Vancouver Specials: Plants That Love Rain

Credit: Terry Guscott

I am one of those people who smiles when it rains. It’s such an important part of this province – without it we wouldn’t have our wonderful green forests and lush gardens. The past few summers in B.C. have been very dry, and I can never understand why all gardeners don’t install cisterns to catch rainfall for watering their gardens during those arid summer months.

Achemilla mollis

Even those who don’t love rain as much as I do can appreciate the beautiful effects it brings to our winter and spring gardens, especially in warmer zones, where we’re able to wrap up and go into the garden during January and February. Have you ever noticed how broad-leaved evergreens seem to glow after heavy rainfalls? Camellias are a good example; their pale-green flower buds are fully developed in winter and the contrast against the dark glossy foliage is quite stunning. They look as if they can’t wait to burst into flower at the earliest mild spell. If you would like a camellia that takes this all just one step further, plant Camellia transnokoensis, which in its native habitat on the slopes of Mt. Noko in Taiwan grows to be a large shrub or small tree up to 8 m (26 ft.) in height. We have it at UBC in the Asian garden, where it tends to be a small shrub with airy branches to 2 m (61⁄2 ft.) in height. Unfortunately, it’s only hardy to zone 8, but if you’re in this zone, it’s a must-have for winter enjoyment. The leaves are quite small and in each leaf axil there are tiny oblong buds with bright-pink to dark-red edges that seem to glow in the rain. The foliage is a light, almost brownish green and is often more bronze toward the tips of the branches.

Sanguisorba minor

It requires a good woodland-type soil with plenty of leafy compost added at planting time. Try to choose a spot where dappled shade will protect it from the heat of the summer afternoon sun. Those buds, of course, do open into small, single, sweetly scented blooms in March. But the weeks of joy they give before opening is quite magical. Variegated evergreen broadleaf shrubs add a whole new dimension to a winter garden. A long-time favourite of mine, Elaeagnus pungens ‘Maculata,’ is a selected cultivar of the shrub native to Japan. It spreads to 3 m (10 ft.) in height and width, but I hasten to add that it responds well to pruning so it can be made to fit a smaller garden. It doesn’t seem too fussy about soil as long as it is well drained and planted in the open.

Camellia transnokensis

This is a dense and somewhat spiny shrub, with interesting new shoots that are covered with rusty brown scales, giving it an almost woolly look and texture. The oblong leaves are about 10 cm (4 in.) long, with a lustrous upper surface and a silvery underside. And in the case of ‘Maculata’ the leaves are boldly marked with wide yellow variegation on the upper surface. This plant fairly glows and should be planted in a mixed border where it can be seen from a favourite window in your home. That bright golden yellow on a dreary grey winter day is a real spirit lifter.

Cornus alba ‘Sibirica’

Our native red osier dogwood (Cornus stolonifera) puts on a fine display of colour and is very hardy. The bare red stems glow against snow or rain. Another hardy favourite, Siberian dogwood (C. alba ‘Sibirica’), is native from Siberia down through China. It tends to thrive in damper areas, so look for places where water lingers in your garden. To get the best colour from the stems, prune them really hard, almost back to the ground, in early spring, as the new shoots produced in spring and summer will yield the brightest red stems the following winter.

Alchemilla erythropoda

Mosses provide the brightest emerald green in our coastal woodlands during the rainy season. (I’m a big fan of mosses, so you can see why I get mixed reactions from gardening friends, especially those who spend their entire time trying to eradicate moss from the lawn!) In the apartment building where I live there is a narrow lawn between the street and some tall evergreens that surround the building on the north side. Not surprisingly, that strip of lawn is mostly moss and it glows during winter. Then, in late February to early March, the scene becomes amazingly vibrant when the drift of evergreen Euphorbia amygdaloides var. robbiae blooms. Before I go any further, I must warn new gardeners that this particular euphorbia can become a problem, as it spreads freely by underground runners. In the right spot, though – as this one is, under the shade of a giant Himalayan cedar (Cedrus deodara), where little else will grow – the bright, almost luminous blooms can brighten the dullest day. This euphorbia is native to the wooded mountain slopes of northwest Turkey and is hardy to zone 6 and up. Dark evergreen leaves grow in whorls on stems that are about 24 cm (10 in.) tall. The leaves are evergreen, but here’s a good tip: to encourage great blooming the following winter: cut them right back to the ground after they have finished flowering in April. Be sure to wear gloves when doing this as the sap can cause severe skin rashes in some people. ­­

Cronus stolonifera

Asplenium scolopendrium (hart’s-tongue fern) is a dramatic fern that’s widely distributed throughout the world. Hardy in zone 6 and up, it tends to be evergreen in our coastal climate. Lovely, strap-shaped, leathery, bright-green fronds grow to 40 cm (16 in.) in length. The upright fronds reveal their herringbone arrangement of sori on the back. This is a great plant to grow on the north side of your home. When wet, the wide fronds reflect light, and mixed in with other ferns and hostas, it creates an attractive tapestry. One couldn’t write a piece about rainy-day plants without mentioning Alchemilla mollis (lady’s mantle). This clump-forming perennial has rounded leaves up to 15 cm (6 in.) across, covered with soft tiny hairs that capture rain. After a shower, each leaf holds a treasure trove of sparkling drops – truly a beautiful sight. Its attractive, frothy chartreuse flowers bloom in spring to early summer. Lady’s mantle is considered by some to be a garden thug, as it seeds itself about freely. But it softens garden edges to perfection and if it comes up where you don’t want it, dig it up! If you cut off the flowers when they start to brown, this can really cut down the amount of seeding. Or you can cut the whole plant back at that point, water it well, fertilize it and, presto, you have a new set of leaves and no seedlings. There is a close relative that tends not to seed as freely, Alchemilla erythropoda. The leaves are a little smaller, less hairy and have pointed lobes on which the raindrops tend to puddle, as opposed to looking like diamonds. It’s a good one for open, sunnier spots. Both are native to western Russia and the Caucasus, making them hardy in zone 4 and up.

Salvia officinalis ‘Berggarten

Another charming perennial that looks absolutely smashing with raindrops glistening on its pretty leaves is Sanguisorba minor or ‘salad burnet’, native throughout Europe into western Asia and hardy to zone 4 and up. Its pinnate basal leaves are up to 15 cm (6 in.) in length with 7 to 21 oblong to elliptic leaflets. The flowering stems have smaller leaves but produce reddish/pink rounded flowerheads in late spring and early summer. Young leaves of this plant chopped and added to salads give a strong cucumber flavour. And while we are talking about flavourful herbs, the sun- and drought-loving sages also look wonderful dotted with rain throughout fall and early winter. I particularly admire the German cultivar Salvia officinalis ‘Berggarten’ with its very broad and round typically downy-grey salvia leaves. While this one is hardy only in zones 7 and up, it’s worth planting as an annual in the many colder parts of our province. The following plants are hardy to the zone number indicated (turn to page 10 for our zone chart): Alchemilla erythropoda – zone 3 • Alchemilla mollis (lady’s mantle) – zone 4 • Asplenium scolopendrium (hart’s-tongue fern) – zone 6 • Camellia transnokoensis – zone 8 • Cornus alba ‘Sibirica’ (Siberian dogwood), Cornus stolonifera (red osier dogwood) – zone 2 • Elaeagnus pungens ‘Maculata’ (thorny elaeagnus)– zone 7 • Euphorbia amygdaloides var. robbiae (Mrs. Robb’s bonnet) – zone 6 • Salvia officinalis ‘Berggarten’ (common sage) – zone 7 • Sanguisorba minor (salad burnet) – zone 4 David Tarrant of the UBC Botanical Garden is a well-known gardening expert, author, and host of Spring, on HGTV. PHOTOS John Glover: Cornus alba ‘Sibirica’, C. stolonifera, Euphorbia amygdaloides; Daniel Mosquin: Camillia transnokoensis; Terry Guscott: Alchemilla mollis, Asplenium scolopendrium, Salvia officinalis, Sanguisorba minor; Thompson and Morgan (UK) Ltd: Alchemilla erythropoda; Great Plant Picks: Elaeagnus pungens ‘Maculata’