Grounding is half your fence. Remember that. It's half your fence. The majority of all electric fence problems stem from improper grounding.
If your earth is particularly hard or rocky, try burying the rods at an angle, getting the buried ends as deep as you can.
Also...
Rebar doesn't count -- it rusts, which affects conducivity.. And it's iron which isn't as conducive as a real copper or galvanized rod anyway.. Plus, unless you're using iron wire, you'll have corrosion issues from the metal mismatch. And unless you're using really long rebar and burying it deep enough to be in moist earth all the time, your fence will be spotty when the ground dries out.
T-posts don't count -- they're painted, for pete's sake. Maybe that's not much of an insulator, but you don't want any insulation on something that's meant to carry current. Not to mention, most are only buried maybe 18", which is way too shallow for a ground system..
As others have mentioned, a good way to bury a ground rod is to slowly work it into the ground, pouring water intermittantly as you go.. I pounded mine in, because I'd never heard of doing it the better, easier way...don't be like me. Pounding ground rods is NO FUN at all.
But do yourself a favor and find a way to get them in the ground. You won't regret it.
