These two spectacular examples should make you visit the Strybing Arboretum/Horticultural Garden, at 9th and Lincoln, in the Inner Sunset district.
I shot these the other day (see date stamp on pic)…
See more at Picasa Web Albums, user: Jackbarry99.
Warning: you need proof of SF residency to get in for free. Otherwise: $7.00.
(the fee is under review and debate )