Tracking mistakes 2

Today following Zachary Jones and Jeff Edwards advice I checked pH level of rockwool that I used submerged in water. Result was unsatisfactory - about 7.5.

Such environment is too alkaline for spinach. As I mentioned in my last post optimal pH level for spinach is 5.6 - 6.0. It means that if I'll try to germinate spinach on rockwool in future I'll have to add some acid to it.

Tracking mistakes

By advice of Jan Wildeboer I've bought pH test and checked pH level of my nutrient solution. It turned out that pH level of my solution is about 6.

Optimal pH level for growing spinach is from 5.6 to 6.0. According to that I conclude that pH level of nutrient solution have no guilt in failure of my first experiment. There are two possible causes left - toxicity of mineral-wool and lack of light. Additionally Paul T. Juckniess explained that my plants was submerged too deep into solution and usually the crown of a plant do not tolerate being semi submerged. So next time I won't submerge my plants that deep. But in this specific case plants stopped developing earlier - before replanting them into hydroponic setup. This is why I assume that in my case problem was mineral-wool and lack of light. I will try to grow next stack of seeds on turf under natural sunlight.

Ending of 1st experiment

One week have passed since I replanted spinach seedlings into hydroponic setup. Till this week not only seedlings didn't grow at all but they've also became weak and withered. Unfortunately I had to admit that my first experiment failed.

I allow three possible reasons which led to failure:
1. Most possible that amount of light from one bulb is not enough for plants. Yet it has high intensity of light output but its spectrum isn't as wide as HID bulb's.
2. Germination took place on mineral-wool for construction purposes. I am not sure but it could possibly contain some toxic elements.
3. I never checked Ph level of water. I think that it was about normal because seedlings germinated. But to be 100% sure I have to buy Ph-meter.
My next step will be a try to grow seedlings under sunlight near window. Very soon I will buy HID bulb. Then I will be able to try growing under fully artificial circumstances again.

Replanting of spinach

One week have passed since I replanted spinach seedlings into bigger mineral-wool cubes and placed them into growhouse under artificial light. Unfortunately they didn't grow at all.

Roots of seedlings didn't grow also. I made a decision to replant small mineral-wool cubes into hydroponic setup and watch how growing will develop then. I filled container of my setup with nutrient solution and turned aerator on. Then I carefully replanted seedlings into ceramsite and placed hydroponic setup into growhouse.

Every following morning I turned light in growhouse on and turned off every evening.
I've also shot short video to show how aeration occurs in my hydroponic setup.

Spinach germination - stage 2

8 days yet passed since I planted seeds. 3 seeds out of 10 germinated and started growing, 2 more germinated but don't grow yet. Mineral-wool cubes became too small for those seedlings which started growing. But yet I didn't want to hurry with replanting them to hydroponic setup because they were still too small in my opinion. I made decision to replant them to larger mineral-wool cubes.

I made cutouts in large cubes for small ones. Before replanting seedlings I impregnated mineral-wool with nutrient solution. This time I dissolved fertilizer in proportions written in its manual. I thought that seedlings are ready for full dosage of fertilizer. I put box with seedlings to growhouse which I described in my last post. Every following morning I turned light in growhouse on and turned off every evening. Besides I regularly sprayed mineral-wool with fertilized water.

1st experiment - spinach germination

I have a keen interest in topics about hydroponics for a long time. A while ago I have decided to try it by myself. At first, I have chosen spinach for this experiment, because I have read that this plant does not require special care and attention. I put together a simple hydroponic setup that will describe in my next post. Before the cultivation of spinach I need to germinate the seeds. In markets I've seen special outfits for this, but I thought that I can design it by myself as well. I used a package of egg, garden box, and mineral wool. In order to proceed nutrient solution, I made holes in the bottom of each cell of egg-box and put a mineral-wool cube for each cell. Here is the result:

The next step was planting the seeds. Not recommended to plant the seeds of spinach immediately. They should be kept in water for at least 2 days, dried off and only after that you can plant them. In any case, I kept the seeds in water for three days and during these days it turned to the substrate. Before planting the seeds a substrate should be impregnated with solution two times lower concentration than is necessary for the cultivation. For the first experiment I used universal concentrated liquid fertilizer Vito for vegetables and flowers. The required proportions I dissolved it in water and poured substrate. After that I planted a seed in each mineral-wool cube. Germination takes place in living room with natural lightening. Once a day the room ventilated, I sprayed substrate with fertilized water. Also I follow up the green box to be always filled with water. On the 7th day the first result emerged.

On the 8th day first seedling germinated a little bit. In addition two more seeds germinated but unfortunately it is not visible on photo.

Now I am waiting until seedlings will grow up, so I can replant them to hydroponic setup and let them to grow under the artificial light.