In a large pot such as a dutch oven or stockpot, heat olive oil over medium heat.
Add celery, onion, carrots, and potatoes.
Cook 5-7 minutes, until onions are translucent.
Add the garlic, oregano, turmeric, salt, and pepper and stir. Cook until just fragrant, 30 seconds.
Add the garbanzo beans, whole rosemary springs (these will be removed later), vegetable broth, lemon zest and lemon juice.
Turn heat to high and bring to a boil.
Once boiling, cover the pot, reduce heat to medium low and simmer 20-30 minutes, until potatoes are fork tender.
Remove rosemary sprigs.
Using a slotted spoon, remove approximated 3 cups of the chickpeas and potatoes, as well as 1 cup of liquid to a blender or food processor (it’s ok if some veggies get in there to a blender).
Pulse until smooth, then stir into soup and serve. (Alternatively you can use an immersion blender directly in the pot to break up some of the soup until you reach your desired consistency).
Serve hot.