Best Ways To Get Seaweed Spores In OSRS

Seaweed spores are an essential item for Ironman players in Old School RuneScape, especially for those looking to farm Giant Seaweed on Fossil Island and turn it into valuable Crafting resources. These spores can be obtained in several reliable ways, all of which are accessible without high-level requirements, making them ideal for early and mid-game Ironmen. Whether you’re gathering them from underwater spawns, pickpocketing Master Farmers, killing creatures like Lobstrosities or Ammonite Crabs, or trading with Mermaids in the underwater area of Fossil Island, there are plenty of solid methods to build up a healthy supply. In this guide, we’ll break down the best ways to get Seaweed Spores and help you maximize your Crafting gains with ease.

#1: Underwater Spawns

One of the easiest and most passive ways to get Seaweed Spores is by collecting underwater spawns on Fossil Island. While diving in the shallow water section, 1 to 3 spores will occasionally appear on the ocean floor just for you—these spawns are account-specific, meaning no one else can take them. Although the exact respawn timer isn’t known, new spores seem to appear every few minutes, making it a convenient method to gather spores while AFK or skilling nearby. Many players take advantage of this by picking up fresh spores right after harvesting their Giant Seaweed, keeping their farming cycle going with minimal effort.

#2: Pickpocketing Master Farmers

If you prefer a more active and engaging method, pickpocketing Master Farmers is another way to get Seaweed Spores, though it comes with a low drop rate. Requiring 38 Thieving to start, your success rate improves as your level increases, but Seaweed Spores remain extremely rare—sitting at around a 1 in 2,200 chance (roughly 0.045%). While this might seem discouraging, the real value here is in the wide range of seeds you can collect during the process, including herbs, allotments, and tree seeds—making it a great option for Ironmen looking to build a strong farming stockpile. If you’re already grinding Thieving or need more seeds in general, this method can be worth it, offering a slow but steady chance at spores alongside useful loot and solid XP gains.

#3: Killing Enemies in Fossil Island

If you’re looking for a more combat-focused way to get Seaweed Spores, killing enemies on Fossil Island is a solid option. There are three monsters that drop spores, each with different drop rates and quantities: Ammonite Crabs drop 2 spores at a 1/128 chance (0.78%), Lobstrosities found underwater drop 5 spores at a 1/20 chance (5%), and Fossil Island Wyverns drop 12 spores at a 1/65 rate (1.54%). While the drop rates vary based on the monster’s difficulty, this method is perfect for players who want to train combat while stacking up spores along the way. Whether you’re AFK training on Ammonite Crabs or farming high-level loot from Wyverns, you might end up with a nice stash of Seaweed Spores without even trying—making it a great passive option for combat-focused Ironmen.

#4: Trading Mermaids Underwater

 
Another way to get Seaweed Spores is by trading with Mermaids in the underwater section of Fossil Island, though it’s a slower and more niche method. You’ll find Mairin’s Market inside a sunken ship northwest of the Giant Seaweed patches, just past the drift net fishing area. Don’t worry about drowning—there’s an air bubble inside to keep your oxygen up. The shop sells Seaweed Spores for 20 Mermaid’s Tears each, a unique currency earned through the Thieving and Agility activities found just south of the shop. While this method does provide decent XP in both skills, Mermaid’s Tears are slow to collect, making this the least efficient option purely for spores. If you’re already training in the area, it’s a nice bonus, but most players should treat Mermaid’s Tears as a reward for the XP grind rather than a direct means of farming Seaweed Spores—especially since they’re also needed for valuable items like the Merfolk Trident.