Lava Bonsai Plant is Withering?

Question:

My lava bonsai plant in withering up, is it too cold?

Hardiness Zone: 8b

Danielle from Mesa AZ

Answer:

Danielle,

I'm assuming you're referring to a bonsai plant that has its roots growing around a lava rock (root-over-rock style). Is it outdoors? If it is, it should be able to withstand frost. Indoor bonsai are generally frost-sensitive, and prefer 'average' warmth, but the optimal temperature for them can vary greatly according to specific plant type. Generally speaking, the warmth of a standard living room is good for the summer and the conditions you would find in unheated room in the winter serve as a useful guide.

When any type of bonsai plant starts to wilt, the usual cause is improper watering. Unfortunately, unlike houseplants, it's harder for bonsai plants to recover once they reach the point of wilting. Because these trees are kept in containers with minimal soil, calculating their water needs is one of the most challenging aspects of growing them. Most often, bonsai plants tend to be under-watered. You could also be witnessing something called physiological wilt. Instead of under-watering, physiological wilt is brought on by soil that is kept too wet, which keeps the root system from getting air. Daily watering is often necessary for bonsai. Give them water when the surface of their growing medium feels dry to the touch. Scratch the surface of the compost if you're not sure. Frequent misting to keep the air around the plant humid is also helpful.

Ellen