Chemical vs. Natural Nutrients
4 min

What's The Difference: Synthetic Vs. Natural Fertilizer

4 min

Synthetic vs organic fertiliser is a heavily debated topic when it comes to growing cannabis. So let’s take a look at the advantages and disadvantages of each.

Which cannabis nutrients are best, is a tricky question. Unfortunately, the short answer is: it depends. However, we shall endeavour to carefully analyse the pros and the cons of both organic and chemical nutrients. Then you will be in a position to evaluate which fertilisers will work best in your grow op.

Of course, a blend of organic and chemical nutrients is possible and preferred by many indoor and outdoor growers. We can’t dial the nutes in for you, but by the end of this blog, you will have a few ideas on how to devise a customised feeding schedule for your marijuana plants.


What Are Organic Fertilisers?

Straight away it is important to understand that the word “organic” doesn’t mean the same for fertilisers as it does food. Organic fertilisers are products that have their nutrients bound up in their natural forms, such as plant and animal waste, having gone through minimal processing. This often means they are a lot more natural, and more akin to what your cannabis would naturally find in soil when compared to the heavily process and refined synthetic fertilisers – which are often made from petroleum.


For the soil grower, organics is the way to grow indoors or outdoors. Most cannabis-specific soils have a perfect N-P-K ratio for cannabis plants and sufficient nutes for the first 3-4 weeks. Enzymes, beneficial fungi and silica are usually the only liquid supplements the grower needs for the vegetative phase.


Most ganja farmers, even if they are sowing seeds directly in the dirt of their plantation, will amend and improve the soil in advance. Although some growers will have the time to mix liquid organic fertilisers. Many do not, especially if the crop is large


Avantages  A potentially better end product

The first major advantage of using organics when it comes to cannabis is the end product. Anything you feed your cannabis is ultimately going to end up in the bud in one residual form or another, and whilst this isn’t going to be a concern for the cannabis plant itself, it may be for you. It is widely thought that synthetic fertilisers can make the end smoke much harsher. For this reason, synthetically fed cannabis is often flushed before harvest, though it is impossible to remove all ‘contamination’. This is much less of a concern with organic fertilisers, as they don’t leave chemical residue – resulting in what many believe is a smoother smoke.

Avantages  Lower start up cost

A basic organic nutrients pack, a half dozen plastic pots and a couple of 50l bags of soil will set you back less than €100. Simple base nutes and a few stimulants are usually included in most brands box sets/bundle deals.

Avantages  Less risk of overfeeding and toxic build up

Organic fertilisers tend to release their nutrients very slowly, making it hard to overfeed your cannabis. Next to this, they do not often leave residual salts and acidity within the soil as they are natural, helping prevent toxic build-up and maintaining its health.


Inconvénients They are slow, sometimes too slow

The nutritional release of an organic fertiliser plays by nature’s rules, and doesn’t always provide as soon as you need it. It is more of a long-term game plan, and will give a constant but slow release.

Inconvénients Often unsuitable for hydroponics

Organic nutrients have a horrible tendency to cause all kinds of problems when introduced to hydro systems. Blockages and clogs are common problems. A 100% organic nutrient hydro grow will be something difficult to manage and you may not get that great results. A mix of chemical and organic nutes is the best compromise for now.

Inconvénients Beware of rip offs

All kinds of eco-friendly gunk, from simple molasses to exotic bat guano, are on the market labelled as 100% organic wonder elixirs. The best advice is to stick with the reputable brands and products with a proven track record. Research before investing too much cash. Just like other commercial organic products, a premium price is usually associated with many of the organic nutrient lines, so shop around for deals.

Related article

Using Coconut Water As Organic Cannabis Fertiliser


What Are Synthetic Fertilisers?

Synthetic based fertilisers are manmade, heavily process products that have been created to have a very specific and controlled content. They are often made from extracted petroleum and natural gas by-products. Being so specific in nature offers them lots of advantages, but comes with various drawbacks as well.


Most growers, even soil growers, will use at least one or two chemical fertilisers or supplements. The majority of hydroponics cultivators swear by incremental doses of synthetic feeds starting at 10-25% dosage from the very beginning. In contrast, the mostly organic soil grower sparingly adds synthetic bloom boosters to bulk up harvest weights without compromising flavour.


Chemical fertilisers are not favoured by most outdoor cultivators these days. They work just fine, but organics is in these days. Some synthetic stimulants can be added to speed up blooming and fatten up colas but that’s as far as most go. Generally, chemicals are associated with last stand struggles to fight off a pest invasion in the cannabis garden.


Avantages  Strong and specific

Unlike organic fertilisers, synthetic based ones have a strong and specific content, allowing you to know exactly what you are giving your cannabis plants in term of nutritional content and ratio – a big advantage to veteran grows trying to control a grow right down to the last detail.

Avantages  Easier to achieve a higher quality

Because of their composition, the nutrients within synthetic fertilisers are available for immediate absorption, allowing you to ensure your cannabis is getting what it needs, when it needs it. Thanks to the greater levels of control offered by synthetic fertilisers, it is often easier for beginners to produce an overall better quality grow.

Avantages  Huge yields for hydroponics

It really is true that huge hydroponics harvests can be cropped in about 75% of the time it takes to grow weed organically in soil. This is primarily because in a hydro set up plants roots can rapidly absorb far more of the available nutes from the oxygenated water. Plus chemical nutes are more hygienic and less problematic than risking organics in the reservoir.


Inconvénients Potentially produces harsher bud

As touched upon in the organics section, it is believed that chemically based synthetic fertilisers leave a residue within cannabis plants. Connoisseurs can always tell the difference between organics and hydroponics. Even if the grower has thoroughly flushed the marijuana and harvested with the greatest care, hydro weed tastes like hydro weed. Similarly, soil-grown cannabis tastes better and can be more easily flushed when fed organic nutes.

Inconvénients It leaves toxins in the soil

Synthetic fertilisers are often very acidic, and leave salt residue in the soil. This effects pH drastically, and often requires active maintenance to keep soil safe, healthy and salt free. If left with a salt build up, nutritional absorption can be affected, resulting in malnourishment.

Inconvénients Can be difficult to dial in

If you happen to be using exclusively inorganic fertilisers, it can sometimes be difficult to keep pH and EC levels within optimal parameters. Organics are much simpler and usually require far fewer bottles of nutes to mix coming feeding time.


There is nothing taboo about blending cannabis feeding with a combination of organic and inorganic nutrients. In fact, as alluded to above it is pretty commonplace in all kinds of grow ops.

Related article

Should You Grow Cannabis Using Soil, Coco Or Hydroponics?

Hydroponic growers add a touch of organics for flavour and soil growers’ bulk up buds with synthetic boosters all the time. Striking the right balance between organic and synthetic nutrients can deliver the heaviest harvests of the most flavoursome marijuana.


When it comes to making a decision between the two, there is no right or wrong answer. Which type of fertiliser is best is a heavily debated topic, and it will basically come down to what suits your needs the best. Do you want a natural grow that is kinder to the environment and soil? Or do you want complete and utter control of what your cannabis is being fed? At the end of the day, you need to pick what suits your situation.

Adam Parsons
Adam Parsons
Professional cannabis journalist, copywriter, and author Adam Parsons is a long-time staff member of Zamnesia. Tasked with covering a wide range of topics from CBD to psychedelics and everything in between, Adam creates blog posts, guides, and explores an ever-growing range of products.
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