Understanding the Nutrient Film Technique for Home-Based Hydroponics Growers

Interested in growing your own vegetables and fruits at home? If an outdoor garden isn’t possible, or you want a year-round growing season, then hydroponics may be the answer. However, there are numerous different systems and techniques out there, and you’ll need to make an informed decision about which is right for you. One option you’ll discover is called NFT, or the nutrient film technique. In this guide, we’ll explore NFT systems, their capabilities, benefits, and what crops you can grow with this type of system.

What Does NFT Mean?

In hydroponics systems, soil is replaced with nutrient-rich water. Plants grow in this water just as well as in soil. However, there are different techniques of providing the plants you grow with the nutrients they need. NFT systems are similar to ebb and flow setups, but rather than relying on slow water movements, the pump keeps the nutrient solution continuously moving past plant roots.

NFT systems all share a similar setup. At the top is the growing area. At one end, there’s an inlet for allowing the nutrient solution to enter. At the other, there’s a drain tube. This leads down to a reservoir where more nutrient solution is held, and where a submersible pump is installed. The pump moves nutrient solution up into the upper reservoir, where it flows over the plant roots, down the drain tube, and back into the main reservoir to start the process over again.

Unlike some other setups, NFT systems are active, which means they have moving parts. These will suffer from wear and tear over time, eventually requiring replacement. 

Benefits of NFT Systems

While all hydroponics systems offer advantages over in-ground growing setups, NFT systems deliver a few unique benefits. These include:

  • Does not soak plant roots
  • Ensures upper roots have access to oxygen to fuel faster growth
  • Thin film of water limits effects of evaporation
  • Less waste as nutrient film flows directly across roots

These advantages, coupled with the relative affordability of building this type of setup, make nutrient film technique systems popular with those just getting into hydroponic growing.

Grow Time Considerations

Grow time is one of the most important things to think about when investing in a hydroponics system. NFT systems offer a faster grow time than other setups, thanks to the fact that the plants’ upper roots have access to oxygen, and the lightweight nature of the plants best suited to these types of systems, which we’ll explore in a separate section. The grow time is usually just a week or two. However, understand that an NFT system is not going to provide you with all the plants you need to eat, because these setups are not ideal for use with fruiting plants. They’re better used with greens and other plants where you consume the stems and leaves. Microgreens are an ideal option, but you can also use this type of system to grow a number of other plants.

Plants Best Suited for NFT Systems

As mentioned, NFT systems are better for specific types of plants. Ideally, you’ll grow lightweight plants that do not have heavy root masses, or plants that bear fruits. There are a couple of reasons for this.

First, you want lightweight plants in these hydroponics systems because there is little support for larger, heavier plants. Also, the larger the root mass, the more nutrient solution will be blocked and absorbed, creating problems for other plants in the system.

Second, the thin nutrient film is not well suited for the nutritional demands of fruiting plants. These plants require very high levels of nutrients to grow their fruits, and this will deplete your nutrient solution quickly, requiring that you regularly replenish it. 

So, what plants should you consider for use in NFT systems? Some of those you might want to consider include:

  • Any type of microgreens, even fruiting plants, as they’re consumed before they mature to bearing age
  • Greens like Bibb, butter, and leaf lettuce
  • Kale
  • Spinach
  • Broccoli rabe 
  • A wide range of herbs

With that being said, some fruiting plants are better suited to these types of setups than others. For instance, commercial growers use a type of NFT system to grow strawberries. Modifications to the system, such as adding trellises, can allow you to grow heavier plants that bear fruit, such as tomatoes or squash. However, this leads to other problems, including fast depletion of nutrients in the solution.

If you’re considering creating your own NFT setup, the golden rule when it comes to choosing plants is to choose those that have short growth periods, limited root masses, and mild nutritional requirements. 


Drawbacks of NFT Systems

While NFT systems offer quite a few benefits, including affordability and ease of set up, they do have a few drawbacks that you should be aware of. These include the following:

  • Not well suited to growing larger plants, which limits what can be grown
  • Continuous nutrient delivery is not ideal for mature flowering or fruiting plants
  • System is dependent on electricity and moving parts (pumps)
  • System must run 24 hours per day, so power outages or pump failures could cause plant death
  • Growing fruiting plants even in a modified NFT system depletes nutrients very quickly, requiring near constant monitoring

In Conclusion

When it’s all said and done, hydroponics allows you to grow plants in climates where they would not otherwise survive, in areas where you do not have room for an outdoor garden, and during fall and winter months when outdoor plants would not survive. NFT systems are excellent options for those just getting started because they are relatively affordable to set up and can be used to grow a wide range of leafy greens, herbs, and other plants. However, they are not ideal for growing fruiting plants and ultimately will be just one of several types of growing systems you will require if you’re attempting to become self-sufficient.

Source:

https://www.greenandvibrant.com/nutrient-film-technique
https://www.thespruce.com/hydroponic-gardens-nutrient-film-technique-1939220