Onion seed

Onion Seed is a members-only item on the OSRS Grand Exchange in the seeds category.

In-game examine text: "An onion seed - plant in an allotment."

It has a Grand Exchange buy limit of 600 every four hours, a high alchemy value of 1 gp, and item ID 5319.

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Onion Seed shows an active flip setup with a margin of +1 gp and 335,658 trades over the last 24 hours.

At the buy limit of 600 every four hours, max profit per cycle is about 600 gp — high margin with healthy liquidity.