The Peppermint Willow is a fast growing small to medium evergreen tree, to 25' around here (potentially 35' plus) forming a wide spreading weeping habit, like a weeping willow perhaps. Very interesting look when in full bloom as the flowers borne along the stem seem to show off the long arching stems. The largest ones I have seen locally is on Cedar St. at the Kuumbwa.
Leaves are evergreen, simple, alternate, narrowly lanceolate, 4-5" long by about 1/2" wide. Often slightly curved or falcate shaped with neither a top or bottom. They are stout like many in the family and showing reddish new growth as well. They are know for having a very strong peppermint smell.
Fruit are small capsules, really small, arranged in a round 1/4" cluster.
Young stems show a strong zig-zag characteristic, hence the name flexuosa.
Bark is deeply furrowed.
The purple leaf cultivar 'Jervis Bay Afterdark' is much more popular than the species. I have never seen an older specimen that forms a shape like its species. They really grow much slower I suspect.
Misidentification: Without flowers, smell the foliage, look at the habit. The leaves resemble so many others in the family, Melaleucas and Callistemons.
Aptos:
1122 Toledo Dr. (seen in the top picture)
Santa Cruz:
Cedar St. in the parking lot of the Kuumbwa club
201 Chilverton (Morrissey west) is a nice one
1313 Escalona Dr - 5 After Dark in one yard