Tough Plants for Dry Shade

I garden in a tough place.  OK, it is in Zone 8, so I can’t complain about cold winters or unfair frosts.  It’s a tough place because it’s dry.  Victoria B.C. has a Mediterranean climate, which means wet winters (but not as wet as some people think) and dry summers.  Not too hot, but dry.  Beth Chatto’s book The Dry Garden has a permanent spot on my bedside table.

In addition, on my 50′ x 120′ piece of paradise, there are four large maples (probably Norway), a big weeping birch and a tree of heaven (Ailanthus), which some may consider a tree from hell for its habit of sending up suckers and seeding profusely.  The soil is a sandy loam, emphasis on sandy.  Drainage is excellent, but much of the space available for growing plants is infested with tree roots, the fibrous feeding roots of maples, which suck up most of the available moisture and nutrients.

There are plants that will put up with these onerous conditions.  Some of them have weedy tendencies, but who’s perfect?  Gardeners with big, greedy trees to contend with can’t afford to be too fussy.

Lychnis coronaria (Rose campion). Grey-green foliage. Surprisingly shade tolerant. Magenta or white flowers in high summer. The white form is elegant. Seeds profusely.

Linaria purpurea (Toadflax). Tall skinny spikes with (mostly) dark purple flowers like tiny snapdragons, in summer. Also pink and even purple/white variegated types (rare). Another terrifically prolific seeder that does well in sun or shade.

Campanula persicifolia (Peach-leaved bellflower). Purple-blue or white cup-shaped flowers in summer — quite showy.  This one seeds vigorously and spreads by offshoots as well. Can be sneaky — once you have it, you have it everywhere.

Digitalis purpurea (Common foxglove). The white form is incredibly elegant, rising out of surrounding foliage in late spring/early summer. Even the ordinary magenta-pink kind looks better than nothing. It has “presence,” if nothing else. Another keen seeder. It’s a biennial, so the first year there is a rosette of leaves, the second year it blooms. With a certain amount of “management” you can have the white form only.

Stachys lanata (Lamb’s ears). A woolly grey plant with tiny pink flowers, usually recommended for sun, but does fairly well in shade. Looks elegant just as it is coming into bloom, especially against a background of darker foliage. Also seeds heartily. (Do you see a pattern here?  With all of these plants, you have to be vigilant about deadheading and pulling up unwanted seedlings, but you will always have some of them around).

Alchemilla mollis (Lady’s mantle). Interestingly shaped leaves that display water droplets beautifully. Clouds of tiny yellow-green flowers in late spring. Only moderately pushy.

Helleborus argutifolius (Corsican hellebore). In good conditions, this can be a big, fat shrub-like plant, 3 feet either way.  When competing with tree roots in shade, it’s sparser but still a presence. It blooms in winter — big clusters of icy green flowers which last well into spring, when they should be cut down to leave room for the new shoots.  This one seeds as well, but not as recklessly as the previously mentioned subjects.

Helleborus orientalis (Oriental hellebore). I have been really impressed by how well this one performs here.  It blooms prolifically, right under the maples (which have not leafed out yet, in March and April).  I cut the bloom stalks down in May, at the same time removing the rattiest leaf-stalks.  The dark green leathery five-lobed leaves maintain a solid presence in the beds throughout the summer.  Colours range from white (pure or spotted pink and purple) through a range of pinks to purples that can be almost black.

Anemone huphensis (Japanese anemone). The single white form is very reliable. It blooms late in the summer and into the fall, not as profusely as it would in better conditions, but…  The downside of this one is that it spreads by running roots, which can be a good thing, but usually isn’t.

Ferns, especially the genus Dryopteris (notice it has “dry” in its name), as well as the native species Polystichum munitum (Western sword fern) and Blechnum spicant (deer fern).  Ferns are solid, reliable and the opposite of weedy.

You can count on these plants to provide a solid foundation, even in dry shade. Then you introduce more refined subjects (lilies, hostas, daylilies, etc.) and try to keep them going.  Between the tree roots and the rowdy, self-seeding, colonizing tough guys, it can be a struggle!

More (relatively) tough plants in a future posting.