The Gift Tree
The Gift Tree is a new plant introduced in the Ratboy's Nightmare update which is the most expensive gardening item- separate from the salamander eggs. It can be obtained, as of players are aware, only from Mr. Sims- who can be found directly outside Topple Town.
The gift tree seed can be purchased at random from Mr. Sims between 1,900,000 - 2,100,000 Gold. It always appears in the third slot:
The Gift Fruit sells for 700,000 each. They may be opened and are like a regular Otherworldly Gift, so opening them may not be the best option if you are wanting to profit off of them.