"Sweet" and "Eversweet" supposedly produce fruit that is sweet even when underripe (...). They do not, however, look like traditional poms, with "Eversweet" having colorless or nearly colorless (but non-staining!) juice. Also not bright red on the outside.

I haven't tasted them but some who like poms consider these insipid.

Raintree suggests both of these for "cool-summer" climates. Planting them against a south-facing wall might help ("Sweet" is supposed to be a compact plant good for containers or espalier).

Seems to me you might call Raintree and see what they recommend. You might also check around and see if anyone in your general area actually grows poms. It might be a stretch.

Have never seen one fruit here (Portland), but those planted out in the landscape put out a nice bloom. For possible fruit, keep yours in a pot and put it in the hottest location after bloom.

All kinds of potted citrus are sold here laden with fruit right at the retail location. Never seen the same with a pom.

What size of pomegranate would please your mom? Unlikely you will end up with the store-bought fruit look from your potted plant.

Thanks for your responses. larry_gene, from what I've heard it'll be harder to have fruit from a potted pome plant.

So, I was actually leaning towards planting it in the most ideal area. The lady at the shop said after a year or two, it should bear fruit. But I don't think she fully understands Portland weather.

I'm leaning towards getting a lemon potted plant. Sounds like if you bring it in during the coldest months and leave it outside for the rest, you should see some lemon fruits.

OneGreenWorld is Portland. Maybe give them a call.
This might be of interest:
http://www.cloudforest.com/northwest/forum/20102395.html

A good alternative might be dwarf pomegranate nana. Produces quality edible fruit that are smaller in size than regular poms. Fruits here in Seattle, WA, so should definitely work for you down there.