Do pomegranate trees grow in Seattle?

Yes.

These certain palm trees grow successfully in Seattle

1. Windmill Palm

2. the related "Waggie" or Miniature Chusan Palm

3. Mediterranean palm (both green and blue varieties)

4. Needle Palm

5. Chilean Wine Palm

6. the Pindo or "Jelly" palm

Seattle is in growing zone 8 (Maximum winter lows between 10°F and 20°F). The last time Seattle saw a single-digit Fahrenheit temperature was 9°F in the winter of 1990-91. The all-time record low is 0° in downtown Seattle on January 31, 1950, and even then near the water it was still 4° warmer.

Marginal palms grown with success in Seattle:

1. Blue Hespar Palm
2. Sabal species - but it doesn't usually get warm long enough for their preferred 90°F high temperatures
3. Mexican Fan Palm crossed with California Fan Palm - In cold winters keep copper fungicide handy.
4. Canary Island Date Palm -shelter from NE winds, and use copper fungicide after periods below 17°F
5. California Fan Palm - once per winter requires a liberal dose of copper fungicide, also repeated after any cold snap below 20° to prevent mold and crown rot.
6. Mexican Fan Palm - best chance is near Puget Sound (Pacific Ocean saltwater) where the ocean moderates any cold temperatures - shelter from NE winds and cover emerging growth when below 20°F. *This palm can only survive 12°F if the center spear is wrapped and copper fungicide is added bi-weekly until the last frost in March.

The summer in Seattle is perfect palm weather, because May through September is the dry season, with summer highs between 67° and 85°F.

Typically only one to five days in the 90s, and the all-time high is 103°F.

However, Sabal Palms in particular do not prefer the cool, dry, semi-arid summers and do better in much warmer temperatures.