Benny gets onto Mrs. Montague's computer and changes her lawnmower order to a powerful Terrafirminator unit, intending to get revenge on the reds. However, the Terrafirminator goes out of control and destroys most of the two gardens while the gnomes wage a full scale war. Gnomeo makes it back to Juliet with the help of Featherstone. However, when he arrives, the Terrafirminator then frees itself, sending it flying. He tries to try to un-glue her, but he is unable to. She tells him to go, but he refuses. The two share a passionate kiss just as the lawnmower crashes into the fountain, self-destructing in the process. When everyone believes that both are dead, Lord Redbrick and Lady Bluebury decide to end the feud. Miraculously, Gnomeo and Juliet emerge from the ruins and the two clans celebrate.
The film ends happily with the red and blue gnomes finally coming together to celebrate their newfound peace. Tybalt is revealed to still be alive having been glued back together, Featherstone is reunited with his girlfriend after Benny finds and orders her online, Gnomeo and Juliet are married on a purple lawnmower, which symbolizes the new union of both gnome clans.