One of my favorite spring rides is Mt. Hamilton Road, where you can enjoy great views of Santa Clara Valley and wildflowers. A 2013 calendar shows the flowers and some scenic rides.
Over my 32 years riding here I’ve seen great years for flowers and mediocre years. It’s generally better when there’s a lot of rain, but not always.
San Antonio Valley offers the best viewing on the east side of the mountain. It’s one of the more remote areas in the area, even though it’s a bike ride away. Enjoy.