new allotment

[deb of the wych]

I have finally got an allotment 70ft by 35ft approx, of freshly rotovated soil but no fencing round.
I have planted my potatoes and onions in the bottom right hand corner
the short side faces sw
Any idea where to put my shed I have no one along the top short side or right hand side, entrance is through the bottom next to where I have planted my potatoes
any Ideas please
Deb