Improve Shady Sands' Agriculture

Improve Shady Sands' Agriculture is an unmarked quest in Fallout.

Detailed walkthrough
Talk to Curtis, a farmer in the garden on the eastern edge of Shady Sands, and ask what he does.

If the Vault Dweller's Science skill is greater than or equal to 40%, they can inform Curtis that crop rotation is a better alternative to his current farming style. Curtis will then accept this idea as a sensible way to improve his agricultural method, and the Vault Dweller will receive 500 XP.

If the Vault Dweller uses the Tell Me About option, they can bypass the skill check by asking about crop rotation (typing anything appears to work; however there is no reputation bonus for completing the quest this way).

However, if the Vault Dweller's Science skill is less than 40%, the special dialogue option will not appear. If the skill requirement isn't met the first time, this quest cannot be completed, as there's only one opportunity to ask Curtis about farming.

Bugs
It is possible to be awarded 500 XP without actually repairing the irrigation system. When talking to Curtis, open and close the trade window. After exiting the conversation, 500 XP will be awarded.