Posted: 01/04/2015 at 12:54
I have come to this thread very late but I hope advice is still valid. You have lots of good advice above but I would second Wintersong's suggestion about seriously considering water and electrics for the end of the garden.
Yes, a hose can be extended from the house to the veg patch but it is so much easier if you have a second tap next to where you actually need it (rolling and unrolling hosepipe several times a week gets very boring!)
If you site the tap carefully you might be able to hide it a little so you can leave a hosepipe permanently connected or you might be able to set up a small irrigation system (fairly cheap & quite fun to do) to make watering the veg very easy.
Putting in water to the end of the garden is relatively cheap & easy when you are completely remodelling it - it's much more disruptive when you've laid your new patio etc. And if you are digging a trench for water I would put an armoured electric cable down to the shed at the same time. Make the trench about 3' deep with sand at the bottom - plastic water pipe on the sand, then more sand. Then a foot of soil and then the armoured cable.
You are just making life easier if you decide you want a water feature / lighting / use electric power tools in the garden in a few years time. I thought twice about doing it in my garden when we were digging everything up but eventually decided to bite the bullet & pay my landscaper a bit extra to do it. I use the water every day in the growing season, keep tools charged in the shed, a radio plugged in & the heated propagator on the go. I can also use my shredder near my compost bins . I don't know why I ever thought I didn't really need to do it.