Last updated: March 11, 2022

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A Magnesium Fertilizer is a fertilizer that contains magnesium. It can be used to correct an existing imbalance of this element, or it can be applied as part of a regular fertilization program for healthy plants and lawns.

The best Magnesium Fertilizer in the UK: Our selection

Magnesium Fertilizer: Frequently asked questions

What types of Magnesium Fertilizer are there and what determines a good product?

There are three types of Magnesium Fertilizers. They include:

Magnesium Sulfate (Epsom Salt) – This is the most common type of magnesium fertilizer and can be purchased at any garden center or home improvement store. It comes in a variety of sizes, from small bags to large barrels that hold over 100 pounds. The smaller sized packages will cost you between $1-$3 per pound while larger quantities may run as high as $5-6 per pound. If you have access to water with a lot of minerals such as well water then this might not be necessary for your plants since they already contain some level of magnesium naturally occurring in the ground/water source used by your local municipality or utility company. However if you live on city water which has been treated using chemicals like chlorine, fluoride etc., it’s likely that there isn’t much natural mineral content left so adding something like Epsom salt would help restore those levels back up again and make them more available to plant roots through foliar feeding applications (spraying). Another reason why I use epsom salts is because my tap water contains very little calcium but plenty sodium chloride aka table salt…so when I spray

The best Magnesium fertilizer is one that contains the right amount of magnesium for your plants. It also needs to be in a form that will dissolve easily and quickly so it can get into the plant’s system. A good source should contain other nutrients as well, such as calcium, sulfur and boron which are all needed by cannabis plants.

Who should use a Magnesium Fertilizer?

Anyone who is concerned with the health of their plants or trees. Magnesium deficiency can cause a wide variety of problems, including yellowing leaves and stunted growth. It's also important to note that magnesium deficiencies are often accompanied by other nutrient imbalances (such as calcium), so it may be wise to use this product in conjunction with our Cal-Mag Fertilizer for optimal results.

Based on what criteria should you buy a Magnesium Fertilizer?

The best Magnesium Fertilizer is the one that meets your individual needs. Consider what you need it for, how much of a yield you want from each application and whether or not there are any specific elements in the fertilizer that might be beneficial to your plants. There’s no “best” product out there; only products that work well with certain types of soil and crops.

There are a few things to look out for when comparing the different types of Magnesium Fertilizers. The first thing is that you should compare the percentage of elemental magnesium in each product, as this will give you an idea about how concentrated it is and what kind of results can be expected from using it. Another important factor to consider is whether or not there are any additional ingredients added into the fertilizer which might help boost its effectiveness or make up for other deficiencies in your soil’s composition. Finally, if possible try and find out where exactly these products were manufactured so that you know they have been made under high quality conditions with strict regulations regarding their production process.

What are the advantages and disadvantages of a Magnesium Fertilizer?


Magnesium is the fourth most abundant mineral in our bodies. It plays a role in over 300 biochemical reactions and helps maintain normal nerve, muscle and heart function as well as healthy bones.


The only disadvantage of a Magnesium Fertilizer is that it does not contain any nitrogen. If you are using this fertilizer on your lawn, be sure to use another type of fertilizer with some nitrogen in it as well.

Shopping Guide: Everything you need to know

Which brands and manufacturers are represented in our review?

In our review, we present products from various manufacturers and suppliers. The list includes products from the following brands and manufacturers, among others:

  • Nortembio
  • Nortembio
  • Nortembio

What is the price range of the featured products?

The cheapest Magnesium Fertilizer in our review costs around 6 pounds and is ideal for customers who are conscious about their money. However, those who are willing to spend more money for better quality can also spend around 33 pounds for one of the more expensive products.