I bought two terraria for Christmas presents, glass globes about 10-15cm (5") in diameter, with cork stoppers. They have a coleus, moss and another plant I don't recognise.
All the guidance I've seen, including the notes I got with them, assumes that a terrarium is sealed, but these have a hole through the cork, about 6mm (1/4") in diameter, obviously deliberate.
They look healthy and the soil is really dry, enough that transporting them by bike shook some dust up the sides. I gave each a few drops of water when I got them home, well spread out - literally a few drops, as I used an eye dropper to ensure I didn't get any part actually wet. And I'm keeping them in a bathroom for the time being
Because they're not sealed, they will exchange humidity with the room. So will they need some watering? If so, how much, or rather, how could we tell when they need it?
Closely related, I'll have to wrap them up on Friday morning, to be unwrapped on Christmas Day. This will mean about 3 days of complete darkness. Does that change anything? I would guess that they should be kept dry during that time, but might need a little water when they're back in the light.
