Watermelon seed

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

In-game examine text: "A watermelon seed - plant in an allotment."

It has a Grand Exchange buy limit of 200 every four hours, a high alchemy value of 33 gp, and item ID 5321.

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Watermelon Seed shows an active flip setup with a margin of +78 gp and 123,470 trades over the last 24 hours.

At the buy limit of 200 every four hours, max profit per cycle is about 15.6k gp — high margin with healthy liquidity.