DWC Hydroponics in the Greenhouse
So I found some pictures from where we were setting up some of our DWC, deep water culture, hydroponics that we ran this last season. We did a test run on several types of plants from okra, tomatoes, blue berries, peppers, cucumbers and squash. This was the first DWC test run I did to try out how our aerated worms teas would work for hydroponics. I was told that it would not work as the main fertilizer for the system since it is not potent enough. This was not what I found at all but remember all worm castings are not created equal. What goes in comes out and depending on your feed stock will decide you NPK and also your bacterial and fungal counts. I have found that the tea brews I had been working with in my DWC to be very potent. Here is a cheap little test just to give an idea of where the NPK ratings of my castings I use in my teas are.
I use those castings to brew and then add frass and several meals along with many other things to feed the microbes and increase what is lacking in my plants at that time. The results I got where actually really good and the opposite of what I expected from everything I had been told. It was not the worm tea that was the problem. One problem ended up being the heat and air temps here. In DWC you use an aerator to pump oxygen into the buckets where the roots sit to keep them from getting root rot and provide the plant with plenty of oxygen. The problem with this in area where you have very hot air temps is the temp of the air that comes out the air stones and threw the DWC system increases the temp of the water. The warmer water temps are a little harder to control PH and also your DO, dissolved oxygen, levels go down. In a larger system the air temp does not have as bad of an effect on the temp of the water as in a smaller system like DWC buckets compared to a large revivor with floating rafts but it will still raise the temp.
The pepper plants did fantastic and gave a nice heavy yield like most the other plants but once your PH gets to high the plants will stop absorbing nutrients and then you will have lots of problems and it won't matter what your feeding them. Come to find out my biggest problem was our well water. After several test and retest our well water sits right under 8 PH which is way to high for hydroponics and I was adjusting the PH twice a day. Since our outside water and hoses run directly off the well and does not go threw the house filtration system it is not suitable for hydroponics. After I get a larger filtration system in place for the outside water outlets I will be setting these systems back up in a greenhouse and giving them another run.
The white towers are Foody towers and they hold 40 plants. You can also add a small motor to make the rotate automatically if you wanted. I run two of these towers now and love the amount of production I get for the amount of floor space they take up. We have done several hydroponic and dirt stacking towers and the Mr Stacky ones work well for both and are much cheaper then the complete systems. You can add them to a bucket with some pvc pipe and a water pump to create a hydroponic system or just stack them and plant with dirt for an easy to water stacking grower.
I try to leave enough space between buckets to cage everything so we can fit around 30 buckets down each side and still leave space in the center for around 8 towers which is not bad if your getting 30 to 40 plants in each. Production was just a bonus with this one since we were really just trying to work out our systems along with which air stones and air pumps we preferred and how everything functioned. It turned out to be a pretty productive first go and produced a good amount of produce especially the peppers in the Foody towers.
We will be trying to setup hydroponic towers hanging from the walls in a temperature controlled shipping container this next year and adding LED strip lights for growth and trying to setup a swimming pool for aquaponics where we can have a larger fish area outside the greenhouse and pump the water in to the grow beds to maximize the growing space in the greenhouse and not waste space with stock tanks for fish. Once we get everything wired on our first shipping container and get our king crop fodder system back up and running we will be dropping the 2nd container that will run off the same power supply as the first. Can't wait to post updates as we go and probably be asking some questions from some of you experts that already have similar systems in place.