be found in all ruminant livestock. You can find more information on grass tetany here.

Magnesium can often be overlooked, especially if you live in an area with soil that is not predisposed to deficiency, but it’s an essential micronutrient worth paying attention to. Give us a call if your crops struggle to maintain healthy magnesium levels.