General Method Description

In addition to making money with Farming by growing herbs, you can earn some quick cash simply by picking berries from the four bush patches in the game. Each holds four berries, which will grow back in a couple of hours after you've picked them. This isn't supremely lucrative, but it's a nice bit of extra gold, and you get Farming XP as well. Note that you can get much more XP by also uprooting and replanting the bushes, but this takes more time and I've not included that activity here. Note that the bush patches are mostly in remote locations; for easier access I assume you have the Explorers' ring 3 and the ability to use rings of slaying. The Ardougne cloak you get from completing any part of the Ardougne achievement diary is also handy, as it teleports you right near the bush patch south of Ardougne.

At very high levels the wolpertinger familiar is of obvious benefit for this activity, as it doubles not only the number of berries you get, but the amount of XP as well!

Note that at high levels, you are probably better off harvesting white berries or poison ivy berries, but the process is the same for all of the various types, so plant whatever bushes will give you the most benefit in terms of gold or XP, whichever you consider a priority. (At mid levels you can only do jangerberries anyway.)