Yes, soap is VERY bad for the little birds. We can usually get our feeders completely clean with just hot water and toothbrushes or other scrubbers that are reserved for hummingbird feeders only. We NEVER use those tools on anything but the bird feeders and we keep them where nothing else from the sink or cabinet can contaminate them.
Glad you like the picture. That little bird spent an afternoon on the Garlic Chives, taking nectar from the blooms and then resting right there between sips!