Since the start of this hobby I tried to make some kind of acceptable living conditions for indoor bonsai’s. Though from start I haven’t had more than 1 tree filling the would-be shelf I anyway started creating one.

Setup

The present shelf is made of Ikea Detolf glass-door cabinet.

Into upper corners of each shelf I set spot LED lamps of different producers: Kanlux, EcoEnergy, OSRAM and Neolux. For simplicity reasons I used GU10 connectable directly to the mains, ~220V. Each lamp is 5-6W (depending on the model), having beam angle of 25, 36 and 120 degrees. The latter one is having way too wide beam angle but as the idea of having this shelf was also to replace the main indirect floor lamp in the living room I accepted them for the first version. When they break I will replace them with more narrow beam. Each lamp generates 350-430 lm of light. Out 4 lights on each shelf 3 are of cold white light (6000K) and 1 is warm white light (2800K). Though warm white generates more leggy growth I considered to add some red part of the lights to the plants as the 6000K lights generate less of it. The time will show if that was correct.

The top shelf has an extra spot LED light on the very top. The 3 cm hole on the top is original made there for Ikea LED in-cupboard lighting. I didn’t install the original as it is not strong enough for my needs so I left it opened for humidity control reasons.

All LED lights are connected together via a timer which sets 15h of light and 9h of darkness during the night.

After some tests and need to control humidity more I added window rubber seals around the doors leaving only the bottom part unsealed. The fresh air comes in from the bottom and travels due to the heating of the inside lights upwards and gets out of the top hole.

All the cables are not yet extremely nicely put but in time I will manage that too.

On the top of the shelf I installed 2 x 24W fluorescent lamps, 2800K, to give more indirect light into the room controllable by a different switch.

Experiences



Though amount of light is somewhat questionable (still waiting for proper measurement) I consider it quite enough. At the moment it looks the trees get around 30.000 lux each. For ficus it is enough for more than just survival. For other the time will tell.
To control temperature and humidity I open/close the top hole with a piece of plastic from above (inside white plexiglass). If completely opened the humidity goes out much faster than I need. Half closing it works at the moment well.
I installed small hygro-thermo meters to see both values on each shelf. It shows to be a good idea as due to the hot air trip upwards the values are different on each shelf. This way allows use of different shelf for plant with different needs.
For the room air conditions of 20 degrees C and 40% of relative air humidity I get:

  • temperature, lowest shelf = 22 C  and highest shelf = 29 C
  • humidity, lowest shelf = 40-50%, highest shelf = 70-95%
The higher humidity values are when plants are just watered and lower ones are a little bit before the next watering. Of course the values differ if the doors are opened just before measuring. The humidity didn’t tend to go too close to 100% and make steaming effect unless the top hole is completely closed.



The temperature seems to stay around 29 C max for which I am very happy about as I consider it right for most of the plants. It will slightly drop during the winter when the rooms temperature drops slightly especially over night.


Otherwise the lights are working fine also for living room lighting needs. At least my wife doesn’t consider it bad. Perhaps the setup is not WAF=1 but around 0.9 but it is close enough…for now 🙂

UPDATE:
I got the light meter and did proper measurements. Under the lights of 25-36 (no much difference between the 2 on the short distance) degrees beam angle the strength is 80-100 klux (kilo lux, 1000 lux) couple of centimetres from them for an example on the top shelf where the plants are cramped for now but then they are very near to one of the lights.
The spot light with 120 degree beam angle the strength is substantially lower, somewhere around 20-30 klux.
When measured in the middle of all lights like in the second shelf where ficus is located the light is around 50 klux. That is in the middle. Considering the plant is standing on that spot and branches are wider away of the center spot the surface of the branches are nearer the lights and therefore receive around 70 klux, on the side where the spot lights are 25-36 degrees.

I am turning them every time I water so all sides get sometimes stronger sometimes lower strength of light. As mentioned, when these 120 degree lamps break I will replace them with narrower angle this increasing the average light strength.


So, the present strength of 50-70 klux compared with the sun of 100 klux is pretty well. Not for the most sun hungry plants but for the rest should be OK.


All together, I am satisfied with the light strength. Though not covering completely the full surface of the plant they in my opinion satisfy them and they are developing quite well. Ficus, normally happy with lower strengths is growing like crazy. The new Carmona also started giving new growth all over the place and lots of flowers.

Below are more photos from the present set.

 

Only the second shelf: