this is VERY good stuff! thank you diana! good to have you here! most helpful! :)

Just bumping this up to the top.
Diana

Notice the way water is added in a closed terrarium. Almost a teaspoon at a time, just around the individual plant, and judged adequate by the amount of condensation.
Diana

Okay, thanks Diana. I guess I will have to spend more time with it. Darn, I wanted to give it to him soon. But I'm sure you are right about this stuff so I will work slowly.

About the not turning the plants, can I ask why again? We are told to turn our plants that are outside of a terrarium a quarter turn every now and then to ensure symmetrical growth, why not ones inside a terrarium? If I don't turn some of my plants once every month or so, they will lean and I can't turn the whole terrarium since it also functions as my living room coffee table.

I was really thinking of landscaped terrariums when I wrote that. Certainly, if the plants are in pots there is no reason not to turn them as you mentioned. I was aiming at those people who hop their plants all over the house.
Diana

Bumping this up for ddot.
Diana

i picked up a couple of ecology books at my universitys library, and i am trying to build a terrarium that is either self sustaining, or close to it. I think it can be done atleast for a certain amount of time. Currently i only open my bottle gardens when they look like they need some interventions other then that i leave them alone. I have though of a couple of expirments, and i will post the results and maby some people here can use them.
Wes

Hi Diana, thanks for the info on the saran wrap, if I would have read your posting before building my terrarium, it would have been make in a better way. But this is my first attempt at terrariums and with your info in this thread, there's more on the way. Thanks for the step by step how to on terrariums. Ken

Bumping up for Spunky.
Diana

I started a closed terrarium about a month ago. It sits in the greenhouse here at work. I suppose it is not completely closed but it is a large bell jar with a 2" bottle neck opening at the top (about 2 and a half feet tall). I placed rocks on a base that I found for it, a large 14"ceramic plant tray, for a landscaping effect. I put large ugly, sturdy bricks in first, then the pretty rocks. Then I put the bell jar over the rocks with the plan of never taking it off. Water still ends up leaking slowly, but not alot, it still holds alot of moisture. Then I started putting media in using a funnel and a small spatula taped to a long skinny bamboo stick. First pebbles, then sand, then a potting soil. Then carefully placed the plants in with my long tools. I chose a fine fern, 4 species of moss, 1 liverwort (Marchantia), venus fly trap, 1 sundew, a lycopod (Sallengela) and a small log of lichen. I spray it with distilled water two times a week with a spray bottle. It looks great and all my plants are taking off!!

That sounds like a delightful project. The only thing I would be concerned about is the possibility of mold growing inside the bell, since the level of moisture is so high if water is seeping in. With such a closed situation there is no way for the moisture to escape and it might accumulate there. How do you have it lit? I hope you will put pictures in.
Diana

Bunping this up for beginners.
Diana

Bumping up for beginners.

bumping

Hi Diane,

This is wonderful information that I have been searching for. My son is a Cub Scout and one of his tasks require building a terrarium. We are going to work on a closed terrarium. Really my only question was what type of soil to use as I know that regular potting soil would sour and the amount of light. Your original post answered both for me. I have plenty of houseplants for him to take cuttings and experiment with, such as Fittonia and an assortment of ferns. I thought about growing some ferns from spores but I do not have any fresh spores available at the moment. Thank you so much for sharing your experience and knowledge with us.

Rebecca

is there any restrictions on certain kinds of plants/speacies that he can have in the terrarium, is it sup[osto be a certain kind of terrarium, like bottle, tank, etc?
Wes

Hi
Very well written..This should help a lot of people start the right way
Have you ever attempted a desert type setup?? For cactus or Lithops or succulents?? I've never had any luck with this type
Gary

The trouble with trying to put cacti or succulents in a totally enclosed space is that they require sun to flourish, and that will build up too much heat. If you leave the terrarium open, you really are just using it as a glass pot, and none of the closed terrarium rules apply.

Mr. Breeze: At the Brooklyn Botanic Garden they had quite an extensive collection of lithops growing on waist-high benches covered with what looked like small marble or limestone chunks. The benches were enclosed in wire fencing because people kept stealing the lithops. They had to make the screens finer and finer because people would even steal them thru the screen. In any event, the succulent books I have say to grow them in full sun (or slightly shaded if under glass) in a wide pan or large pot (with other succulents if desired). They do not do well in a small pot. In spring they need a very fine overhead misting daily, with slightly less in summer. Cool and dry in winter.
Diana

Diana
Thanks for the info on the lithops. I can see that you're a purist when it come to defining "terrarium"When this list first started we had a discussion on the various
enclosures.Terrarium,Vivarium,Aquarium, Paludarium.Doesn't seem to be a definition.To me,it's gardening within an enclosed space.
Living in S.Florida I have to keep my terrariums open or they turn into vegetable steamers!! lol
Gary

And here I was, hoping to clear up the mixed messages that a beginner might have, that you can plant a terrarium as I describe, which is self-sustaining, but that it can be partially open and be watered. Once you lose and add water you simply have a whole different set of circumstances which need to be handled in a different way. Water is heavy and compacts the media, which needs to be taken into account when planting in an open terrarium, etc. Having additional water availability changes the humidity and starts requiring air circulation, something unnecessary in a sealed system. I have no expertise in dealing with these situations and don't want anyone innocently mistaking what I suggest as being rules for a different system. (In Florida you might use a closed system to keep humidity OUT.)
Diana

What is the best/safest way to sterilize the inside of a container that will be sealed? I've seen diluted bleach and lysol as options ... how long would residual chemicals be present?

thanks

I would think that if you rinse it REALLY well, using distilled water for the final rinse(s), that you'd be okay. I'd go with the bleach.

Diana:
I'm soo thankful for your post, just now, I was going to ask few questions, which you answered, I wish I read this before I set up my terrarium and would of made it closed, but now, I leave about 1/2" open on the glass top for air circulation, (I also have a small waterfall in it, the ones you buy as a unit, not with a false bottom) but noticed some mold, I sprayed it but I will have to remove the top for few days to dry the soil and just mist very lightly (for that period)the moss and my mini orchids. My next one will be done following your instructions to the letter, I made a copy of them for my file.
Thanks again, excellent and simple to follow instructions!
Ana :)

I have a relatively new 20gal tropical terrarium with a clay pellet layer underneath the substrate for drainage reserve. I keep the glass top closed except for 1/8" for heat escape. My tropicals have looked great for two weeks but I cannot get the humidity above the 50-60% range. I have a variable speed internal terrarium fan for air circulation which lowered my humidity by less than 10%. I figured the air movement was worth the trade off. I have no condensation with minimal r/o water in the drainage layer. I just figure that I will keep misting a few times daily until the humidity keeps on increasing. I have not been adding water directly to the substrate around the plants since the substrate is slightly evenly moist. I am afraid to add water directly to fill the drainage layer because it is liable to keep my plants wet all the time without any time for slight drying.

Any humidity help or other comments would be appreciated.

I'm worried about using perlite and vermiculite because of all the cons on them, especially about the health issues related to perlite. Any take on this?

Great information, thank You, Diana!

Thanks Diane for sharing your experience with terrariums. I have tried doing terrariums many times and always failed at it. I'll have to give it one more try now.

Chris