If I'm jumping ground poles in a competition, do I need to switch my crop every time I change directions?

no even when your jumping a coarse you won't have to change the crop hand.
No, you don't need to unless this helps you or your trainer advises it, but the judge will not be looking for it.
No you don't
Heya Taylor, you don't always need to change your crop but it helps the horse a lot if its in the right hand as you can help keep it balanced:)
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