epsom salt for cannabis plants

Epsom Salts: a natural hack to grow healthy cannabis plants

Epsom salt is the best and most natural way of adding magnesium and sulfur to your cannabis plants. The benefits are astounding and there is little risk of overfeeding. Find out why you should use Epsom salt in your next grow.

Epsom salt is the nickname given to magnesium sulfate. The name comes from the spring water of Epsom, England. Farmers were quick to discover that Epsom water had “magical” healing properties, and its fame quickly travelled far and wide.


Epsom salt looks very much like coarse kitchen salt. But make no mistake, they are entirely different in molecular terms. Epsom salt is also used in health and beauty products in the form of bath salts, exfoliators, muscle pain-relievers, migraine-relievers, and those that treat cold and flu symptoms. Be cautious not to use these forms of Epsom salts to feed your plants, as they are often mixed together with all sorts of dyes, alcohols, aromas, and other ingredients that are likely to damage your cannabis plants. You will easily find the right product in any garden store, and even in pharmacies and health food stores.

Epsom salt is a fantastic and completely natural way of giving your cannabis plant an extra boost of both magnesium and sulphur, with the added benefit that you really can’t go very wrong with it. Excess feeding of these micronutrients will not have a negative effect on your plants. It is almost impossible to oversaturate the soil over time. Epsom salts also can be used in hydroponic systems; though here, you should be particularly mindful of potential pH swings.

It is very easy to use, easy to source, and cheap to boot. It is highly soluble in water, so it doubles as a great foliar spray. With the evermore urgent pursuit of completely organic ways of growing great weed, Epsom salts deserve an honourable spot in your arsenal of all-natural and environmentally conscious products.


There is no major difference in the magnesium found in Epsom salts as opposed to say, Cal-Mag supplements. The major difference is Epsom is an all-natural product while bottled supplements are usually petrochemical-derived.

High-performing crops have a tendency to exhibit some sort of deficiency if nutrition is not perfectly tailored. Cannabis certainly is one of these crops. In particular, plants grown hydroponically tend to exhibit a higher propensity for magnesium deficiency. Even is soil, certain strains seem to complain and demand a considerable boost of this micronutrient to maintain lush green foliage and vigorous growth.

Magnesium also facilitates the uptake of nitrogen (N), phosphorous (P), and potassium (K). Should a magnesium deficiency occur, it is easy to detect due to the characteristic yellowing of the leaves, except in the veins. This contrasts with the typical nitrogen deficiency, where the entire leaf turns yellow. Magnesium deficiency also tends to manifest first in the lower sections of the plant, with the yellowing leaves curling slightly upwards.

Magnesium is also highly implicated in photosynthesis, as it facilitates the creation of chlorophyll. It also strengthens cells walls, which are responsible for plant vigour and steady growth.

Magnesium is essential to achieve those superbly high yields. To form big buds, you need a healthy dose of this element. Furthermore, magnesium is essential for seed formation, too.


Sulphur is one of the building blocks of the plant’s immune system. It is also what gives garlic and onions their pungent tinge on the tongue. For cannabis, it works together with magnesium to increase the uptake of NPK, and is implicated in the production on enzymes, amino acids, and vitamins.

Chlorophyll also requires sulphur; but an area where this element is of particular interest is when keeping mother plants. Sulphur helps to promote longevity and reduce environmental stress. Mother plants are kept in veg for inordinate amounts of time. As cannabis is not a perennial species, this can pose a nutritional challenge, and Epsom salts certainly alleviate the issue of constant maintenance.


Epsom salts are very forgiving. As mentioned, it is difficult to overdo. But as with all things, little at a time goes a long way. These salts may be cheap, but costs do add up.

General rule of thumb would say 1 tablespoon per 5 litres of water can make for a great foliar application every other week. Difficult soils that have a pH above 7 will naturally lock out calcium and magnesium ions, so amending with some Epsoms salts is a great idea.

A more diluted version of Epsom salt water can also be used to help with seed germination, and even to help clones root faster. Harder-to-clone strains have been known to have a higher success rate by both misting and adding this mix to the actual cutting.

In the case of treating a deficiency, you should allow 3 to 4 days before evaluating the results by verifying new growth patterns and recovery from the less-affected leaves. More-affected leaves may well be scarred by magnesium deficiency and never fully recover.


As a final note, agricultural-grade Epsom salts are of great benefit to humans too. It is the base ingredient to fancy bath salts and many health and cosmetic products. Feel free to experiment with some of its known applications, should you need some relief from various common ailments. Now you and your plant can bond even further by using something in common.

Epsom salts get their name from the spring water of Epsom, England. But what exactly do they do for cannabis plants?

What Is Epsom Salt And Why Is It So Important For My Cannabis Garden?

There are many different ways to modify your garden into a more organic, natural environment for your cannabis plants to live in. Using natural ingredients is one way to ensure the best quality plants, and luckily for you, there are plenty of natural sources for your plants to get all the nutrients they need. Here, we will be looking at Epsom salt for cannabis growth and what it can do to benefit your growing ambitions.

Origins Of Epsom Salt

Epsom salt, the nickname given to magnesium sulfate, is a compound that was discovered in underground springs in the town of Epsom, England. It is a natural and organic source of both magnesium and sulfur. Epsom salts are commonly used in bath salts, exfoliants, muscle relaxers and pain relievers. However, these are different from Epsom salts that are used for gardening, as they contain aromas and perfumes not suitable for plants.

High THC Strains

Why Should I Use Epsom Salt For Cannabis?

Using Epsom salt for cannabis plants is extremely important for those who want to begin implementing more organic ingredients in their gardening habits. When using Epsom salt for weed, it’s almost impossible to overfeed your plants. At the same time, it provides them with a healthy dose of micronutrients that are crucial for strengthening their cell strength and overall immunity.

A Natural Source Of Nutrients

Epsom salt is an excellent addition to your gardening routine, as it’s a natural source of two of the most important nutrients for cannabis plants: magnesium and sulfur. Using Epsom salt for cannabis will allow a gardener to rely less on synthetic nutrient supplements or specialized, fertilized soils. Adding organic ingredients like Epsom salt to the diet of your cannabis plants will therefore ensure healthy soil and a healthy lifecycle.

Easy-To-Grow Cannabis

The Importance Of Magnesium in Epsom Salt

Epsom salt is a natural source of magnesium – one of the most important nutrients to a plant’s life, as it encourages its uptake of essential nutrients like nitrogen, phosphorus and potassium. Magnesium is also important for your plant’s development of chlorophyll, the component responsible for your cannabis’ ability to absorb sunlight, which allows photosynthesis to occur by strengthening cell membranes. Overall, a healthy level of magnesium is what’s responsible for the successful and healthy growth of your cannabis plants.

Autoflowering Cannabis Strains

Why Do Plants Need Sulfur?

Sulfur is the essential basis for your plant’s immune system. Sulfur facilitates the production of amino acids, enzymes and vitamins in your plant, all of which aid in the healthy growth of a plant and build up its immune system. In other words, a healthy base of sulfur in your garden will help prevent your plants from getting sick. Sulfur is also essential for your plants to create chlorophyll. Most importantly, it works together with magnesium to secure the plant’s uptake of nitrogen, phosphorus and potassium, or NPK – the most essential nutrients to a cannabis plant’s survival.

Bring Epsom Salts Into Your Garden To Prevent Deficiencies

Now that we know why magnesium sulfate, or Epsom salts, are so beneficial to plant health, we can apply this knowledge to our own marijuana grow ops. Using Epsom salt for cannabis gardens is an excellent way to prevent or treat magnesium deficiencies that will negatively impact bud growth, or sulfur deficiency, which can harm plant growth and cause discoloration.

The Right Time To Incorporate Epsom Salt

You can begin using Epsom salt for cannabis plants within the beginning of each lifecycle, when the plants are just a few inches tall. You should, however, cease using Epsom salts during the first week of flowering, as this can alter the growth of buds. Generally, a good amount of magnesium and sulfur throughout a plant’s life will ensure a high yield.

How Much Epsom Salt To Apply And How?

The ideal amount of Epsom salt for cannabis plants is one tablespoon per 5 liters (1.3 gallons) of water, or about one teaspoon per 3.7 liters (1 gallon) of soil. You can use Epsom salt for weed growth as a topical foliar spray when diluted with water, or incorporate Epsom salts directly into the soil or substrate. It’s a great way to prevent or treat magnesium or sulfur deficiency.

Start Using Epsom Salt Now

Epsom salt is an excellent way to ensure proper nutrient levels in your garden by using natural sources for organic ingredients. As proper levels of magnesium and sulfur are critical to healthy cannabis plants, using Epsom salt for cannabis can be considered a necessary addition to your gardening shed. Whether you want to start a new substrate or are looking for a natural way to cure some nutrient deficiency, Epsom salt and marijuana makes for the perfect team.

Here, we will be looking at Epsom salt for cannabis growth and what it can do to benefit your growing ambitions