Greens on floating raft - failure

My last experiment also regretfully failed. After being replanted into hydroponic system plants significantly withered.

Seeking for a reason of my failures I checked pH level of fertilizing solution. Test showed value of about 8. I was quite surprised with such a fast rise of pH level of solution. By adding some vinegar I adjusted acidity of solution back to 6. But when I checked pH level next morning it was 8 again. I repeated procedure of adding vinegar next 2 days in a row and both times next morning pH level was 8. I decided to check pH level of clay to find out if it is the cause of my problems. I put a handful of clay into 1 l of water for half a day and checked it's pH afterwards. Result of this test was 8 although in the beginning it was about 6. It became clear that clay was guilty in my previous failures also. I decided to use more neutral substrate for my following experiments. Most probably it will be coco-coir.

Greens on floating raft under LED-light

Finally I've received my order consisting of LED bulb. This is how LED bulb with red and blue diodes and 15W power looks like:

Wasting no time I prepared my self-made floating raft hydroponic system and filled it with fertilizing solution same amount and concentration as I described in my previous post. For this experiment I used basil and lettuce plants which grew in turf on my window sill.

After washing roots carefully I replanted basil and lettuce plants into pots filled with clay and installed them into hydroponic setup. After that I hanged LED-bulb above plants and switched it on.

Now I'll watch how my plants will develop. I hope that this experiment will be successful!

Lettuce on floating raft

I didn't write for a while because of massive amount of work and health problems. Therefore this time I'll briefly describe my experiment of growing lettuce hydroponically in floating raft system, also its results and conclusions.
3 days after planting lettuce seeds germinated. At this point I realized my first mistake. Every "How-to germinate lettuce seeds" manual I've read advised to water turf first and plant seeds afterwards. In a hurry I did it in wrong sequence - at first planted seeds and watered them afterwards. As a result in few cells I washed seeds too deep and they didn't germinate, in few other cells they moved and germinated too close to a wall of a cell.

I took a cover off my mini-greenhouse and left my lettuce sprouts to grow on a window sill under sunlight. They grew well. This is how they looked after a week:

In about two weeks lettuce sprouts grew big enough to be replanted into my hydroponic setup.

I put my floating raft hydroponic system near a window, turned its aerator on and filled tank with solution. I used Vito 1 liquid fertilizer dissolved in water in recommended proportions for this experiment. I had to adjust acidity of solution by adding a bit of vinegar to lower pH level above 6.

After filling approximately 20 l of solution into a tank I put a foam rubber raft on a surface.

Then I started replanting lettuce sprouts to clay. I took them very carefully out of turf and washed roots under running water.

Holding lettuce sprout above a pot so that its root hangs inside I carefully filled clay.

At this step I realized my second mistake. Clay granules were too big for such a little sprout. It was very hard to make lettuce sprout maintain vertical position. Next time I will use smaller granules.
As I finished replanting pots with lettuce sprouts were installed into floating raft hydroponic system.

Next weeks brought me problems. First of all - direct sunlight reached my sprouts through a window just till noon. Another half of a day they received reflected light only. Second problem started day after I replanted sprouts into clay. Sky became very cloudy and long raining period started. The sun was very rare guest whole next month and sprouts desperately lacked sunlight. In a week they grew just a tiny bit.

Whole next month was cloudy and rainy. This is how my lettuce looked like by the end of it:

One plant died and was thrown out. Others were very weak. Leafs were very pale, thin and brittle. Instead of growing upwards they just lied on raft.
I concluded that my experiment failed. It became obvious for me that I never should rely on natural factors while growing in artificial circumstances. Next experiments are pointless without artificial light. I ordered led-lamp with 36 blue and 90 red diodes and 15W overall power. Next experiment will take place after I receive my order. I believe that light will bring me success.

DIY "floating raft" hydroponic setup

The name of this system perfectly fits its essence - plants are planted into holes on a raft which is floating on surface of fertilized solution. Commercial growers are using big sized rafts floating in big sized beds.
I decided to build small and compact hydroponic setup because my main goal right now isn't business but experience. To make it happen I had to find following materials:

- Plastic container from household goods store - 4 €

- Aquarium aerator, aero-rock and plastic air-conduit from zoo-shop - 9,5 €

- Sheet of foam rubber from construction goods store - 1 €

- Clay from gardening goods store - 1 € for 1,5 l

Planting pots. I didn't find anything suitable in Jelgava. So I made pots myself by cutting holes in plastic cups which I found at home.
Building small floating raft hydroponic setup took following steps:
- I put plastic container on foam rubber and drew its shape.

- Cut out the raft with necessary shape. In manuals it's usually recommended to use electric fretsaw for this purpose. I don't have one so I used a knife instead.

- Put cups on the raft and drew a circle around each.

- Cut holes in the raft with 2 mm inside offset so that cups fit tight and don't fall out. It's recommended to use milling cutter for this purpose. It cuts holes accurately and fast. I don't have such a tool so again I used a knife instead.

- Put a cup into container and drew a fat mark above. It will be hidden in filled setup. When level of fertilized solution will become too low this mark will appear. It will tell me that it's time to add more fertilized solution.

- Put aero-rock into container and connected it to aerator outside with air-conduit. Purpose of this step is to add oxygen into fertilized solution when this setup will be filled and plugged in.

- And finally I put foam rubber raft with cups into container.

So building this hydroponic setup costed me less than 15 €. Theoretically after filling this setup with fertilized solution and turning aerator on I can plant something into it. Only moist-soil loving plants (basil, lettuce e.t.c.) should be planted into floating raft hydroponic systems. In my next posts I will describe how successful this hydroponic setup was.

Lettuce germination

After long break I returned to experiments with hydroponics. This time I am growing lettuce. Like basil lettuce is easy to grow and not demanding. For me as a beginner it is quite important option. I want to grow 3 different breeds of lettuce at the same time - 'Pirat', 'Salad Bowl' and 'May Queen'.

For this purpose I've purchased mini-greenhouse.

After filling plastic cells with turf I planted few seeds in each.

http://hydroponeast.com is advising to water substrate well and feed seeds with low concentration fertilizer from the beginning. I mixed solution with half of recommended concentration. I used Vito 1 liquid fertilizer for this purpose. Recommended pH level for lettuce is 2,8-6,1. PH test of my solution in substrate showed approximately 5,5 which I considered to be good.
After watering substrate I put cells into mini-greenhouse and left it in a room with good air circulation and temperature about 18 degrees by Celsius.

In theory sprouts should germinate in nearest 3 days. After that they're supposed to be taken out of mini-greenhouse and put under good light for one week. When sprouts grow bigger I will replant them into floating raft system. I'm going to describe how it's built in my next post.

Replanting basil

I didn't update my blog for a while because of having a lot of urgent work to do. Meanwhile my basil plant has experienced some changes and transformations. I'd like to describe all of them in one post.
Plant has grown enough to be replanted to hydroponic setup. Zachary Jones advised me to replant it after first set of true leaves. Unfortunately I've skipped first leaves because extreme lack of time - I had to finish and defend my diploma-work. At the moment of replanting there were already few sets of leaves on the plant.

Besides, seedling which sprouted on clay also grew a bit taller. I carefully took basil plant out of its cup with turf on its roots.

I made deepening in clay inside my hydroponic setup and put my basil plant inside. After that my plant constantly received full dosage of fertilizer. Besides roots constantly received oxygen from aerator.

For first 3 days there were no changes. I started thinking that replanting was bad idea. But apparently this time was necessary for adaptation. Starting from day 4 basil started growing very fast. This is how it looked approximately a week after replanting:

Unfortunately the seedling which sprouted on clay died. I think - because of overflow. Hereafter I filled hydroponic setup with fertilizer on regular basis and watered leaves with dispenser. After 3 weeks basil grew very big.

It's leaves are sweet. Added to a salad or porridge they added wonderful aroma to a meal. I never noticed same quality with basil from a store.
I decided also to describe my observations about my first hydroponic setup. Its undeniable advantage is easiness. Such a setup is very easy to build and also to use. But on other hand it has also huge disadvantages. This is open type setup. As a result fertilizer evaporates very quickly. In one month I spent about 5 l of solution. In my opinion it is quite big amount. Second disadvantage is size of setup - about 2-3 plants can be planted only. Enlarging it would mean also increasing expenses on substrate (in this particular case - clay).

Basil

Surprisingly two of ten seeds which I planted straight into clay finally sprouted.

I added 50% solution to water in the setup and put it under sunlight. It is interesting how growing will develop.
Besides basil which I've planted in paper coffee-cup has grown much bigger.

I think that quite soon I will be able to replant it into my hydroponic setup.

The first basil sprout

One week have passed since I planted basil seeds. One of them finally sprouted.

This is sweet basil 'Holy'. Unfortunately other seeds died. I put a paper-cup with seedling to window sill to receive sunlight. Since now I'll have to water seedling 3 times per week and feed standard nutrient solution 2 times per week (info from http://hydroponeast.com website)
Besides Виталий Марин gave me an advice to try planting seeds directly to ceramsite. He also showed me a picture where this method gave him results. I decided to give it a try. I filled my hydroponic setup with water to which I added a bit of vinegar to keep pH level at about 6. Then I poured about 10 seeds into it, turned aerator on and covered setup with folded cheesecloth to keep seeds in darkness. Hope that this one will succeed.

2nd experiment - basil germination

This time following Zachary Jones advice I decided to germinate a plant which is easier to grow hydroponically - basil. Besides I decided to germinate seeds on turf. I was in need of special baskets for this purpose. I've seen them on foreign websites but didn't find anything alike in my city. I made decision to make  baskets by myself by cutting holes in paper coffee cups.

I learned from mistakes of my first experiment that pH level of substrate should be checked before planting seeds. Test showed pH level about 6 which is optimal for basil.

After filling cups with turf I planted seeds about 1 cm deep. I planted sweet basil Holy in 2 cups and Thai in another two.

I put cups into container and watered them well with warm water. In materials on growing basil which I have read it was mentioned that few days after planting seeds fertilizer shouldn't be used. Recommended water temperature - 22-24°С.

I placed container with cups into self-made growhouse described in one of my earlier posts. Recommended temperature for basil germination is 22-24°С but recommended air humidity 93-95%. Thermometer inside growhouse shows 22°С. I am worried about air humidity. Right now I don't have any tools to check it or keep at constant level. I decided to use a bottle with sprayer. I will spray water inside my growhouse few times every day. Now I have to wait few days for my seeds to germinate. Then I will move seedlings to window sill to continue growing under sunlight.

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.