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Harvesting Agave for Tequila. I n the past, agave were harvested when the jimadors decided they were ripe enough. This was generally done when the agaves were from eight to ten years old. Jimadors knew, from generations of experience, when the agave was ripest, when it was rich with sugars and ready for harvesting.
I collect my Yucca and agave seeds when they are well dried and the seed pods are splitting. I read somewhere that the viability does decrease with age, but I have still had luck with three year old seed, probably just not as much luck. Anytime anyone has Yucca or agave seed , I am always interested.