Terrarium Ficus.. need help (light, humidity)

[Disgruntled_ficus]

I have an 18"W x 18"L x 24"H terrarium I want to grow a ficus bonsai in.

Right now I have 46W of compact flourescent daylight (5000K) bulbs in a terrible reflector rated for a total of 3200 lumens - though im not confident that is all being directed at the plants given the reflector. I can add up to ~90W more of CFL if necessary though would prefer not to.

Humidity seems to be hovering around 70% but I can probably adjust that somewhat.

How much light is optimal? What kind of humidity is optimal? I want to grow a banyan style ficus. Right now I have a ficus benjamina 'midnight' and a variegated benjamina in there. I will probably remove one (probably the variegated) when space becomes an issue.

 

[Deleted member 18707]

What is important is not just the lumens of the bulb, but how much light reaches the surface of the leaves, and at what 'density' for lack of the proper word. A better comparison for you to do would be to get a cheap Lux meter (used in photography) and compare the lux reading the tree will get in your terrarium, and then go outside and check the lux in full sun. Full sun will most likely be well over 100k lux, compared to a fraction of that in your terrarium. The folks who grow ficus indoors successfully (Jerry Meislik comes to mind, as does "Redwood Ryan" on this site) probably use some fairly significant growing lights like T5 High Output fluorescent or High Pressure Sodium lighting. When I was growing trees indoors in Michigan I had 4x48 inch T5HO bulbs about 1 inch above the trees. Even with this setup, I was still only receiving less than half of the intensity of full sun at best, and only for the first few inches away from the light fixture. The intensity diminishes quite rapidly as you get farther from the light fixture.

Here's a good link from Jerry that explains growing ficus indoors.

In my personal experience, I had a really hard time balancing humidity with air movement when I tried growing in a terrarium. If you just have an enclosed terrarium with stagnant air, you may have problems with mold.

 

[Disgruntled_ficus]

What is important is not just the lumens of the bulb, but how much light reaches the surface of the leaves, and at what 'density' for lack of the proper word. A better comparison for you to do would be to get a cheap Lux meter (used in photography) and compare the lux reading the tree will get in your terrarium, and then go outside and check the lux in full sun. Full sun will most likely be well over 100k lux, compared to a fraction of that in your terrarium. The folks who grow ficus indoors successfully (Jerry Meislik comes to mind, as does "Redwood Ryan" on this site) probably use some fairly significant growing lights like T5 High Output fluorescent or High Pressure Sodium lighting. When I was growing trees indoors in Michigan I had 4x48 inch T5HO bulbs about 1 inch above the trees. Even with this setup, I was still only receiving less than half of the intensity of full sun at best, and only for the first few inches away from the light fixture. The intensity diminishes quite rapidly as you get farther from the light fixture.

Here's a good link from Jerry that explains growing ficus indoors.

In my personal experience, I had a really hard time balancing humidity with air movement when I tried growing in a terrarium. If you just have an enclosed terrarium with stagnant air, you may have problems with mold.

wow thanks. Good site. The good news is that my light fixture is only 18"W so most of the light is positioned above the plants. I think the reflector should help combat the inverse square rule. Looks like I definitely need MORE POWER though, haha. Ill add another 46W and pick up a lux meter. Good suggestion!

I have been looking at some terrarium boards - mostly the ones meant for keeping dart frogs. It looks like a lot of them are trying to maintain high humidity. They put small pc fans inside the tank on an AC adapter to combat the mold issues you are talking about. I dont have the fan yet but its in the mail. I think the air movement also helps with respiration/transpiration and all that via Ficks Law on boundary conditions.

Something like this... (not sure if this is actually a good suggestion or not)
http://www.amazon.com/dp/B00DCCJQ0S...TF8&colid=2QYLHCAU0QQGN&coliid=I102853ROGBIDO

edit: still looking for humidity information. All I can seem to find is anecdotal type information without any quantitative type info

 

[Deleted member 18707]

edit: still looking for humidity information. All I can seem to find is anecdotal type information without any quantitative type info

Think about where you might find a naturally occurring large ficus tree with a ton of aerial roots (banyan style), and consider what the weather is like in that location. A quick search might find a place like Miyako (Japan) where the average daily high humidity is between 84-94% year round. In other words, as humid as you can make it.

 

[Disgruntled_ficus]

Think about where you might find a naturally occurring large ficus tree with a ton of aerial roots (banyan style), and consider what the weather is like in that location. A quick search might find a place like Miyako (Japan) where the average daily high humidity is between 84-94% year round. In other words, as humid as you can make it.

Another great suggestion! Im actually amazed how high the humidity is there year round. Very interesting!

 

[Deleted member 18707]

Good luck. I did quite a bit of research on indoor ficus in the past, but never had great results. I found it to be a fair bit of work to try to create an artificial environment that a tree would thrive in, but with effort it can be done.

Another tree that I actually had some success with growing indoors was a portulacaria afra (aka dwarf or baby jade). Its a succulent, so requires much less water and humidity, but still a lot of light.

Regarding your terrarium, what I've seen some folks do is line the inside glass with foil or some reflective sheeting, or even just white paint, to reflect as much light as possible back to the plant.

 

[timetravel_0]

Lux and lumens are basically the same measure. Lux is lumens per square meter. It's like saying I can drive 6 hours on the freeway, or 360 miles on one tank of gas.

 

[Redwood Ryan]

I grew Ficus in terrarium/greenhouse setups for years. I had a great amount of success and my trees loved it. However, a lack of air circulation and rot began to take a toll. Ficus wood rots easily, so I moved away from those kind of setups. Now I just grow my trees under 900W LEDs with a fan to circulate air.

 

[Deleted member 18707]

Lux and lumens are basically the same measure. Lux is lumens per square meter. It's like saying I can drive 6 hours on the freeway, or 360 miles on one tank of gas.

The way I understand it, the important thing for the plant is the amount of light it receives per square meter of its foliage, and even beyond that, the cumulative (over time) amount of light (lumens) it receives per sq meter, which could be thought of as lux-hours.

I don't think the car / gas tank comparison is applicable.

 

[sorce]

Lux and lumens are basically the same measure. Lux is lumens per square meter. It's like saying I can drive 6 hours on the freeway, or 360 miles on one tank of gas.

For a timetraveler, you drive slow!

Speed of light?

foil or some reflective sheeting, or even just white paint

Foil is useless. Matte white paint is best.

I think the reflector should help combat the inverse square rule.

The rule applies to the reflector, which lowers the light, and then it applies again to the leaves.

I'd ditch the terrarium, unless you are going for a banyan, in which case, high humidity can almost replace watering.

Sorce