Jonathan Harker first makes mention of the boxes while being held prisoner at Castle Dracula; he witnesses Dracula's human servants loading 50 boxes with earth from the castle. Later, when the ship "Demeter" runs aground in England, the authorities find the boxes onboard. They are destined for Carfax Abbey, Dracula's new home, as well as other locations throughout London. Since the authorities suspect no foul play, they deliver the boxes to their appointed destination.
Count Dracula transports the boxes of earth so he may sleep in them, as Harker discovers in Castle Dracula. Opening one of the boxes, he finds the Count "either dead or asleep" inside. According to Van Helsing, Dracula requires the earth of his native land -- specifically holy earth -- in order to revitalize himself and restore his powers. The graves of his bloodline "make sacred the earth where alone this foulness can dwell. For it is not the least of its terrors that this evil thing is rooted deep in all good, in soil barren of holy memories it cannot rest."
Once Van Helsing and the other vampire hunters understand how important the boxes of earth are to Dracula, they spare no expense tracking them down. Dracula is clever to scatter them all over London, giving him many bolt holes in which to hide. But the hunters seek out the earth boxes one by one and sterilize them, giving Dracula nowhere to run. Eventually, he must flee England for Transylvania, pursued by Van Helsing and the others. The chase forms the climax of the novel, which ends when Dracula is uncovered in his final box of earth and destroyed.
Some of the most notable film adaptations of "Dracula" -- including those starring Bela Lugosi, Christopher Lee and Frank Langella -- eschew the use of boxes of earth in favor of the more traditional coffin. Other versions, however, make mention of the boxes or at least variations of them. The original "Nosferatu," released in 1919, shows images of coffins full of earth and rats. A 1973 version starring Jack Palance as the Count uses the earth boxes as a key plot point, stating that Dracula needs to sleep in his native earth. Perhaps the most prominent use of the boxes in a movie comes with the 1992 version starring Gary Oldman, which recreates many sequences directly from the book and shows the Count regenerating in a box of earth at one point.