Buy OSRS Gout tuber
The gout tuber is a rare item in Old School RuneScape. Players get it from the Tai Bwo Wannai Cleanup minigame on Karamja. It is both a seed and a food.
The gout tuber is needed for the medium Karamja Diary. Players trade Safta Doc a gout tuber, three specific unnoted gems, and trading sticks to get a gem machete.
You can plant a gout tuber in a herb patch to grow goutweed. This needs level 29 Farming and the quest Eadgar's Ruse. It grows in 80 minutes and gives 3 or more goutweed. Goutweed can be traded to Sanfew in Taverley for a random herb each.
You can also eat a gout tuber. It heals 12 Hitpoints and restores 50 run energy.
Getting a gout tuber on your own is slow. It is a rare drop while hacking jungle, and even a focused player can expect to spend close to 1 hour and 15 minutes to find one. Buying a gout tuber skips that grind, so you can move straight to your diary task or your Farming patch.