Resuki,
Years and years ago when I was a kid and volunteered at the Brooklyn Botanic Gardens they had one in the greenhouses that sprawled and kind of climbed other plants around it using tiny thorns. I don't believe they are supposed to be an upright plant.

Never tried to grow one of these myself, though the mentions of it in the houseplant books that I've seen all say that they get gangly as they get older. This is probably normal behavior.

Hi Resuki,

Sensitive plant (Mimosa pudica) is commonly called sensitive plant because the foliage closes and droops at the slightest touch. It is also sensitive to improper care. Bright indirect sunlight with some early or late day direct sun is good. Keep temps above 60 degrees. Keep the soil evenly moist, but not constantly wet; water when the surface of the soil feels dry.

It also should be pruned or pinched back regularly to encourage branching and to keep it full and to prevent legginess.

Spider mites can destroy it quickly. This is not a particularly hardy plant. It grows quickly from seed, but it loses its sensitivity and doesn't seem to last for more than a year or so. It is more of a novelty plant - kids love it. Good luck with yours.

BTW, The reason the leaves fold down when touched is so that the plant can protect itself from predators. As the fronds fold down, the sharp thorns are exposed, thereby discouraging animals from eating them. Whatever the physiological mechanism is, it is sensitive enough that it also closes the leaves in response to strong sun, wind and rain.

Will Creed, Indoor Landscaper

Thanks to everyone who posted. It's good to know that they aren't upright plants and this is normal. I'm pretty relieved about that.

I'll see about finding a little something for them to lean and climb on, that way they aren't falling all over my desk.

Again, thank you everyone.