Some info Start in the spring! It's coming.
Plant something you will eat.
The time to ripen depends on the plant. Some grow all season long and bear fruit throughout. Some ripen in a certain amount of time and then wither away, and you have to keep planting more of that veggie if you want more throughout the season.
Materials and tools depends on what you will do. Container, in-ground, raised bed? Sounds like it might be in-ground or raised bed. You'll need to consider things like amending your current soil or getting all new and different soil to grow with.
I'm also concerned about the fact that no grass is growing after 2 years unless you mean that the most of the entire tree is still just sitting there in that spot, taking up space that prevents a large growth of grass, but still decaying away (and not just the trunk).