Fogponics 101: Is Fog the Future of Hydroponics?

Fogponics 101: Is Fog the Future of Hydroponics?
Contributor
Contributor
External Guest Writer
April 13, 2021

Hydroponics - the practice of growing plants in water rather than in soil - is a field ripe with disruption and innovation. While conventional soil-based farming techniques have been pretty much cut and dry in their methods for years, hydroponics continue to push the boundaries. One of the latest gardening trends to emerge - fogponics - is proving fruitful in the production of herbs and spices using fog instead of stagnant water or soil.

What is Fogponics?

Within hydroponics, there are three key categories of growing techniques farmers use:

  1. Liquid Culture Hydroponics: This involves growing plants in a liquid solution of minerals, and is what we typically first think of when we mention "hydroponics". There is no solid material substrate in the system.
  2. Solid-Media Culture Hydroponics: This technique involves the use of solid media like heavy pots and bags to facilitate plant growth.
  3. Aeroponics: This technique uses misters, foggers, and sprayers to provide a suspended plant root system with nutrient solution via fine water droplets.

Fogponics is a sub-technique of aeroponics. Plants, herbs and veggies grow thanks to nutrients that are delivered via fog. The fogponics system uses foggers, which pump and vibrate under pressure to transform a nutrient and water mixture into humidity, not dissimilar to the humid atmosphere one might find in the rainforest. This fog creates a constant nutrient-rich environment for plant roots.

A fogponic system allows nutrients to access all parts of the plant roots at all times, since the tiny droplets can travel into the crevices and tight spaces between densely packed plant roots that might be difficult to reach with other methods.

How Does It Work?

Fogponics differs from other aeroponic techniques, which may use sprayers or misters, in that it uses foggers specifically. 

On the surface, fogponics covers all the basics of hydroponics in a very similar way. Plants are given everything they need such as moisture, nutrients, and oxygen. Like in hydroponics, plants in fogponic systems do not need to search for these elements like they do in soil-based systems. Therefore, the plants can afford to put all their effort and energy into growing, flowering, sprouting, and fruiting.

Where fogponics veers off from traditional hydroponics is in oxygen and nutrient delivery. In hydroponic systems, oxygen is delivered to the plants via an air pump that keeps the water aerated. In a fogponic system, by contrast, plants are suspended in the air in foam trays, with their roots exposed. This gives them plenty of oxygen access, rather than being submerged in water oxygenated by an air pump. 

You can use a regular storage box to support the unit your plants are hanging from. Cut holes about 8 cm in diameter at the top of the lid to fit netted cups. Fill the cups with some sort of growing medium — like coconut coir, or coco pellets. This is where the plant roots will be held. Place your fogger inside the box to deliver nutrients to the roots.

Nutrients are delivered via foggers which usually run on a timer. The benefit of using foggers rather than sprayers or misters like in traditional aeroponics is that foggers can atomize water droplets into even smaller particles, usually less than 10 microns in size.

plants being grown in a novel farming system

The Benefits of Fogponics

Is there really that much of an advantage to using a fogger specifically, rather than a mister or sprayer? Surely all aeroponic systems have similar efficacy and productivity, so why bother with fogponics?

The truth is, yes. Fogponics beats out all the rest, and if you haven't set up an aeroponic system yet, here is why you should invest in a fogger and go for the fogponic set up.

When it comes to optimizing root growth, the variable that matters most is the size of the water droplet. If the average water droplet is too large, then not enough oxygen will make it to the plant roots. If the average water droplet is too small, then plant roots will not receive the necessary nutrients for growth.

There is a tradeoff between the delivery of nutrients vs oxygen to the plant roots via water droplets. That sweet spot for optimal delivery of both nutrients and oxygen has been found to be 30 - 100 microns in diameter. Water droplets below 30 microns need to be dispensed at extremely high density to be effective.

Sprayers and misters cannot provide those small droplets in the density needed to make them most effective. That is where foggers are the perfect tool for the job.

Additionally, many proponents of fogponics argue that providing water and nutrients in small particulate sizes results in much faster absorption by the plant roots, leading to faster plant growth overall.

Other benefits of fogponics include:

  • Increased air exposure to plant roots
  • A direct supply of fine nutrient solution to plant roots
  • Provide plant roots with absolute access to the carbon dioxide in the air, which is necessary for photosynthesis.

The Best Plants to Grow Using Fogponics

There are a range of plants you can grow using fogponics. Those that do best however seem to be herbs, small vegetables, leafy greens, and spices. Marijuana is also a popular plant choice for fogponic systems.

Here is a list of plants that are fogponic-friendly:

  • Basil
  • Beans
  • Chamomile
  • Chervil
  • Chives
  • Cilantro
  • Cucumber
  • Marijuana (if legal)
  • Dill
  • Kale
  • Lavender
  • Lettuce
  • Marjoram
  • Oregano
  • Rosemary
  • Spinach
  • Tarragon
  • Thyme
  • Mint
  • Parsley

For obvious reasons, shrubs or larger plants won't do well in a fogponic system. Fogponics can however be a great intermediate solution for transplanting young plants that don't yet have a root system, such as seedlings and clonings.

A young cutting does not yet have a well-developed root system, so it is very difficult to hydrate and provide nutrients to it using traditional methods. The amount of water applied must be kept to appropriate levels in order to avoid suffocating the cloning. Conversely, too little water can cause the new roots to dry out, meaning sprouts will never spring up.

Fogponics systems can supply fog that provides growers with a constant mix of small moisture droplets at controlled amounts - ideal for starting clonings off and supporting their root development.

Growing with Fogponics: The Best Tips

There are a few things to look out for and keep in mind when starting off with a new fogponic system.

Heat from the fogger will warm your environment

If you leave your fogger running continuously for a long stretch of time, your growing environment will likely warm up. This heat can then cause the fogs to dry up and evaporate, which adversely affects your growing root systems, which will themselves dry out if not addressed. 

Setting your fogger on a timer is a great way to overcome this issue. It is a simple and cheap solution. Set your fogger up to run in intervals - this way your growing environment has the chance to cool down between fogs. 

Watch out for build ups of salt

As in any aeroponics system, fogponic systems suffer from the side-effect of salt build-up over time. Salt can clog up the foggers, preventing them from fogging up the place as best they can. 

Regularly cleaning the foggers is the best way to combat this. Simply soak the foggers in vinegar or clean them with a toothbrush to help keep them running effectively.

Protect against power outages

As any hydroponic system, fogponics rely heavily on a constant and reliable electricity supply to run the whole system. One power outage can wreak havoc on the growing plants and can throw days and weeks of work away in just a few hours' time. That is of course unless you have a contingency plan.

Fogponics systems are especially susceptible to this, as without electricity, the fog cannot start, and so roots have nowhere to get oxygen or nutrients, and will dry out very fast. Death should be expected from within just a few hours of power outage.

Fogponic System and Hydroponic Systems: The Future of Farming

Fogponics can be an excellent way to grow herbs and small plants fast. It can prove an interesting experiment for hobbyist hydroponic growers, or a niche business model for the aspiring foodie entrepreneur.