My answer is that you can migrate from ruby's safari game, or, like the last guy who answered you can try a million times to get it on honey trees.
you have a chance to get them when you use honey on honey trees.
You have to put honey on a tree and wait a certain time.
you cant catch heracross in firered, you have to trade it from ruby,sapphire,or emerald You CAN catch Heracross in the Sixth Sevii Island after beating the Elite Four.
you can probably find it on trees. or you could trade it over form diamond, platinum, heartgold, soulsilver, or RSE.
you put honey on a honey tree and wait 4 like a day then u might find a heracross. if you don't u can trade with ur friends or use the gts system thing.
Put honey on honey trees and there is a 5% chance of finding Heracross.
Yes. You can catch wild heracross on Route 12 in the grass.
You can catch him by headbutting trees.
You can catch heracrosses by headbutting trees. But in order to have a powerful heracross your going to have to do some training. sorry.
Heracross is in the Safari Zone. Use an Acro Bike to get across the poles (white lines) and go North. The areas there hold Heracross (they are rare and hard to catch so beware).
on route 6665
Slather Honey on the yellow trees. Heracross has a 4% chance of appearing. I recommend slathering Honey on every tree you see, waiting 6 1/2 hours, and checking all the trees you slathered Honey on. Changing the DS time settings will not work, as the game cartridge has its own clock, and will detect if you changed the time