Deep Water Culture

Hydro/aquaponics gardening using recirculating deep water

When it comes to making a garden, most of the world relies upon the traditional soil methodology. Yet, for a growing number, the hydroponic gardening system is quickly becoming an ideal method in which to produce self-sustaining plants and food.

The learning curve is steeper for Hydro but once the fundamentals have been understood, it’s actually much easier than standard soil gardening!

Basically, there are three types of hydroponic gardening systems.

• nutrient film technique
• ebb and flow
• deep water culture

And while there are many who would state that the best way to learn is to jump all in, I found out that is pretty much needlessly learning the ‘hard way’.

One, if the person is not properly trained he or she will not see good results. Two, if the person finds the method too difficult they probably won’t stick with it long enough to see how beneficial it can be. Therefore, starting at the bottom and working to the more complex systems is sensible.

To work with hydroponic systems you will need only to understand the basics of water and how to balance the pH of the water. And where you will have to learn a bit about suspended plants (as they are in water) and in the regulation of the nutrients, you can at least get started if you know the basic steps.

If this sounds a bit overwhelming, don’t worry, I will walk you through the easiest of the three for beginning hydroponics, deep water culture.

What is deep water culture gardening?

Deep water culture hydroponics, or DWC as it is commonly called is the method of using water, usually a plastic storage container or a bucket that’s specifically designed for DWC. Then having the roots of the plant suspended in the water providing those plants with an easily bio-available form of nutrients for the plant.

There are a few very essential things to understand with this hydroponic system:

· Water: This will be replacing the use of soil. Using water as a medium, it’s much more convenient to acquire and dispose of when done. No more hauling around back breaking bags of dirt.

· Nutrients: It’s really amazing how much easier it is for plants to access needed nutrients when soil isn’t a factor.

· Oxygen: Plants need a certain amount of oxygen. Soil is usually aerated and there are pockets of air in the root zone allowing the plant to survive. In Hydro, without oxygen, the plant will drown. We need to introduce air into the water solution by using a standard aquarium air pump and airstone.

The benefit of Deep Water Culture is that the extra deep volume of water that the root mass is submerged in allows the pH and nutrient ppm (parts per million) to be more stable. This keeps things easy for both you and the plant.

Keep in mind, growing with recirculating deep water culture methods goes beyond just sticking some toothpicks in a carrot top and putting it into a water filled mason jar.

To have a successful dwc hydroponic system you will need to ensure that the plants have oxygen, water, and nutrients in the correct proportions by making adjustments to the nutrient solution at regular intervals.

Other Hydroponic systems run a little differently than this and are a little harder for a novice hydroponicist. But we will cover those later!

Why not just garden?

For any serious gardener wanting to further understand how to grow better plants, hydroponics provides that exact opportunity. If your business is in growing valuable cash crops, hydro can help give you greater, quicker yields often with noticeably less work. 

Only in Hydro can you experience a whole new world of gardening and growing potential. Through measuring pH and ppM levels everyday, your plants will literally be telling you what they may need or how they are reacting to your grow schedule.

You can reap these benefits from any Hydro system that you run correctly. The recirculating deep water system is generally the most flexible and easy to run for novices and professionals alike.

The DWC system allows for rapid growth of plants compared to soil. If you want to see how well a plant can do, put it in Hydro! You will get huge vegetables, luscious greens, savory herbs and resinous flowers that you seldom see grown in soil.

The DWC setup and maintenance is far easier to maintain than the traditional method. There is very little maintenance with a Deep Water Culture system and just a little more with a recirculating deep water system once its all set up.

The only real drawback is that small reservoirs can be more difficult to keep the pH and Nutrient ppm stable. But practicing adjusting reservoirs will just make you better at Hydroponics.

How to get started

To start your deep water culture system you will need to have about $50 to spend on equipment. This equipment will include a reservoir, which can simply be a plastic tote tub, an air pump, and air stone, tubing for the air pump, hydroton, and net pots. Now, you can use a 5 gallon bucket for your reservoir and you will be fine. The main elements which you cannot skimp on are the hydroton and the net pots.

To set up the system:

1. Connect the air pump to the tubing and then connect the tubing to the airstone. This will ensure that you get the circulation and the aeration of the water done properly.

2. Put your plants into the netpots. It’s easiest to start with aeroponic clones. If you only have seeds, the best medium to get those rooted and into hydro will be to start the seeds in Rock Wool. Once the seed has visibly sprouted you can easily add the seedling’s Rock Wool cube into the Netpot and surround it with Hydroton.

Once the roots start to grow, they will expand into the water and will draw upon the nutrients in the water. Immediately your seedling gets needed nutrients, plenty of water and you will see rapid growth.

3. Keep the roots below water at the seedling stage. So long as the water is above the roots, the plant will survive. Once it’s older and the root mass has developed, it’s okay that the top part of the roots are periodically a few inches above the water.

The roots will simply wick water upwards. Once your plant is in full growth, there will be days that you have rapid water uptake, so it’s important to keep an eye on the reservoir levels.

Once you’ve mastered DWC, upgrade to a recirculating DWC

Once you’ve mastered a basic deep water system, you may then be ready to replicate your fantastic results. You can easily upgrade to a Recirculating DWC which will allow you to maximize the number of plants which can be grown from one system.

It’s larger than the standard DWC and allows the grower to have 10 or more buckets simultaneously in one closed loop system using a single shared reservoir. So instead of maintaining and checking 10 different reservoirs, all you have to check on is one.

The main difference between the deep water culture system and the recirculating deep water culture is that the recirculating system, the water is pumped from one large reservoir through the system and then back to the reservoir. The only part of the system which is changing from the standard DWC is the re-routing of water back to the head of the buckets. Hence the re-circulation.

Adding the top feed Bubbleponic method to your Recirculating Deep Water Culture System

It sounds a great deal more complicated than it is. Bubbleponics is simply taking some tubing or an irrigation hose and running one tube to each individual net pot in your system.

This is generally used for when a plant is in it’s early vegetative stage and you’re wanting to encourage root growth. It will require you to have an additional pump and hose system attached to the reservoir, but this is relatively cheap.

Yes, you can go without the bubbleponics system, but in doing so you extend the time it takes for the seeds to germinate. Basically it’s an effective way of accelerating plant growth before the roots have fully grown into the water below the net pot. Here is how it works:

· The bubbleponics is set up so that the hose or the piping drips slowly from the top into each plants netpot. This gives the plant a sense of rain being applied to the seed.

· The top-feed method allows for the plant to receive nutrients from the water being supplied at the top of the plant as well as the nutrients being supplied through the water. Think of it as a saturation of nutrients.

· Once the plant has taken root and is primarily being fed from the water of the DWC bucket or tank, the bubbleponics serves as a booster, keeping it germinating quicker than the system would without such a device.

When using the bubbleponics top feed method you should occasionally check the pipes and the tubing for any accumulation of algae which can in time affect plant growth or a build up of nutrient sludge that could clog the piping.

Keep in mind that you are working with water and so any metal fittings will need to periodically be checked for rust. It is a low maintenance system, but it does still require maintenance.

A few considerations before you get started:

While there are tremendous advantages to having a deep water culture system, there are some downsides which must be addressed in order to allow you to make an educated decision.

1. The downside to this sort of system is that the PH levels tend to be a bit unstable, especially when one decides to have a single bucket system. The fluctuation of the PH levels must be monitored closely to keep the plants growing properly.

2. The roots of the plants need to have high oxygen and nutrients. It is not uncommon for the plant to “drown” in water if it’s not exposed to enough oxygen. Don’t forget that oxygen in the root zone doesn’t just keep the plant alive but also increases nutrient uptake making for more vigorous plants with better yield.

3. Water temperature on the smaller systems are prone to shift considerably and at a rapid rate. I would encourage those using this system to have a water temperature regulator so that the temperatures remain consistent if it’s located in an area subject to cold or heat.

Start small then go larger

My advice to anyone who is venturing into the DWC waters is to start with the simple 5 gallon bucket and get acquainted with the process of keeping the system going. Once you have the basics of the deep water culture system down, move on to adding an additional bucket.

The great thing about this system is that you can build as you need to and make the system larger as you go. Should you ever decide to go large scale, I would recommend that you look into the other hydroponic systems which are more equipped to do large scale gardening like the Nutrient Film Technique/N.F.T.

Useful tips and pointers:

• Nutrients

Be careful not to use nutrients with high amounts of organic materiel present. It’s important that you use a nutrient solution that is geared toward Hydroponic applications. If you use nutrients that are meant for use in soil you will most likely end up with infections in the root zone.

Hydroponic nutrients are pure and mineral based without any bacteria present. I know a lot of hydro growers always talk about General Hydroponics, and I’m going to go against the grain by recommending Cutting Edge Solutions 3 part system or the full nutrient line if you’re a connoisseur. In my experience it’s an affordable and effective alternative to the run of the mill General Hydro product line.

• Reservoir

Frequency of reservoir changes: There are a lot of factors that can determine this. A good rule of thumb is: Vegetables and leafy greens: At least every 10-14 days. Resinous flowers: Every 7-10 days. The other factor to consider is at what point are they in their growth stage.

Mainly if they are seedlings that are just getting started or are at the end of their life cycle and ready to harvest, then the reservoir change can be the maximum number of days.

Since nutrient uptake can be slower during these times. If your plants are in the middle of prime growth then more frequent changes will be necessary since in Hydroponics you will notice during these times that nutrient uptake can go through the roof.

Give them what they need and your yield will be astounding. If you notice Ppm/tds/ec levels dropping off too much before it’s reservoir change time, then it’s okay to add a little ‘top off’ of nutrients to bring them back to the proper ppm levels.

Also note that smaller reservoirs, less than 10 gallons, will need more frequent changes.

• Try to leave a couple inches of root above the water level, this will help encourage oxygen uptake. If you submerge the root entirely you could risk drowning your plants at worse and at the least will slow down growth.

• Reservoir water temperatures should be on average 65 F. If it gets below 55 F, the plant will slow down and much cooler than that will kill the roots. If it gets above 75 F, it will start cooking the roots, reduce oxygen in the water and encourage root zone bacterial infections. The only solution to either of these temperatures fluctuations will be to get a water warmer or water chiller.

• PPm/Ec/Tds for Deep Water Culture is the same for across the board Hydroponics. Generally 5.5-6.5 pH. Hydro always needs to be run at least slightly acid.

• If you want to speed up your crop from seed to harvest, then do Aero-cloning and skip the seedling stage!

Anything worth knowing has a learning curve. Just keep at it! Once you understand the principals of Hydroponics, it will seem very easy. You may even wonder why you didn’t try it sooner!