During their discussion with Lily, Zane and the girls found that Lily had an exceptional ability. One which had applications to more than just fighting. Lily's skill, which she unlocked via her awakening, was the ability to manipulate plants of all kinds.
This was not only useful on the battlefield, where lily could cause the local flora to sporadically grow and constrict the movements of the undead. Something that allowed her to act as a control type wizard archetype. But she could also cause crops to rapidly grow to abnormal size and quantity.
What this essentially meant was that Lily had the ability to grow vast fields worth of crops within the vicinity of Gravestone. What would normally take an entire season to harvest and store could be done in a day with Lily's exceptional ability.