Sure he can. He can scoop up all the Martian soil he wants and take it into the habitat. There he can eat it, snort it, roll in it, sleep on it, anything he wants. He can try growing vegetables in it, or just scatter it around to feel more at home.
But don't stay up late worrying about it. We aren't going to Mars, and I rather doubt we are even going back to the moon. Presidents who want to do something 1) throw money at it and 2) set the deadline within their terms or very soon afterward so that enough money is spent by the time they leave office to make canceling it politically unpalatable.
All Bush really did was kick the ball down the road.
I have trying to figure out the real motive behind this announcement for a couple of days now, with no success.
The only thing I can think of is this is a way to funnel money to important electoral vote states. I don't know where the design work will be done, but I'll bet Bush does. California? Ohio? Florida?