Like several other writers of her period, Burnett presents a good deal of the dialogue in The Secret Garden as "Yorkshire English"—or just "Yorkshire," as her characters refer to it. The narrator and the characters born into privilege all speak in "standard" and uninflected English. The natives of the region into which Mary Lennox is brought have their dialogue represented in a very different way, however. This starts early, as can be seen in Chapter 4, when Mary meets her maidservant Martha and astonishes her with her uselessness in looking after herself:
Martha sat up on her heels again and stared. She spoke in broad Yorkshire in her amazement. “Canna’ tha’ dress thysen!” she said. “What do you mean? I don’t understand your language,” said Mary. “Eh! I forgot,” Martha said. “Mrs. Medlock told me I’d have to be careful or you wouldn’t know what I was sayin’. I mean can’t you put on your own clothes?”
Burnett uses "Yorkshire" as a way to invest the novel with a sense of local color. "Yorkshire" is also treated like a language that Colin Craven and Mary learn, and which they speak with "native speakers" as a way of extending friendship and making themselves better understood. Having her local characters "speak" in this way distinguishes them from others and allows the reader to feel immersed in the environment of Thwaite and Misselthwaite. The reader "learns" Yorkshire along with Mary and Colin, and the narrator—or sometimes even the speaker—often provides "translations" if the words are too far from standard English. Martha does so here, as Mary literally can't understand her language.
Sometimes the expressions Yorkshire people use need quite a lot of explaining, as "Yorkshire" contains both nonstandard English spelling and lots of local idioms and similes. For example, Mary is thin and gawky as "a young plucked crow" to the gardener Ben Weatherstaff, and he himself is "tough as a white-thorn knobstick."
Rich characters imitating the speech of working-class ones in contemporary novels might be taken as being extremely patronizing and classist. In The Secret Garden, though, the Yorkshire characters seem to love the children's imitations of their speech. This perhaps speaks to Burnett's own privileged background and to her own distance from British life as an American emigrant.
