Perhaps the best way to shoot close-ups is to use a single camera on a slide bar and to precisely measure and create the correct stereo base.
But that can be a tediuos process, especially when wind and other factors prevent perfect fusion.
My vertical-format SDM twin camera rig makes shooting a bit easier, although the stereo base is fixed, preventing fine-tuning.
The front door of my house is graced by springtime flowers.
Marshall