Why Do Plants Need Magnesium? Are Your Plants Getting Enough Of It?

Sometimes you could do everything to make your garden flourish. Start with good soil at the perfect sunny spot, water, prune, and mulch, and you can still find your plants unhappy. There could be several reasons behind those yellow, wilting leaves and lack of fruiting. A common problem is a nutrient deficiency.

The deficiency could come from several different nutrients essential for plant growth, an important one of which is magnesium. Magnesium is necessary for photosynthesis. This means that magnesium levels will affect the plant’s ability to make food. Look for the symptoms and cater to the deficiency before it turns into anything serious.

Why Do Plants Need Magnesium?

The availability of magnesium is paramount to plants since it’s responsible for the development of chlorophyll. Without chlorophyll, there won’t be any photosynthesis. Without photosynthesis, the plants won’t be able to survive.

In the gardening world, nitrogen, phosphorous, and potassium are called primary nutrients. Magnesium, sulfur, and calcium are secondary nutrients. At the same time, there are certain micronutrients as well that the plants need in small quantities, but we won’t talk about them right now. Now is magnesium’s time to shine!

Magnesium may be a secondary nutrient, but that has nothing to do with its importance to the plants. Magnesium is just as essential as any of the primary nutrients. The term “secondary” only signifies that the plants need magnesium in smaller quantities than the primary nutrients.

In short, magnesium is a vital element to ensure your plant’s health. Whatever you may be growing in your garden, you need to maintain adequate magnesium levels in the soil to ensure that the crop flourishes.

If enough magnesium isn’t available, fertilize it to improve the soil quality. Once the soil has ample magnesium, you can avoid several disorders and diseases that might affect the plants.

What Are The Signs Of Magnesium Deficiency?

Look for the signs and detect the deficiency in its early stages. Getting to the source of the problem sooner means the fix is going to be simpler. Letting the problem persist may turn it into something long-lasting. Here’s what you should be looking for to decide if your plants are experiencing magnesium deficiencies:

1. Interveinal Chlorosis

This is one of the earliest signs of magnesium deficiency. The leaves’ prominent veins will keep the natural dark green color around them, but the rest of the leaf turns yellow. This yellowing between the veins will appear in the older leaves initially, spreading, eventually, to the younger ones too.

2. Necrosis

Necrosis is one of the later symptoms of the deficiency. Yellowing between the veins, in chlorosis, will ultimately lead to the entire leaf turning yellow, wilting, and dying.

3. Pigmentation

Sometimes, red-brown or rust-colored tints appear on the leaves, typically near the leaf’s tip and margins. They’ll gradually turn bigger and spread throughout the plant.

4. Early Leaf Fall

The symptoms are often also accompanied by the early falling of the leaves. The plant may start losing its leaves in late summer.

5. Reduced Flowering And Fruiting

With low magnesium levels in the soil, your plants’ ability to produce new leaves, fruits, and flowers will be severely hampered.

What’s The Diagnosis?

The symptoms of magnesium deficiency can sometimes be confused with other problems, especially if you’re new to gardening. Potassium deficiency, for example, also results in chlorosis. The only difference is that the pattern is more regular and restricted to the interveinal and marginal zones in magnesium deficiency. It can also be confused with zinc, or chloride deficiencies, and certain viruses.

So how can you tell for sure if magnesium levels are low in your garden? A soil test will tell you which nutrients your soil lacks. Performing the soil test in time and amending the ground for the desirable levels of different nutrients will prevent any deficiency symptoms from appearing in the first place.

You can either order a professional soil test or buy a soil testing kit and perform it independently. All plants have their specific requirements. So, compare the test results with the plant requirements to see if you need any amends in the soil.

Always Perform A Soil Test Before Doing Anything
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How To Fix A Magnesium Deficiency In Soil?

The outcomes of the soil test will tell you if the soil needs more magnesium. If the magnesium levels are low, you can do some things to restore the desired level.

The two most commonly used sources for magnesium are Epsom salt and lime. If the soil’s pH is ideal and you need to raise the magnesium levels, go for Epsom salts.

Lime is the one to pick if you also want to raise the soil pH while adding more magnesium. It all depends on the soil test, what it shows, and the need of the specific plants you grow.

Steps To Follow If You Want To Add Magnesium To The Soil

  1. Till the top 6 to 8 inches (about 15 to 20 cm) of the soil using a manual tiller or a hand shovel.
  2. Apply the magnesium source to the ground by using the package’s instructions. They’ll either be applied in granular form or as a liquid solution, and the recommended dosage will also be mentioned with the instructions.
  3. Till the soil again after application to mix everything uniformly in the ground.

You can also use a water-soluble magnesium source to make amendments to an existing crop. Foliar spray of a diluted solution of Epsom spray can quickly relieve the symptoms on the leaves. About a 1-cup of Epsom salt in a gallon (about 3,8 liters) of water is ideal for the foliar solution. Spray it weekly, but remember that the foliar application is only a temporary fix. The symptoms will reappear unless you amend the soil.

Warning: Do not apply magnesium to the soil without performing a soil test. When you do apply magnesium, only use enough to correct the deficiency. Applying more than what’s necessary isn’t just a waste of resources but can also lead to other problems. You’ll learn about magnesium toxicity later in the post.

Organic Remedies

You don’t necessarily have to use chemicals to give magnesium to your plants. Organic sources are just as beneficial. They will offer a long-term solution to magnesium deficiencies in your existing and future crops.

Apply rich, organic compost regularly to the land. The best thing about amending with compost is that it adds magnesium to the soil and improves its ability to keep moisture. But it also prevents the nutrients from being washed away after heavy rainfall.

Composted turkey, cow manure, horse manure, and poultry manure are excellent organic sources of magnesium.

Which Plants Are Susceptible To Magnesium Deficiencies?

Some plants demand more magnesium than others. You’ll need to be particularly careful of the magnesium levels for grapes, tomatoes, peppers, eggplant, watermelon, squash, cucumbers, raspberries, apples, roses, and rhododendrons. Magnesium deficiencies are also common in brassicas, particularly cabbages, greens, and broccoli.

In comparison, you won’t usually have to worry about magnesium levels if you’ve planted beans, peas, sweet potatoes, lettuce, beets, or Swiss chards. Unless magnesium is critically low in the soil, these varieties won’t complain.

If you’re fond of growing edibles, head to our post – How to Grow Herbs Indoors? It will tell you the most important things you’ll need to know about herb gardening.

Is Magnesium Toxicity Possible?

Magnesium is essential for plants, but only in the required quantities. Yes, magnesium toxicity is also a thing! It’s rare but, quite certainly, possible.

High levels of magnesium will not directly affect the plant. Still, they will inhibit its ability to absorb other essential nutrients. The absorption of calcium and potassium will significantly suffer if the soil’s magnesium levels are too high. What’s more, an excess amount of magnesium may result in deficiency symptoms of other nutrients in plants.

For a quick fix, you should go for amending the soil with the nutrients in lower concentrations. Doing so will relieve the deficiency symptoms that you see in your plants. But, for a long-term solution, you’ll need to dig deeper into the source of the excess magnesium and cater to the problem.

Final Words

So now you know why plants need magnesium? Have your plants been looking miserable lately? If yes, they might suffer from a magnesium deficiency. Even if they’re not, make sure your garden is rich in nutrients. When it has every element in its right concentration, the soil will turn every seed it touches into a beautiful, healthy plant. You’ll have plenty of fruits and vegetables to fill your pantry. Isn’t that the ultimate goal of every gardener?

Don’t let your green thumb let you down with the simplest gardening mistakes. Pay attention to your plants’ behaviors. They’re usually quick in expressing their dislikes. Check for yellowing of the leaves, spotting, and early falling. All the symptoms mentioned earlier suggest a magnesium deficiency. Respond promptly and address the problem before it takes a severe turn.

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