I am curious about your setup? Are you limited only to a pump as the method of moving your water? Is there a pressure requirement for sprinkler system? Space requirements? Alot of farms use a water ram and/or a eductor with check valves to move water.
If you use a method to move your water uphill to a tank then you could use gravity and several different way to distribute your water. I do not full understand the problem on the forum. I was just thinking of all the things out there, that using a solar system to water a garden was overkill.
https://en.wikipedia.org/wiki/Hydraulic_ram
This guy build one with a 100 bucks and pumps water without electricity. This requires a hill.
This will require a moving medium. IE water or Air.
http://eductors.net/jet-pumps-for-gases/
This will have a limited static head.
Bell syphon
These probably will not solve your problem, but hopefully give you a few ideas.
