A few weeks ago my garden looked like the picture above, since then I've been getting a few decent salads from it a week. It's been a process to Automate the Garden and to optimize the garden. Now it's time to profit.
The process of going from seed to plate is a lot easier when you don't have weeds, dirt, poor weather or pests to deal with. It's been up to minus 45 outside so growing indoors is our only option for most of the year. The cost of fresh salad, herbs and vegetables are outrageous these days so we decided to grow some ourselves.
Building the hydroponics system cost about $300-500. Variable costs are around 25 cents a day in electricity and maybe 50 cents per plant in grow cubes, water, fertilizer and pH balancers. Lettuce is about $3.00 a head in the stores here, herbs are just as pricey. We could get 72 heads every 60 days, at a cost of $50 or total savings of just over $150.00 every two months. It doesn't take long to be in the money. Even if there are serious issues, a system like this can pay itself back in under a year.
Lettuce likes 5.5 to 6 pH. The tap water here if usually basic, or 8 to 8.5 pH because of the glacial waters. Alkaline gets even worse if you don't rinse the rockwool cubes. A cheap test kit lets you know if the water is right and some pH Down (safe acid) works to make your water more acidic, you could also pour lemon juice into the water.
The temperature in the basement is around 17 degrees which is fine. During monthly water changes we let the water sit for a couple hours before turning on the pump to get rid of the worst of the Chlorine, our home isn't too bad for it. Excessive Chlorine will kill some plants. Using rain water isn't an option in the winter and it's probably full of bacteria.
When you put the rockwool directly in the net cups, it can get too soggy, so I put some clay pellets at the bottom to raise them out of the water. You can put the seeds directly into the rockwool (green cubes) or sprout them. We use a wet paper towel in a dark place and an almost sealed bag for a few days. A sprouting tray also works. This isn't really necessary except if you are starting all the plants in one go.
When the system is going I move the larger plants to the top of the rack and keep the smaller ones or the seedlings at the bottom where the holes are closer. Staggering growth is important so you don't have 72 mature heads of lettuce at the same time. Wires allow the light source height to be adjusted. Light gets really weak if its not directly above the plants as these are only 30 watt tubes.
We use Organic 3-2-4 NPK plant food. When first starting out I got 7-9-5 which is a mistake because Phosphorous is for flowers so the middle number isn't necessary. Some people mix just Nitrogen and Potassium but I want to keep it simple. The Bok Choi and some other plants aggressively flower so keep the middle number down, N-P-K.
Those are some healthy looking roots. They can clog the drains reducing water flow which causes floods. I just adjust the inflow and lift some of the cups to get the roots out of the drains. Moving them around is simple. We also introduced algae into the system which happened by putting some basil bough from the store into here. It's okay, just cover the rockwool with tinfoil. It's harmless and fighting it is futile.
Waiting for the plants to grow takes time, but with an optimized system, good fertilizer and lighting it can go from seed to plate in less than 8 weeks. Having perfect control over what you grow is worth it as the plants taste pure. If you grow outside, pollution and soil quality is a serious concern. Birds and insects carry disease and cats use the garden as a toilet.
So, it's safe to say, I'm hooked on hydroponics 馃樄
