Without plants, there would be no oxygen and nothing to prevent bunnies from discovering that humans taste delicious. Add some hydrogen for a protective moat with today’s Groupon: for $20, you get $40 worth of hardy bog plants and water lilies at Lilypons Water Gardens in Adamstown.

For nearly a century, Lilypons Water Gardens has sown, cut, and sold fresh flowers and plants to fill water gardens with gentle serenity and natural lushness. Line a lagoon with a delicately flowering arrangement of pink beauty, a rose-hue lily that produces a large number of flowers in low light conditions ($29), and the queen of whites, an Australian hybrid with cup-shape blossoms that vary from pure white to a pale blush pink ($29). The green thumbed can plant a handful of curly mint, which imbues gardens with a minty sweet smell with ruffled foliage ($9), or cattails, large, tall, pod-shaped plants that warn travelers of nearby water and man-eating turtles ($9).

Aquatic flowers and plants bring color and greenery to a watery environment, adding necessary nutrients and portable oxygen factories. Each Lilypons plant is grown locally and picked fresh to adorn patrons’ water gardens or provide suitable valentines for oft-neglected neighborhood grendels.

This deal is valid in-store only, and excludes lotuses, tropical water lilies, and tropical bog plants.