Not only is Oakland home to a number of wineries and an awesome brewery, it's home to an organic tea producer, Numi Tea. Numi has a lovely tea garden on site, as well.
You might have seen some of their teas in stores. Probably only 5 or 6 varieties; 10 or 12 if it's a well-stocked store. But Numi has dozens a varieties of teas: green teas, black teas, oolong teas, pue-rh teas, white teas, herbal teas, and sold both in individual packets for convenience and loose-leaf for lower cost and less packaging. If you're like me, you'll probably be overwhelmed by the options. The good news is that Numi knows teas, and can give you pointers on selecting ones you'll like. You can also learn about tea, how and where it's grown, the different varieties and the health benefits.
In many parts of the world, drinking tea is part of everyday life; in others it can be a cultural experience unto itself. At Numi's tea garden, you can relax and take part in the experience of tea drinking. The tea garden (and Numi's warehouse and production facility) is in Jingletown (aka North Kennedy Tract) between 880 and Coast Guard Island. (It's also near Irish Monkey Cellars and Stage Left Cellars.) An area filled with warehouses and converted lofts next to a freeway doesn't sound very relaxing, but inside the tea garden it is.
pu-erh tea. I actually spent a summer in the Yunnan province of China where it originates, but I can't recall specifically having had it (in defense of my memory, it was 20+ years ago.) I relaxed, listened to the fountain, and read my book. After a short while, my tea was delivered. Hot water was poured over the dragon/frog thing (which is for luck, I think), some hot water poured into the tea cup to warm it, and the rest poured into a clay pot for the tea to steep. The tray also has a timer with 3 parts, for 3, 4 and 5 minutes. Four minutes was suggested for my tea, so I flipped the timer and continued reading. The whole process involves waiting, which once you get into it, can be very relaxing. I read, I glanced at the timer, I listened to the sound of the falling water. After the tea had steeped, I poured it through a filter into a glass pot, and from that poured myself a cup. The pu-erh tea I had was very tasty, and the whole experience quite lovely and relaxing. I sipped tea, read, and relaxed. I'm honestly not sure how long I was there.
Before I hopped on my bike to head to my next destination, I purchased some loose-leaf teas that I knew my wife and I would enjoy: some of the pu-erh I'd just had, some Rooibos (from South Africa), and some Honeybush (also from South Africa). If you're a regular tea drinker, or just looking for a relaxing experience in Oakland, I highly recommend checking out Numi Tea.