Yes.
Its basically for decoration. Just get a bunch and make a nice garden!
Well you need to make something that looks like hole but, underground .
all you have to do is dig underground and deep in to the place you can make a hidden temple
In "Castlevania: Symphony of the Night," the switch to open the underground garden is located in the "Marble Gallery." You need to find the hidden switch on the right wall, which is not immediately visible. Interacting with it will reveal the entrance to the underground garden area. Make sure to explore thoroughly, as the switch can be easy to miss!
No.
Leather - From a cow Iron - Found underground Gold - Found underground Diamond - Found underground Chainmail - Can only be obtained through the 'give' command or on Too Many Items
You can place flowers on dirt blocks or make a garden out of them. In minecraft 1.4 (which is coming out in october or november) they'll have flower pots which will be really cool!
sometimes a bug in underground mineshafts but imposible to do by ureself. In minecraft 1.2.5
minecraft
About 3 blocks underground on minecraft
dig a hole
UNDERGROUND (that's my fav)