A single crack on one side usually doesn't do much harm.
Any advice on the crack
I'm glad I did not try to bend it back. So, it seems like time is usually the solution with all things bonsai.A single crack on one side usually doesn't do much harm. What I learned is that I have the reflex to wiggle it back trying to seal the crack. Then junipers tend to crack on the opposite side as well. Same happens with pines.
Super glue or wood glue can work, but it'll only close the wound and it doesn't help it heal. Waiting is the only option.
On my procumbens juniper it takes roughly two years to close/heal such a crack.
Thank youWelcome to Crazy!
Sorce
That is a fairly soft 4mm aluminum wire.Don't get high off your own supply.
Don't lick it.
Seriously though.....
Is the wire annealed? Soft?
You can almost see how the wrap is a little tighter than the 45-60degrees usually instructed at that point.
Of course this(tighter wrap) does happen after you bend sometimes, especially when the wire is a wee big or stiff, or wrapped against the spin and bend of the branch.
That tighter wrap creates the fulcrum and leverage the branch cracks against. No matter how it gets there.
Preventing that situation ...
Proper wire. Proper technique. Further planning.
Which is really just practice practice practice.
But the laws of physics reign always.
Always bend branches with as much hand and finger support as you can afford to get in there.
Pressing each side of the bend in towards the bend allows less stress to the outside of the bend.
"My hands the raffia".
It's more of a hand habit than conscious practice, but I tear branches off things(large trees and shrubs) all the time just to futz. This can greatly help train your sense of touch to the inner workings of branch fibers.
Time of year also has bearing. Hell, time of day according to when you water has bearing, etc etc etc. Say, if you watered and that broke, it may not have if you watered after bending.
Sorce
I couldn't hear what the tree was telling me
Glad I didn't mess with it too much afterYou will never learn unless you crack a few branches. Otherwise, as @Wires_Guy_wires said, as long as the break in the bark doesn't circumference the branch, it will probably heal. However as soon as you crack a branch, the key is too stop touching the branch. If you leave it alone, it will probably heal. If you continue to mess around with it, you will usually only make the break worse.
One other thing that can help is to wrap the injury site with wax grafting tape. It protects the site and provides a little structural support.