How large are your seedlings? A few years to bloom seems a bit ambitious to me...possible, not probable. You can always put some stakes in the container and put a clear, plastic bag over the plant...allow some fresh air in. You could also get a larger saucer, fill will stones and water, then set the container on top of that...not in any water though. This will create a little micro-environment. It may be essentially a house plant, but this has many more requirements than an ordinary house plant. Cacao requires acidic soil that will drain quite well. They will take water more than a lot of plants but don't go crazy with this during winter. I would give it indirect lighting as bright as it will stand. Even though it is mainly an understory plant, the more light it can take, the better off it will be. If it is warm in the home, you should get some steady growth. If you fertilize during winter...growth flushes are pushing...then dilute it a bunch. During winter, you may get away with exposing it to more sun than you ever would during the summer months. Good luck! It's a cool plant.

I found growing Theobroma cacao indoors pretty easy. In the winter I use bottom heat to keep the roots warm. I cant help with any flowering advice. My tree is about 2 feet tall, the outer edges of the leaves will turn brown do to lack of humidity. I use a mix of coconut husk chips and peat. The root system is very delicate so I suggest get care when potting up. I use a sea weed extract for feeding, early morning light seems to work well.

Also if your seedling fails, Ebay sellers do sell fresh pods. I ordered one from South America and the germination rate was nearly 100%. Fresh seeds are very easy to clean and germinate in a few days.

In 2006 I bought a ripe pod from Costa Rica for $15.

I was able to germinate 15 (there were ~50 in the pod I got sick & some didn't get a chance,) (I set them in a container with a loose lid with about a 1/4" of water in it,) all of which sprouted. 2 of them took over 6 weeks to sprout, the rest sprouted within a couple weeks. I put them in 2l plastic bottles with the tops chopped off. holes were made in the lowest points in the base. A sheet of cardboard was placed then a layer of marble (for calcium)chips, a layer of peat and the rest was filled with composted cow manure--unmixed (T. cacao likes very rich soil, lots of water and good drainage.

In the first 2 years I had them shuffling around underfoot and they got rather neglected.

They spent 3 months in a room with limited lighting and temperatures in the 45-50F range--with occasional dry periods.

I lost 3 trees during this period, all from dehydrating. One almost made it back, but had too little light I believe.

Finally I built a cabinet out of a 2'x4'x6' shelving unit--lining the outside with aluminized bubble wrap (used for heating ducts & radiant barriers,) the bottom with plastic sheet with a concrete mixing bucket holding a couple inches of pea gravel.

The inside of the box was lined with window film to retain moisture. Across the top of the box were suspended 4x2-tube 48" fluorescents on a timer. The bubble wrap across the front was velcroed at the corners--eventually the cats figured out a couple ways to break in, and I decided that they weren't doing damage.

The temperature over the winter fluctuated from around 80 when I had a heat lamp to gusts of 30F outside air.

I generally watered once a week, but occasionally manged to forget and things would begin dying--while the dried leaves always drop, the trees themselves survived this treatment.

Nearly 5, they may flower this year--but most of them will be in the local Wisconsin Stout Polytechnic University in their new rooftop greenhouse. At 6' tall they are more than I want to deal with as it was just to have some 'because' I will keep the two runts, which even now are only about 30".

Things I learned:

I believe that they are tough enough, especially after age 2, so that they can easily be grown inside provided that you can provide a humid, well drained environment...I'd run a pump and suck the water through a filter and regularly pump water into the pots. Keep their feet dry. Ideally I think they should be misted and kept above 65F, but they will tolerate lower temperatures to at least some extent.

The number one problem I had was finding deep tall containers--they are a tap root tree, and since I've not re-potted any of them, I don't have an idea of how the cramped root behaved. They're 6' trees growing in less than 750ml of manure which is 5 years old.

(T. cacao ideally likes 100F/100% humidity, bright, indirect sunlight. The plant dies if dried out at any stage of it's life, the seeds die rapidly if the temperature goes below 49F. High levels of compost and water--but dry feet. It has a deep taproot.)