Best Ways To Get Seaweed Spores (OSRS Ironman)

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Seaweed Spores are a seed obtained from various activities in Fossil Island, or by pickpocketing Master Farmers anywhere in the overworld.

They’re used to grow Giant Seaweed in the Underwater section of Fossil Island through the Farming skill, which can be later converted into Crafting supplies. This is highly popular among Ironmen because of its convenience & low level requirements.

Ironmen have a few good options to obtain Seaweed Spores, all listed below:

  • Picking Underwater Spawns on Fossil Island
  • Pickpocketing Master Farmers
  • Killing Lobstrosities, Ammonite Crabs, or Fossil Island Wyverns
  • Trading Mermaids underwater on Fossil Island

So let’s look into each option in more detail.


Option 1: Underwater Spawns

A Seaweed Spore Spawns / OSRS

Pictured above: a seaweed spore spawns

While diving in shallow water, 1-3 Spores may randomly spawn anywhere on the floor.

While the precise timing is unknown, this seems to happen every couple of minutes.

Spores that spawn this way in your account are only visible to you and may not be taken by other players. So no need to rush!

If you’re AFK or doing a bank skill just above, this can be a great way to stock/replace your Spores – since it doesn’t take any effort, and is rather quick.

Additionally, it’s common for players to wait for a spawn during their Giant Seaweed runs, to plant them in the patches they’ve just harvested.


Option 2: Pickpocketing Master Farmers

Pickpocketing a Master Farmer in the Farming Guild / OSRS

If you’d rather use a more dynamic method, you may be interested in pickpocketing Master Farmers.

These require a Thieving level of 38, with your success rate increasing with higher levels.

But either way, Seaweed Spores are very rare. You’ll be getting them generally at a chance of 1/2200 (0.045%).

Some players might feel discouraged from attempting this method, since the fail rate can also be frustrating and result in even more time invested.

On the other hand, Master Farmers can yield a large variety of useful seeds for Ironmen, including herbs, trees, and allotments!

So if you have yet to stock up on seeds, Master Farmers may be worth your while.

This way you can collect Seaweed Spores along with other useful loot & decent Thieving XP rates.


Option 3: Killing Enemies in Fossil Island

Fighting a Fossil Island Wyvern / Old School RuneScape

If you’d rather go for a combat-oriented alternative, we’ve got good news!

Seaweed spores can be obtained from killing three different types of enemies, all scattered around Fossil Island:

  • Ammonite Crabs – 2 Spores @ 1/128 chance (0.78%)
  • Lobstrosities (Underwater) – 5 Spores @ 1/20 chance (5%)
  • Fossil Island Wyverns – 12 Spores @ 1/65 chance (1.54%)

The drop quantities and rates are quite varied, depending on the monster’s combat level.

But these can prove to be a quick yet most intensive alternative, for those that would rather beat some monsters up.

You’ll also likely you’ll be able to stock up on Spores if you just prefer to grind your Combat skill XP with Ammonite Crabs, or while farming a rare drop at Wyverns.

If that’s the case then you may be stocked up already without even realizing it!


Option 4: Trading Mermaids Underwater

Mairin’s Market Underwater on Fossil Island / OSRS

This last option to obtain Seaweed Spores is by trading with Mermaids in the underwater section of Fossil Island.

These Mermaids stock some very unique items, one of which is Seaweed Spores.

Mairin’s Market is located in the sunken ship northwest of the Giant Seaweed patches, just west of the drift net fishing area.

If you need it, there’s an air bubble inside – so you needn’t worry about your oxygen level!

This shop operates with Mermaid’s Tears as currency.

You can obtain these by participating in the Thieving/Agility activities in the same Underwater section, just south of the shop.

Each Seaweed Spore goes for 20 Mermaid’s Tears.

Gathering Mermaid’s Tears Underwater / OSRS

This method is the least recommended due to the rarity of Mermaid’s Tears – which means you’ll be spending a more time to get your Spores.

Going after Mermaid Tears does result in decent Thieving and Agility XP rates.

But we recommend considering these Tears a byproduct of the XP, and not the main objective – that way they can be used for other items, such as the Merfolk Trident.

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Born in Argentina in '97, Been gaming since I was a kid, and met a lot of worlds I've grown to love. Big fan of JRPG's, Metroidvanias, and planning ahead. I'm a barefooter, a competitive Smash Bros player, and a bit too stubborn at times!