With Multiboxing you can harvest the new Seed without Replanting them. That work because as long as the Home Instance Creater dont Harvest them the new Plants dont go away. So with more than 1 Acount and Multiboxing you just need to go into your Home Instance, only Harvest the Plants with the Second Charakter and send them viva post to the main charaktar. Aslong as you dont Harvest them with the Instance Creator the Plants dont vanish at the Moment. That is an Exploit because all other notes dont have significant material investment requirements to make them harvestable or put out highly restricted materials that cant be farmed anywhere else.