What are hydroponics?

Hydroponics is a soilless growing medium in which you grow plants in liquid. Generally they are grown in a nutrient solution mixed with water. Down below we teach you how to prepare a soilless growing medium. 


Preparing a soilless Media in 4 easy steps

      1. Start out with your base material, either peat moss or coco. Since both are mineral based, perline and/or vermiculite can be added to aid in aeration and water retention. 
      2. Add a mineral component at 5-10% of the total mixture ✱ (we recommend sand or clay as they are cheap and easy). Insoluble plant nutrients can also be added at this point (we recommend lime or rock phosphate). 
      3. Add compost at 10% of the total mixture ✱ (we recommend worm castings). 
      4. Prime the medium before planting with Future Harvest’s Royal Black. This will allow more time for the breakdown of the humic acid into fulvic acid, as well as chelate any nutrients present in the medium.  


✱ For example we want 100 liters of soilless medium so we’d make a blend of 80 liters of coco, 10 liters of sand and 10 liters of worm castings. ✱


Royal Black Organics Future Harvest

How often should I use nutrients

As a general guideline when growing with conventional nutrients in a soilless medium we recommend feeding the plants every other day and inbetween to give 2 rounds of straight water.  Feeding and watering are based on how much water the plant goes through. 


Pile of dirt


What does solubility mean?

Before we introduce the nutrients you have to understand solubility. Solubility is a nutrient's ability to be dissolved in water. Given this, nutrients that are insoluble need time to break down and in many cases take years to dissolve. This can be the biggest obstacle for organic growers but with a bit of knowledge and planning it can be overcome! 


What nutrients should I use?

We’re going to go through each of the nutrients one by one to provide you with organic options; however, when you are giving the nutrients to your plant, they can all be added together in the same feeding.
Note: when using compost tea, prepare it as normal and once the steeping is complete you can add the additional nutrients and feed via the roots. Additional humates can be added in order to aid in nutrient solubility and absorption. 

Nutrients that are insoluble need time to break down.


Sources of Nitrogen

    1. Animal Waste: unfortunately, animal waste is the most common and easily available source of organic nitrogen. Of these, fish emulsion is the most readily broken down and the easiest to use. 
    2. Plant based amino acids: these are another great option, but they can be difficult to find. 
    3. Sodium Nitrate: this mineral salt is permitted by some but not all organic authorities. It is high in nitrogen but the sodium component can stay in the soil and increase the salinity. Long term usage can result in serious damage to the soil. 


Sources of Phosphorus

As far as nutrients go, this is the biggest headache. There are no soluble forms of phosphate in nature; therefore, there is no such thing as an organic phosphate fertilizer that dissolves in water. Growers often use an insoluble source and do their best to free it up over time. Keeping a healthy population of beneficial microbes is essential for proper phosphorus nutrition. 

Some sources of nutrients are organic, but not vegan. 


  1. Bone meal: this source of phosphorus breaks down easier than rock phosphate. However, use of bone meal results in the grow not being considered vegan, which could be an issue for some organic growers. 
  2. Fruit bat guano: this source of organic phosphorus is most easily broken down and should be used as a dressing on top of the media. Because it is a very limited resource, the price is quite high.  

 fruit bat doing fruit bat things

 Fruit bat guano is a good source of phosphorus. 


Sources of Potassium

  1. Potassium sulfate: this is the most obvious choice as it is highly soluble, fairly inexpensive, and has no restrictions on its usage.

  2. Kelp: kelp contains decent amounts of potassium but may need extra time for the potassium to become available 


Sources of Calcium

When dealing with plant nutrition, organic or otherwise, calcium poses a problem as it reacts with other nutrients which results in them becoming locked. When searching for a source of calcium to use be aware of possible reactions. 

  1. Calcium Carbonate: this is the most common and cheapest form of calcium. It is the major ingredient in lime, egg shells, and oyster shells. Calcium carbonate can push up the pH, but the calcium can be freed up in an acidic environment. 

  2. Organical Magic: this organic nutrient by Future Harvest is OMRI Listed and is a soluble source of liquid calcium. It has been formulated based on the traditional cal-mag products used in the hydroponic industry.

Organical Magic from Future Harvest




Sources of Sulfur and Magnesium

These nutrients shouldn’t be a problem to obtain as both sulfur and magnesium are found in soluble minerals. Sulfur can be found together with several of the other nutrients and will be soluble - with the exception of calcium sulfate. 

  1. Epsom salt: otherwise known as magnesium sulfate, is a great natural source of sulfur and magnesium. 


outdoor growing




We will include all micronutrients together as they are risky so you may or may not want to fertilize with them. Micronutrients are soluble, however, they can be difficult to obtain. Consider feeding the micronutrients separately from your other nutrients; although they are soluble together, they easily react with each other and can fall out of your solution. 
If you want to work with micronutrients, look for the sulfate forms of:
  1. Manganese
  2. Copper
  3. Zinc
  4. Iron: pay the most attention to iron as it is needed in the highest amounts and can be very unstable. If brown particles are seen on the bottom of the nutrient mixing container, it is likely the iron has fallen out. 
  5. Boron: in the form of borax. It is a fairly easy option as it is cheap and readily available. 
  6. Molybdenum: this can most likely be left out, since the amount required is miniscule and it’s expensive and hard to source. 

Important Notes

This blog post is written with the small hobby grower in mind. If you are a larger producer, we strongly recommend you check out the local rules and regulations if the intention is to produce an organically certified product. What can and cannot be used, or done, will vary by jurisdiction and it is up to the grower to understand the regulations pertaining to them. 
For the hobby grower who doesn’t want to dive into the rules and regulations, we advise you to only use ingredients which have been certified by third parties such as OMRI or Eco Cert. Many fertilizer manufacturers print organic or natural on their label; however, without verification by a third party, it is impossible to know what is actually in the bottle. 

Make sure your products are organically certified by a third party! 

If the goal of the crop is to reuse the media and try to achieve a long term balanced environment, then lighter does of nutrient should be considered as there will be less risk of any build up! On the other hand, if reusing media is deemed to be risky due to concerns of transferring pathogens from one crop to the next, it is advised to recycle the media in a garden or lawn and start fresh. Keeping in mind, any nutrients freed up in the first round, especially phosphorus, will be discarded. 


Final Thoughts

Growing hydroponically with standard hydroponic nutrients is very straightforward.  Using organic nutrients can be a bit more challenging but with a bit of patience and an understanding of where the nutrients are coming from it should be fairly easy to grow a crop using this method.




If you need any help, remember you can always reach out to @futureharvestdevelopments on instagram if you have any questions or need advice.