This is my personal favorite because it’s satisfying. Get a motion-activated sprinkler. Pigeons land, the sprinkler shoots water, and they freak out and fly away. It’s hilarious.
How to Get Rid of Pigeons From Your Garden, Balcony or Roof
They learn quickly that your garden = random water attacks. After a few days, they’ll avoid the entire area. It’s like reverse potty training for birds. Just make sure you remember the sprinkler is there before you go out to water your roses. I speak from wet, humiliating experience.