Daphne x transatlantica 'SUMMER ICE'

Daphne is a large genus of about 50 species. They are deciduous or evergreen, and commonly renowned for their very fragrant flowers. Hybrid daphne transatlantica is a result of crossing two species of formerly European origin (d.caucasica and d.collina) but the plants used for cross pollination were cultivated in the USA. There were selected those with reliably evergreen or at least semi-evergreen foliage.

Summer Ice is a variegated form of hybrid daphne caucasica found by Bob Tichnor of Oregon State University’s North Willamette Research and Extension Centre in Oregon, USA. The source does not say whether the plant is a mutation of unnamed hybrids or an existing variety Jim’s Pride with green foliage. From late spring until the last sunny and warm days of summer it produces small, tubular flowers, almost white inside, and pink to pale lilac outside. They have an intoxicating perfume, sweet and strong that you simply must have one in your garden. Leaves are narrowly elliptic, 3-5 cm long, slightly glossy, medium to dark green with a thin and very elegant creamy white to pale banana yellow rim. They are semi-evergreen or evergreen in warm areas and mild winters.

Summer Ice a fuss-free shrub which is something you cannot say about every daphne. It may seem to grow slowly but it bushes out quickly and you will be surprised what growth it can make in a couple of years. Left to its own devices it forms a handsome, dome-shaped shrub, almost one meter wide and tall. It needs no pruning or trimming for a nice shape, but it can take light pruning in late winter or early spring. Never prune too hard – trim only branches with leaves. The entire plant is toxic.

Daphne is usually slow growing, difficult to propagate, and detests transplanting. Hence its higher price on garden centre shelves. Yet once established it makes a beautiful shrub you will admire for many years. It naturally grows in sharply drained soil which is rather dry, yet not as dry as a xeriscape, which makes it an ideal rocky plant. Drainage is essential to keep it alive though Summer Ice will be quite happy in a normal garden soil of any pH. Keep it moist only for a few months after transplanting. Then do not water it ever again. It does not grow in pots. Do not fertilize but use soil fungi (mycorrhiza). Hardiness has so far been tested and proved to -24°C (USDA zone 6) but is expected to be a little stronger with some leaf drop.

Last update 30-06-2020