A 17-year-old girl scout from England was stabbed to death over a bag of weed her pals bought from a rival of her alleged attackers, a court heard this week.

Jodie Chesney — who was knifed in the back as she sat smoking with friends in a London park on March 1 — was allegedly targeted by two pot dealers who were furious her crew had snubbed their new strain of “Pineapple Express,” prosecutors told a jury at The Old Bailey courthouse.

In the attack, two men stormed Chesney in the dark and one plunged a knife in her back. She was not likely the intended target, the Evening Standard reported.

Earlier that day, Chesney’s friend had tried to buy a $25 bag of weed from Svenson Ong-a-Kwie, 19, a dealer accused of killing the Girl Scout with help from his partner, Manuel Petrovic, 20, according to the paper, which cited court testimony Tuesday.

When it took too long to get the pot, he instead bought a $45 bag from a different dealer, who delivered it to Amy’s Park in the Harold Hill section of London within an hour, the paper reported.

But Ong-a-Kwie showed up at the park anyway while delivering to Chesney’s friend’s older brother — at which point he may have seen his rival selling pot to her group, infuriating him, the paper reported.

“The prosecution suggest[s] that while Svenson Ong-a-Kwie was in Harold Hill he must either have heard or seen something that upset him,” prosecutor Crispin Aylett told jurors.

Ong-a-Kwie and Petrovic have denied killing the Girl Scout.