Questions about NFT setup

[Tahoe227]

I am working on constructing a small NFT hydroponics system from scratch using PVC piping in an indoor space with decent but not perfect sun. I have two questions about this. What nutrients should I use, and can I use paper towels on the bottom of the pipe in place of capillary matting?

Thanks in advance.

[GpsFrontier]

What nutrients should I use

just about any commercially made nutrients designed for hydroponics should work fine. Just get nutrients designed for the type of plants you plan to grow. Vegetative nutrients for non flowering plants, Bloom nutrients for flowering/fruiting plants. And/or a combined (Vegetative/Bloom) nutrients for continuously fruiting plants like peppers, tomato's, strawberries, etc..

can I use paper towels on the bottom of the pipe in place of capillary matting

Well first I have never seen anyone using any type of matting in a NFT system, any type of mat would block the water flow. Second, I wouldn't put any type of paper in it because it will just dissolve and eventually just clog the pump and water lines. Not to mention turn the water cloudy with all kinds of particles floating in it.

[Tahoe227]

Thank you so much. I am using 3 inch diameter PVC and was told that matting should be used, but asked here because I thought it might clog the root mat and nutrient "film". I also wondered if it would be possible to grow small varieties of tomatoes and peppers in a 3 inch tube if adequate nutrients were supplied. Generally larger root systems are a result of low nutrient or water absorption, so I was wondering if it were possible. I am primarily looking to grow leafy vegetables, but are root vegetables possible as well?


Thanks again for your help.

[GpsFrontier]

While it is true that a plants root system are often bigger in soil where they need to search out water and nutrients. You'll be surprised how big the plants root systems get in hydroponics when you actually see them. So don't under estimate how big the root mass will get. Personally I would never grow tomato's in tubing (unless it was at least 6 inch wide, and the plants spaced 5 feet or so apart), 5 gallon buckets each minimum. Small or determinate peppers, I would give them 3 gallons of root space each minimum. You can always grow how you want. No mater what you do, it will be a learning experience. I have a plan to grow small (3-4 foot tall) corn plants in NFT rows, but I need to do some testing to check spacing and root mass needs first.

I attached a picture of the root mass in a similar system I built years ago. That root mass was from 4 pea plants growing in flood and drain system with 4 inch wide ADS tubing.

[Tahoe227]

Thanks again. That's certainly a very large root mass for so few plants so I will make sure to be very careful if I do decide to grow tomatoes, but I will probably just try a variety of small peppers or perhaps small root vegetables like onions, potatoes, radishes, and beets if they are possible. Would a net pot inhibit the growth of these and would I have to use any kind of medium? Best of luck with your NFT corn though, I could not imagine doing something of that scale. Would you say there is a steep learning curve with NFT or hydroponics in general? I love learning new things but I'm worried about my plants failing.

Thank you so much for sharing your expertise.

[GpsFrontier]

There is always a learning curve when you try something new. How steep is really different for everybody. But I always say start small first, get some experience under your belt before expanding. You'll save both time and money. I wouldn't try growing root crops in a tube like that. It's just not a good system design for root crops, especially potatoes. One potato can clog your whole tube. Even the onions unless your talking about green onions. there simply isn't enough root space for them. And they should never be sitting in water or they can easily rot.

Radishes grow quite fast, and can do so in a shallow space. However a tube like that wouldn't be very efficient. If you just replaced the round PVC tube with a open rain gutter, filled the trough (rain gutter) with growing media like coco fiber (line the bottom with plebes), you could have a solid row of produce in the same space instead of a few here and there. you could do the same with green onions. However potatoes, bulb onions, and beats would all need a deeper root area. I would say at least 15 inches deep. The down side is they are all inexpensive to buy at the store, so is it really worth it to fill a large trough with growing media? I have a design to grow root crops like potato's, that doesn't use much growing media at all, and you don't need to pull the plant to harvest the produce (another system I plan to build). It's a simple concept and bit more of a complicated build, but I can't really think of another economical way to grow those type of root crops. Here is a link to a small simple system I through together to grow green onions and radishes with.

If I were to grow radishes again, I would probably use row's of rain gutters like I suggested earlier. I would probably use the same sand and vermiculite/Perlite mix for a growing media. However I would need to mount the rain gutter troughs on 2x4's to support the weight. That sand is heavy, but works well and is real cheap if you get it at the right place.

I also have a more complicated system design for growing green onions, but in a small footprint would give me plenty of green onions each week (40+). However I need to work on the germination rate make it as productive as it can be. I think I have a simple Idea to germinate them without much labor transplanting them into the rotating system, but haven't tried it yet.

With the corn the variety I planed on grows about 3 feet tall and should produce about three ears per plant, and I think said goes from seed to harvest in 6-8 weeks. I planed to have rows. As an Example: If I had 8 rows, and the plants spaced 2 feet apart, that's 6 plants in each 10 foot long row. I should be able to harvest one row a week, and replant it. That should be about 18 ears of fresh corn a week. I can at least double that production (harvesting two rows a week) with a separate prorogation area for starting seedling transplants. Again I just need to work out the best spacing, system setup, and root mass accommodations. During summer corn is fairly cheep here, but I can grow it year round in a greenhouse. Just a little trial and error, and some math to see how profitable/economical it would be.