where is the Hanami emoji? add it now.

You can submit it, but I can pretty much say you'll be wasting your time. From the submission rules:

1. Faulty comparison: Are proposals being justified primarily by being similar to (or more important than) existing emoji?An existing emoji’s existence does not justify proposals for emoji like them.
2. Examples:
   1. Four different mailboxes {📫📪📬📭} do not justify adding a “more important than a mailbox” emoji.
   2. 🆕 new button does not justify adding an emoji for “OLD,” or an emoji for “NEU” (German). The same is true of ideographic emoji, such as 🈯 Japanese “reserved” button.
   3. The emoji {🐶🐕} do not justify additional front versus full-body views of the same animal.
   4. The emoji {🐕🐩} or {🐪🐫} do not justify adding different varieties of the same kind of animal.
   5. The Tokyo Tower🗼(a specific building) does not justify adding the Eiffel Tower.

Your request would fall under this reason for denial. It's just a tree. And there are already several trees to choose from.

Emoji are determined by the Unicode consortium, Unicode.org.

You are not addressing Apple here.