Designing My Own Indoor PVC-Free Hydroponics System With Small Footprint & High Yield

March 29, 2021

By Kate Moore

Share on facebook
Share on pinterest
Share on twitter
Share on email
Designing My Own Indoor PVC-Free Hydroponics System With Small Footprint & High Yield

The grand plan is a fully self-sustaining and self-sustainable homestead. I’ll tell ya all about it when we get there. For now? We live in the Orlando suburbs with a tiny mulched yard in a house that we rent. Anything that I do has to be small enough to fit the space and temporary enough to take with us when we move down the road. However, recently I’ve gotten the bug to get going on a garden anyway. Gardens typically take space and require some level of permanence, so deciding how to go about it has been a bit of a challenge. But the rewards are worth it.

You see, the thought of being dependent on Amazon as my family’s food supply freaks me out a bit. We shop primarily at Whole Foods, which is owned by Amazon, and I receive near daily grocery deliveries via Prime.

Since an indoor garden with a small floor print and high yield is a must, I decided to go the hydroponics route. And since I love a good project, the idea on Friday to go ahead and make this happen “soon” turned into a weekend fully obsessed and immersed into the world of hydroponics, the Home Depot website, and designing the perfect system for the 40 different types of organic seeds I bought. All-in and over-the-top is kinda my thing.

Today officially marks Day 3 of my project. The system is designed, all of my materials are purchased and en route, and my husband has (begrudgingly, at first) been enlisted to aide me in putting it all together this upcoming weekend.

Hydroponics 101

In case you’re not familiar with hydroponics (or aquaponics or aeroponics), here’s a brief overview.

Plants are grown in a soil-free environment, and the roots are supplied with nutrient-filled water and oxygen in the dark to allow the plant to grow. The dark is also important because it prevents algae from growing inside the plant container. Because the plants don’t require soil, they also don’t need as much space and can be grown closer together for a higher density of output.

There are many different ways to set up a hydroponics system. You can buy fancy vertical grow towers for several hundred dollars a piece. Most home-built systems use PVC pipe in vertical columns or horizontal stacked rows. Hydroponics can be used to grow one plant in a container or a series of plants connected to a water source. It’s an extremely versatile method of growing plants that offers everything I’m looking for: small footprint, high density, high yield, low cost, and indoor compatible.

PVC-Free, Please!

My first notion of building a hydroponics system in my home was that it would be a straightforward process. I figured since so many people have already done this, I wouldn’t have to reinvent the wheel. Check out some designs online, order materials, put it together. Simple!

Actually… once I started researching a bit into hydroponic systems, I wasn’t liking what I was seeing.

The ready-made grow towers are more expensive than what I’m looking to spend right now, and I they’re not particularly space efficient. They’re also made entirely of plastic, which is a material I want to avoid when it comes to my food. It can cost $700 or more for a system that holds 25-30-ish plants. Double the plants, double the cost. Not the ideal solution for me!

On the other hand, the DIY builds on YouTube were even worse. Every system compact, multi-plant system was made out of PVC! PVC plastic piping is just about the worst material when it comes to chemicals. It’s chock full of a long list of nasty stuff and has been known to leach. That means the water supply and plants would be absorbing chemicals from the system. Also, a popular construction method involves gently melting the plastic to create cupholders for the plants which off-gasses all kinds of horrible stuff for the builder to breathe and adds to environmental air pollution.

I don’t want my family or my plants to absorb any form of PVC or its components, so it was quickly not an option. And really, I’m surprised it is such a popular option as PVC is clearly not food grade regulated plastic and known to release carcinogens.

Brainstorming A Plastic-Free Design

First, I had to settle on the type of structure I wanted. Ultimately, I kept coming back to the vertical set up with a wide cylinder for plants to fit all the way around. It was clearly the most viable option to keep the footprint small and efficiency high. Truly, what I want is a 100% plastic-free hydroponics system. Throughout my design process and research, I decided to settle (for now) on reduced plastic but PVC-free hydroponics. I’ll tell you why.

From what I can tell, plastic-free hydroponics really isn’t being done. I dug deep into the recesses of the internet looking to see what else was out there. It seems to all be plastic-based in some form or fashion.

I think it really boils down to cost as far as materials go. My husband and I put our engineering brains together to devise our own alternative design that was plastic free and have several ideas about how to make it work. The problem we had in common with each was cost.

Glass panels with food and water friendly framing? Stainless steel or copper piping of 12″+ diameter? Wood lined with something mold resistant and food friendly? Sun-dried, hand-crafted terra cotta?

At worst, we were looking at lots of dollars for speciality or custom-made materials. At best, we would be spending several hundred dollars on a risky experiment. The in between options involved buying expensive new tools and devoting lots of extra labor hours.

Our #1 idea was a cork lined interior supported by a wood lattice frame. Cork is mold resistant and doesn’t retain water. It can also be food friendly (hello, wine!). The challenge was that any cork sheets I could order online were probably not food grade, and I didn’t know anything about the manufacturing process as far as chemical use and safety. Plus, Amazon isn’t exactly known for the highest quality of products.

Again, we were back to custom or speciality materials at a not so pretty price tag.

Why I Compromised With Plastic

There came a point in the conversation where my husband became exasperated, “Why don’t we just use PVC? It’s obviously the superior material for this type of structure. It will be cheap and easy. Will it even affect the plants?”

My response was a simple question, “Would you drink out of a PVC cup?”

His answer was obvious. No, neither of us would. So we wouldn’t make our plants do it either. Especially because we want to eat them.

While going PVC-free was a dealbreaker, we were both weakening our resolve on building 100% plastic free. I had devised a cost-friendly 20-gallon glass reservoir for the water and planned on making an alternative mount for the plants so I didn’t have to use the popular plastic net cups. The only plastic we hasn’t designed out was the tower itself.

(Truly, initially I wanted to design my system to be electricity-free, too. However, without an electric water pump, I would need to use gravity to feed water from the reservoir to the plants in the tower. I quickly realized that raising a glass 20-gallon tank above a 5-foot structure in my kitchen is not feasible. 20 gallons of water weighs about 160 pounds.)

Because there would be no standing water touching the tower, we compromised on using food-grade plastic. I figured that a lot of the produce I buy at the grocery store is packaged in plastic, and there’s a good chance the farmer uses plastic storage at some point in the process, too. The benefits of keeping the initial costs down, learning to grow my own food, and having super fresh, well nourished food outweighed how I felt about using plastic at all. Hopefully it’s an upgrade from the life the grocery store plants are living.

I’ll keep my plastic-free dream alive for Tower 2.0 down the road.

My Hydroponic Tower Garden Design

Ultimately, my favored design was to stack food-grade plastic 5 gallon buckets into a tower with holes cut into the buckets. It was a design I found in one lone PVC-free hydroponics YouTube video. I based my design on that material for my main structure and changed just about everything else from what this guy had done.

I found a glass fish tank with silicone edging to use for my water reservoir. The pet store turned out to be much cheaper than anywhere else selling them. A pump (also plastic, meh) connected to a silicone tube will channel water to the top of the bucket tower with an 8″ rain shower head. It was important for me to keep the reservoir separate because our water supply and pump should be able to support at least 3 towers. That means less upkeep as far as maintaining water nutrients and refills, and it’s more economical to have one pump and timer for the entire garden.

I’ve yet to decide exactly how the plants will sit in their holes. The PVC designs use angled pieces to direct the plants out and up. I’m planning on creating netted pots out of slashed cheesecloth or compostable seedling cups, however I’m not sure yet how to attach them at the best angle for the plants to have support and keep water from leaking out of the holes. I have a few ideas but per my usual MO will wing it when I get to that point in the build. I’ll let you know in the update what I come up with.

Overall, the footprint for the system with one tower will probably take up about 2’x3′, accounting for plant growth. The buckets themselves are only a square foot or so, and the fish tank is 13″x30″. There was a shorter option, but it was taller to keep the same volume. I suspect that the finished product may be about 6′ tall as the fish tank underneath everything will account for the first 15″ or so.

Each tower will hold at least 50 plants, but I’ll know my numbers for sure once I have my buckets in hand.

Coming Soon…

All of the parts and pieces should be in hand by Friday this week, so the project will hopefully come together this weekend. Once the thing is actually put together and functioning, I’ll publish a full materials list and share pictures of the final product. I went a bit overboard on buying seeds (so much variety!), so I’m ready to get going!

Stay tuned!

Continue The Conversation…

Follow me on Instagram @katemitchellmoore to join the community & conversation.

Share on facebook
Share on pinterest
Share on twitter
Share on email

This article is for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. These statements have not been evaluated by the Federal Food & Drug Administration. These information and products are not intended to diagnose, treat, cure, or prevent any disease.