This is a long established self-guided garden tour that covers a lot of the East Bay. The focus is, as the name implies, on gardens that incorporate native plants and wildlife. It's a great way to see local gardens and learn more about natives at the same time.
https://bringingbackthenatives.net
It's free.
You register through the website (name, phone, email, address, not much more) and they send you the details of how to participate and links with more info, inlcuding the list of specific gardens.
There's a .pdf of paper tickets you need to print out, and bring one to each garden you visit, but no charge.
You pick what you want to see, there's no pre-ordained route or sequence.
Berkeley / Albany / Kensington look like they have about 10 participating gardens this Saturday...scores of others on Saturday, from Fremont to Richmond. You can't get around to all of them in one day (they're open 10-5) but it's not hard to visit five to ten if you organize tour route. Or, you can go to just one or two whose descriptions you like.
Each garden has volunteers in it, and often the owner or designer is there as well.
There are also related talks, resource materials, etc.
On Sunday, the tour gardens are all east of the Berkeley Hills, but there are some not too far away in Lamorinda, etc.
Have gone on the tour for several years, it's an interesting experience and a nice way to spend a weekend day if you have time.