The halloweeds

Dan promised he'd look after his siblings, but he hadn't bargained on his scientist parents dying on a jungle research trip. The children decamp to crumbling Daundelyon Hall. Horrible Aunt Grusilla reigns supreme, tending her mysterious graveyard garden. But why are Aunt Grusilla and her servants each missing a finger? What are the hungry 'Cabbages' in the greenhouse? As Dan struggles to solve the mystery he encounters one final question: what's the price of everlasting life?