Clematis armandii – This is an evergreen species (native to China) with fragrant white star-shaped blooms from March to April. These are nicely contrasted by the dark green tapered foliage, which emerges with a hint of bronzing. Clematis armandii should be sheltered from drying winter winds and is best pruned immediately after flowering. Grows 15-20′ tall. Zone 7.
Magnolia stellata – Star Magnolia is an easy-to-grow species with slightly fragrant white flowers (with strap-like petals) that emerge before the foliage, usually March to April. It forms a small multistem tree or large bush, with dense green leaves – making it good for screening. This deciduous species prefers part to full sun with good soil drainage. Grows 10-15′ tall. Hardy to zone 5.
Akebia quinata ‘Shirobana’ – White-Flowered Chocolate Vine is a hard to find semi-evergreen vine (at least here in coastal BC) with palmately-compound leaves composed of five rounded green leaflets. It bears fragrant white flowers (both male and female on the same plant) in abundance from April to May. ‘Shirobana’ grows to 20′ tall and is hardy to zone 6.
Styrax japonicus – As the name implies, Japanese Snowbell Tree is a native of China, Korea and Japan – it features simple green leaves that usually turn yellow in autumn. Clusters of fragrant white bell flowers are borne in late spring, these are followed by dangling coffee bean-like seeds that persist through winter. A good choice for smaller yards. Slow growing to 30′ tall. Hardy to zone 6.
Hydrangea petiolaris (syn. H. anomala subsp. petiolaris) – Climbing Hydrangea is actually a clinging shrub with aerial roots (for support) that develop off the branches. It bears white lacecap form blooms in summer and although often recommended for shade gardens, is better in part sun. The deep green leaves turn yellow in fall, dropping to reveal reddish-brown bark. This species is slow growing and can eventually grow 40′ high. Zone 4.