I did some work on the cherry blossom event last night. You first have to gather cherry blossom seeds from wild herbs (Everywhere), dry thicket (Mediah) and desert herb (Presumably Mediah but I didn't see any). You have to gather with your barehands. I used about 100 energy last night and got three. Interestingly they were all from dry thickets. Don't worry about what level you are. Just head to Mediah. Stick to the roads and it's fine.
Once you have some seeds you need a farm to plant and grow them. Each seed takes two slots. You harvest unwithering cherry blossom petals from them. 10 gets you a pot for your house and 30 gets you a cosmetic earring. I've harvested two of my trees so far and gotten 26 petals so it's a very generous event.