Zone Most of the species in the Gratis Garden Trees program are adapted to all of the climate zones in our community – from the highlands (Zone 21) to the inland foothills, canyons, and mesas (Zone 22 in Brentwood, Zone 23 in Pacific Palisades) to the coastal canyon bottoms and back dunes (Zone 24) – but there are a few that would fail to thrive in particular atmospheric moisture levels and/or temperatures, so they should be avoided in some of these locations: