What does "a bumper crop" mean in the sentence below? Thank you for you help :)
Actually there was some point in hanging about the van as it was being unloaded. What you did - if you were one of these juniors - was to follow back and forth from the storeroom the two men on overalls carrying the big cardboard boxes, asking them what was inside. "A lot of goodies, sweetheart," was the usual reply. Then if you kept asking: "But is it a bumper crop?" they'd sooner or later smile and say: "Oh, I'd say so, sweetheart. A real bumper crop, " bringing a thrilled cheer.This is the quote from the novel "Never Let Me Go" by Kazuo Ishiguro.