Dyslexic Daphne

Flowering now in the garden is one of the more fascinating woody plants we grow, Daphne pseudomezereum. This odd Daphne, hailing from Japan and Korea, is the only known Northern temperate plant that loses its leaves in summer, but regrows them in fall, for a wintergreen appearance in the garden. I should add that Daphne jezoensis also does this, but it has recently been determined to actually be the same species.

Despite being native to deciduous forests, research showed that the foliage of Daphne pseudomezereum is simply not adaptable to shade, since it burns up more energy in those conditions, than it generates. This is despite growing alongside other evergreen plants like Aucuba japonica, which survive just fine during the summer. To survive, the daphne developed a strategy of dropping leaves in late spring when the tree canopy darkens. When the canopy reopens with fall leaf drop, Daphne pseudomezereum regrows its foliage. As an experiment, we planted our plant in full sun, where it continues to act as though it was still in shade, and dropping it’s foliage until fall. It is speculated, but not proven yet, that the summer leaf drop might also help it avoid summer insect predators.

Recent research (2024) has also shown that compounds extracted from Daphne pseudomezerum cause HIV virus cells to stop multiplying, so the benefits of this amazing plant go far from it’s unique habit, and beauty. Mature size is 3′ tall x 3′ wide. Hardiness is Zone 5a-9a.

Physiology Plant, 2019 May 7;168(1):77–87. doi: 10.1111/ppl.12972