fluffy,

This is what I suggest. 300 ft is a long length to run a rough surfaced 3/4" line. The problem is that the garden house that long will have a high friction loss. Run a schedule 40 pvc 1" line which has a smooth interior surface and will provide a much greater flow rate because the friction loss is way less. Since you will have a filter for well water and a backflow preventer to keep water in the line between pump starts you would have plenty of friction loss just from those fittings. You can lay the pipe on the ground since it is temporary fix for a year. PVC pipe would be comparable with the cost of garden hose. Run one line to see if that provides enough water to your garden. Since you haven't told us what the flow rate and pressure the well pump produces, if one 1" pvc pipe isn't enough then just add a second pipe in parallel with the first. I don't think this will be necessary though. GL Aloha

You could get a drip kit online or from the local home ctr, probably $50, then 3 100' of spools of 1/2" drip tubing, probably $10 each.

If you use drip irrigation then 1/2" pipe is more than enough for 10 rows of 6 plants.

If you use 2GPH emitters that is about 120 GPH or 2GPM, 1/2" tubing should be able to handle that with o trouble, I think you could do up to 4-5GPM on it would no problems.

So for $80 you would be all set. Drip is the best way to irrigate your garden anyway IMO, I have had great success with it. And you could take some of it with you when you leave and reuse at your next place. Even if you just take the pressure reducer with you it might make sense, it is a small part and is probably the most expensive piece of the system