51cg

Hi everyone,

I’ve tried to research this a bit online without much success, so I thought I would ask here to see what folks with more experience say. Most of what I have found about pruning acacia trees is focused on landscape tree outdoors. I have a large bullhorn acacia (Vachellia cornigera) that is growing indoors under good grow lights. I just kind of let it do its thing and trim branches back when it starts to shade out the other plants under the light. Id like to keep it as a bonsai, but it’s been growing for years without much direction. The result is basically very long leader that grows straight up, which I know is pretty common for acacia. The thing grows like a weed during the growing season.

My question is would it be harmful to cut it down to the main trunk to get branching to be more compact? There is no foliage lower on the tree. If essentially cutting off all the foliage is okay, when is the best time to hard prune a tropical tree that is grown indoors?

Ive attached some pictures below to show what I mean. Sorry they arent very clear.

Acaccia are a bit of an odd group. THey are often pruned in the wild (hence the thorns) and deal with it well.
I still personally would opt for big cut when it is dormant, just before you bring it into growing season mode.

Maybe cut the leafless wood out first and shorten the main leader by half

"Instead of making one drastic cut, use a gradual approach over several months:Locate Hidden Buds: Closely inspect the branch closer to the trunk. Look for tiny bumps, nodes, or green spots. These are latent buds.Make a Conservative Cut: Cut the branch back partially, ensuring you leave at least 3 to 4 healthy leaves at the very end of the remaining branch. Do not cut back to bare wood.Wait for Backbudding: Place the tree in a sunny location and maintain normal care. Wait for the latent buds closer to the trunk to pop open and grow into new, leafy shoots.Final Cut: Once those new inner shoots have grown several leaves of their own, you can safely cut off the original outer tip. The new inner leaves will now take over as the sap drawer."

After looking for a long time for this anwser, I finally found this piece of advice. Hope this helps anyone with the same question!