 Should these tricks actually make your flowers last the longest? I filled cups with water and added the quote-unquote magic trick to them and the results were surprising. The aspirin was an epic fail and seemed to fast-track her rose to its demise. The soda and penny and the sugar trick seemed to send our flowers to a tragic end, though not as quickly. The petals on both dried up and turned a kind of brownish color. The flower in the vodka had dried outer leaves, but other than that, it held up okay. In a surprising twist, spraying the outer petals with hairspray actually worked, and that flower has low-keep in thriving. And the rose that was left in plain water held up better than most of the others, so that might be the best way to go.