tough plants

My Tough Plants #4: Hellebores

Unlike the other plants in this series, this one doesn’t have a reputation for weediness. And yet, in my garden it seeds around freely, to the point I’ve pulled out seedlings that are too numerous or in the wrong places. So technically, hellebores can be weeds. It’s all a matter of being in the right place, after all.

Corsican hellebore

I have two species of hellebores here: the tall, jagged-edged-leaved Corsican hellebore (Helleborus argutifolius), with lime green flowers in winter and early spring; and the oriental hellebore (Helleborus orientalis), with flowers in shades from white to dark purple and big, round-edged leaves.

Both put up with shade and tree roots, and are of no interest to deer. The plants are evergreen. They don’t vanish in autumn; in fact, that’s when they perk up and start to think about blooming. Buds appear by Christmas and flowers are present until mid-spring. At that point, seeds are ripening, there’s lots of other stuff coming on, and it’s time for the hellebore bloom stalks to be cut down and removed. The leathery, dark green leaves look fine through the summer. A decent watering every week or two is helpful in our dry summers. If too dry, oriental hellebores flop and look pathetic, splayed out on the ground like they’ve given up.

Oriental hellebore

The plants are long-lived and reliable. Maintaining them is simple. Corsican hellebores bear their flowers and leaves on the same stems. By the time the flowers look tired and seedy (May in my garden), fresh stems have appeared. I cut down the old stems at ground level and that’s that. The plants do have a tendency to splay as the stems lengthen. In spots where I don’t want them to flop onto other plants, I pound in 3 or 4 stout stakes around a plant and surround it with twine. I untie this before the cutting down operation and replace it afterward, to support the developing new stems.

Oriental hellebores produce separate leaf and flowering stems. I cut down the old leaves in spring, just about the time buds appear. New leaf stems grow along with the flower ones, so the plant rapidly plumps up again. I cut down the old flower stems by June to prevent seeding. When cutting down the old flower stems, make sure you don’t cut leaf stems by mistake (says the Voice of Experience).

Hellebores do have one annoying pest — aphids. They love the new growth and can multiply alarmingly on fresh leaves and even on flowers. I wash them off with water, either from a spray bottle or with the hose. Over the years, I’ve seen one or two plants afflicted by what I suspect is some sort of fungal disease; they produce fewer flowers and stunted leaves. The best “cure” might be to remove the sick plant and replace it with a fresh one, keeping in mind that if the problem really does originate with a soil-dwelling fungus, the new plant may be affected too.

Hellebore “Ivory Prince”

Almost all of my hellebores are the basic species. I acquired my oriental hellebores by scooping up a clump of seedlings at the two-leaf stage with a teaspoon from a public planting. (I admit the deed!) That’s why they’re all in shades of pinky-purple, although the colours vary a bit within the group. I’ve also bought a couple plants, one white with pink speckles and a creamy yellow one (whose flowers almost always turn rusty brown at the edges, so it’s a disappointment). I also bought a plant of the variety called “Ivory Prince.” It lives in a big blue pot and is quite a feature in February.

Plant breeders have been busy with the hellebore family, so a huge variety of colours and flower types is available. I’m intrigued by the ones with slate-coloured or almost black flowers, but the frilly double forms in shades of pink look like too much of a good thing to me.

Hellebores, especially the Corsican type, are good “anchor” plants in a perennial bed. They have enough presence to impart elegance to spots that include some of the weedier tough plants. Hostas are good company for hellebores. Their leaves are similar in size but different in texture, and they like the same conditions. (In my rooty patch, however, hostas do best in pots parked near the hellebores, rather than planted in the ground). Ferns look good near hellebores too, specifically the tough Dryopteris types. In small gardens, Corsican hellebores may be used like small shrubs, underplanted with bulbs and a groundcover such as plumbago (Ceratostigma plumbaginoides), which has electric-blue flowers in late summer. I prefer it to periwinkle, which is evergreen and overly vigorous.

Something to consider — Corsican hellebore plants can exude a distinctly skunky aroma, especially in warm weather. If you grow them, be prepared for questions about pot smoking. On the other hand, if you wish to indulge discreetly (pot is legal in Canada come October 17th), you can say, “Oh, you must have caught a whiff of the hellebores.”

Corsican Hellebore, variegated hosta (in pot), and hardy cyclamen, Fall 2010

My Tough Plants #2: Rose Campion

Rose Campion… Sounds like a good name for a romantic heroine. But no, it’s one of the common names of a plant, another tough, almost-weedy one that does well in my garden.

This common name, although charming, doesn’t really suit the white-flowered form (see the featured image at the top). Maybe that’s better represented by “Bridget-in-her-bravery,” although that’s quite a mouthful. I tend to call it Lychnis coronaria, or simply lychnis. That’s not quite right either, since (according to Wikipedia), the official Latin name is now Silene coronaria. Wikipedia also cites other common names: mullein-pink, Bloody William, and lamp-flower.

This is another relatively short-lived perennial that seeds heavily. Fully grown, it’s between one and three feet tall (30-100 cm). The growth habit is basal clumps of grey-green leaves with a sort of suede texture, similar to lambs’ ears (Stachys byzantina) but not as fuzzy. In spring they send up flowering stalks and bloom mainly in June and July. The flowers come in two main colours — bright magenta-red and pure, bright white. I’ve read there are pink forms and a white-with-pink-eye combination, but I’ve not seen either of those.

Deadheaded flowers of Lychnis coronaria Rose campion

This is the result of an hour’s worth of deadheading. That’s a 750 gram yogurt container.

As with purple toadflax, to get the best from this plant, you have to deadhead. And unfortunately, deadheading rose campion means snipping off each flower individually, using scissors or small clippers. Each plant produces dozens of flowers, so weekly deadheading sessions are needed. That keeps them blooming into late summer and prevents copious seeding.

Close-up of deadheaded flowers of Rose campion Lychnis coronaria

Spent flowers (and potential seed pods)

The spent flowers go through a limp stage and then quickly become knot-like seed pods. Left to their own devices, the pods ripen over several weeks. When mature, they open up at the top, like tiny urns poised to spill hundreds of seeds.

I generally deadhead flower-by-flower into August. By then, the plants are slowing down. They produce fewer buds and the bloom stalks start to look thin. At this stage it’s best to cut them down at the base, leaving the basal clump of leaves to finish out the season. In spots with a bit of moisture and/or shade, it’s possible to cut the stems by half in August for a fresh batch of late flowers in September. Because of the rather tedious deadheading requirement, I recommend keeping the number of plants relatively small (no more than 10) and situating them where you can get up close to trim off the flowers as they fade.

Here, rose campion looks fairly good all winter, although older plants may have quantities of dead leaves that resemble chamois leather. At my place there’s no shortage of rose campion, so I don’t hesitate to yank out any that are past their best. It copes well with the occasional snowfall and winter temperatures of -5 to -10 C (10-20 F).

White Lychnis coronaria and unknown (to me) Euphorbia

Lychnis coronaria performs best in sunny spots, but is quite tolerant of light or partial shade. It doesn’t mind dry conditions, sandy soil, and competing tree roots. The white flowers are rather insistently bright, so a large number of plants in one spot can be too much of a good thing. The combination of white flowers and greyish foliage is elegant, especially with the sharp chartreuse, such as that of euphorbias. The magenta form looks best with other strong colours, rather than pale pastels. The two colour forms look fine planted together.

Rose campion is of no interest to deer and needs minimal watering. I suspect it prefers well-drained soils, although I’ve seen references to it growing well in clay soils. You can find them here (see the comments) along with more info about rose campion.

My Tough Plants #1: Purple Toadflax (Linaria purpurea)

My garden, as I’ve said many times, is a 50-by-120-foot suburban lot with the usual house, driveway, garage and paved walks. Among those elements are half a dozen beds or borders containing combinations of shrubs, perennials, and self-sown annuals. There are also small areas of grass (sometimes called “the lawns,” although that sounds rather grand).

The soil is a light sandy loam, with good drainage. The climate is semi-Mediterranean, which means mild wet winters and dry summers. Recent summers have been drier and warmer than normal. Most of the plantings are affected to some extent by four large Norway maples, a big birch and a medium-sized Tree of Heaven (Ailanthus altissima).

In this difficult situation — dry, rooty shade — a few reliable tough plants perform quite well, because they are tough and almost weedy. Properly managed, they can be quite ornamental. I plan to write several posts this summer about how I use these plants in my garden.

First up is Purple Toadflax (Linaria purpurea). Apparently, the leaves resemble those of the flax plant, which explains the “flax” part of the common name and the “lin” (linum is Latin for “flax”) in the genus name. I’m not sure where the toad comes in.

The plant grows between 1 and 3 feet (30 cm to 1 metre) tall. In shade, it can reach 4 feet. It’s somewhat slender, so inserts itself easily among other plants without crowding. Most plants have between 4 and 10 stems. The stems are stiff and never need staking.

The individual flowers are like tiny snapdragons. They cluster in spiky racemes at the tops of the stems. The standard colour is medium to dark purple. I’ve had a few plants whose flowers are purple and white, but they’re rare. Pink flowers are more common than the bicolours. They’re a fairly pale pink, though; their main interest comes from being different from the norm. The standard purple is a fine colour, contrasting well with the grey-blue-green of the slender leaves.

Purple toadflax is of no interest to deer. It grows well and blooms reliably in dry, rooty soil and shade. It thrives in sunny spots. Bumblebees love it.

What’s not to like? Well, I did say it’s a quasi-weed. Left to its own devices, it blooms in May and June. The flowers are succeeded by seed pods that look like tiny green beads. At this point flowering stops. Seeds ripen by summer’s end and scatter when the plants are disturbed. The following spring hundreds of seedlings emerge, producing more toadflaxes than anyone wants. An untended patch of toadflax is reminiscent of gravel parking lots, not garden borders.

Rigorous deadheading is the way to curb the plant’s weedy tendencies. Clip off the spikes of bead-like seed pods as soon as they form. You can either cut each thin side-stem or wait until the whole raceme has pretty much finished flowering and cut the main stem just beneath the flower cluster. The plant will put out new flowering side-stems and keep blooming all summer. A bonus of this process is that the foliage of plants growing in sunny spots turns interesting shades of pink in autumn.

The trick is to deadhead before the seeds ripen. Inevitably, a few plants escape my notice. I discover them when I’m doing fall cleanup, by which time the tiny seeds scatter far and wide. A desperation measure for this situation is to carefully clip the seed-bearing top of each stem and transfer it into a pail or similar container, preventing seed scatter. I suspect semi-ripened seeds are able to finish maturing in the compost pile, so it’s best not to compost them unless you’re sure your heap achieves temperatures high enough to kill seeds. Mine doesn’t.

This is why I know how well toadflax blends into plantings. I don’t remember ever actually planting it. I go through the beds in spring and remove excessive seedlings and badly-positioned plants.

Toadflax is a short-lived perennial. Individual plants persist for two or three seasons. Eventually, they get woody at the base and perform poorly. By that time, though, there are more than enough young plants to replace them.

I wouldn’t recommend purple toadflax for mass plantings. The skinny, diagonally placed leaves produce a visually tedious herringbone tweed effect. Besides, this mass planting effect is what you get when you let toadflax self-sow with abandon. I like them best among other plants with contrasting leaf shapes.

More info about Purple Toadflax is available at the Missouri Botanical Garden site and Wikipedia.

Thugs, Prima Donnas… and Mulleins

When I began making this garden in 1992, I didn’t have a lot to spend on the project, so I was happy to fill up the space with pass-along plants from other gardeners, waifs and strays of unknown provenance and tough, easy-to-grow self-seeders. Many of these are still with me, prospering despite the sandy, tree-root-infested soil and dry summers. I’ve written about them here already.

Like most gardeners, I’ve also wanted to grow more challenging plants — refined roses, delphiniums, oriental lilies and (the gardener’s supreme challenge), Himalayan blue poppies. For several years, I pored over the catalogues of a nursery located in the Fraser Valley, and every year brought home a selection of their offerings. I ordered seeds of carefully-researched perennials and successfully raised seedlings. Some of those acquisitions are still with me, and a few are doing well.

Geranium “Anne Folkard” and Clematis integrifolia

Dictamnus albus

But. (There’s always a “but”).

My garden is now bursting full. If I want to try something new, something has to be removed. Quite a few of the purchased and grown-from-seed plants are long gone, remembered only from a sad collection of labels in my garden shed. Cosmos atrosanguineus, Gaura lindheimeri “Siskiyou Pink,” Lamium maculatum “White Nancy,” R.I.P. Farewell, Coreopsis verticillata “Moonbeam,” Trifolium repens “Dragon’s Blood” and Cimicifuga racemosa.

The good old tough plants are, of course, thriving. Hellebores, toadflax, rose campion, lamb’s ears, lady’s mantle, foxgloves, fireweed and a number of ferns. The fussy, “quality” plants, however, live in pots. No root competition and individual attention from the gardener in the form of fertilizer and water.

Potted Oriental Lily and Zeke the Cat

Pots aren’t foolproof, however. I bought this potted lily a week ago to replace two that gave up the ghost because I allowed self-seeded “hitchhiker” plants to take over their pots. Another threat is excessive winter wetness. A couple of my delphiniums perished from that, and it was literally death to my idea of growing blue poppies in pots. Better results may be possible if one ensured really good drainage and situated the pots in a spot out of the rain (and remembered to check for excessive dryness at times over the winter).

For the past three years, my blue poppies have had their own bed near a magnolia. Last year they bloomed; this year they decided to give it a miss, even though they look healthy. I am catering to them with mulches of compost and peat, extra fertilizer, regular watering and shade from afternoon sun. As in farming and hockey, maybe next year.

Tough plants need to be controlled and discouraged. Delicate beauties need to be cosseted and coaxed. Pots aren’t always a solution and there are no guarantees.

But mulleins look great most of the time. I have given over my former vegetable patch to herbs and mulleins — Verbascum olympicum and Verbascum chaixii. Even before they bloom, they look interesting.

Verbascum chaixii rosette from above

Mulleins seem to know that anticipation is almost better than fulfillment. They take a long time to grow their bloom stalks and look great through the process.

Olympic mulleins, Verbascum olympicum

In the end, I have to ignore the distinctions between tough plants, refined plants, purchased or self-seeded. Right now, the garden looks pretty good. Right now. That’s what counts.

Lessons Re-Learned

Epimedium “Frohnleiten”

Today was my first full day of gardening since last fall (not counting the pruning session in March). While generally happy with things in my little plot, I was reminded of a few truths for those who garden in small spaces (anything less than half an acre).

1. Never plant any shrub that suckers, no matter what sentimental associations it may have, or that it’s a native plant, or that some garden writer you admire spoke highly of it. This includes Oregon grape (Mahonia aquifolium), snowberry (Symphoricarpos albus) and the common lilac (Syringa vulgaris). It also includes the woody perennial (not quite a shrub) Phygelius (also known as Cape figwort). I have all of these, and spend several unpleasant hours every year yanking, snipping and sawing their adventurous shoots. It’s an especially unrewarding task because I know most of the shoots will re-sprout and new ones will join them. It’s too late to remedy my unfortunate plant selection decisions, however, since the original shrubs, now huge and deeply rooted, would require immense labour or dynamite (or both) to dislodge them. Beware of rampaging groundcovers as well, such as ivy and Vinca major. Even the deceptively dainty-looking Vinca minor has thuggish tendencies.

2. If your garden looks like a hopeless mess at this time of the year, do three things before you give up on it: mow the lawn, edge the beds and cut down last year’s old stalks. This will instantly impart the look of a managed garden and motivate you to make further improvements by weeding, loosening the soil, introducing new plants and mulching. Even if the plants occupying the beds are nothing special, this treatment will make them look better. (This applies to perennial and mixed ornamental beds; vegetable gardens are another thing altogether).

3. If your garden is mainly one of tough, drought- and tree-root-tolerant perennials and shrubs along with various bulbs, don’t expect plants with more exacting requirements to do well or even survive without a lot of special attention. They are already having to put up with less than ideal growing conditions and will be no match against tough, colonizing plants such as peach-leaf bellflower, lamb’s ears, toadflax and rose campion. If you can’t provide them with a separate bed, keep an eye out for their early spring growth and make sure they aren’t overwhelmed by their robust, faster-growing companions. I say this after rescuing Thalictrum delavayi “Hewitt’s Double” and even Geum chiloense “Mrs. Bradshaw” (which isn’t generally considered a delicate thing, but is treated like one in my rooty patch). As for my blue poppies (Meconopsis), they have their own slender slice of earth to dwell in, but I wonder if it’s too close to a rather hefty magnolia. They have sprouted out quite well, all seventeen of them, so I have hopes.

Henry Mitchell said, “The life so short, the craft so long to learn. This was said about literature, but it really fits gardening better.” Very true.

Fiddleheads of Dryopteris filix-mas

Bellflowers, Peach-Leaf and Others

My somewhat cranky post on Peach-leaf Bellflower has to be one of the most visited in this blog’s archive. It seems a lot of gardeners are interested in bellflowers. Because that post was a diatribe against Campanula persicifolia, I thought I would take a more temperate look at them now, when their first flush of bloom is nearly over.

Peachleaf Bellflower

The genus Campanula, or bellflowers, is huge — more than 500 species. It includes perennials, biennials and annuals ranging from a few inches high to six feet, but most seem to be in the one to three foot range. They occur in a variety of temperate habitats, including woodlands, grasslands, alpine and arctic regions. Dozens of species have found their way into gardens and have attracted the attention of plant breeders, resulting in many horticultural varieties.

I personally have experience with only a few of the bellflowers. Only two, actually. I recall the biennial Canterbury bells called “Cup and Saucer” from childhood, but have never grown it myself. Someone once gave me a plant of a creeping type, possibly a cultivar of C. carpatica, but it did not last. The two that have, and will probably be here forever, are C. persicifolia, Peach-leaf Bellflower, and C. rapunculoides, whose common name — Creeping Bellflower — should give any gardener the creeps. The authors of Perennials for American Gardens warn that “it must never be introduced into gardens, except into the wildest areas.” Well, it somehow got introduced into my garden, although not by me. At present, there is a clump growing out of asphalt on the edge of the driveway and another at the base of a Norway maple. The latter appears to be spreading slowly. Every spring I dig up the outermost sprouts, but I suspect it’s gaining ground. I also see it over the fence near my shed, and have conducted a little herbicidal warfare to keep it out.

The interesting thing is that the rapacious C. rapunculoides is quite attractive — more so than C. persicifolia, whose flowers are wide open, outward facing cups, while those of the former are downward-facing in the true bell-like manner, with elegant pointed edges.

Creeping Bellflower

On my way to work by bicycle I admire a nice clump of this plant growing at the foot of a bus stop sign, in the crack between sidewalk and curb. It’s obviously never watered except by rain (nonexistent at this time of year) or cared for in any way, but puts on a show every summer.

But — and it’s a big “but” — these two bellflowers are inveterate spreaders. Rapunculoides spreads mostly by underground rhizomes, forming fat tuberous storage roots. Every bit of root is capable of forming a new plant, so careful digging and disposal (not in the compost heap) is needed to remove it. Mostly it’s impossible to get rid of it entirely which is why it needs to be watched carefully and extracted as much as possible every spring.

Peach-leaf bellflower distributes itself both by seeds and underground roots, but is generally a bit easier to remove, except when it becomes entrenched among other desirable plants, when digging it up means digging up the entire bed. Careful deadheading can prevent excessive seeding, but the more plants you have the harder it is to keep up with the spent flowers about to become seedheads. The purest deadheading technique is to snip each flower individually, allowing the new buds forming lower on the stem to develop. This is fine if you have only a few easily accessible plants, and more time and patience than I have. Cutting entire flowering stems once most of the blooms are over works quite well. My plants manage to rebloom once or twice after this treatment.

So do I still think of Peach-leaf Bellflower as a “garden enemy?” Not really, but I suggest that gardeners think carefully before introducing it, especially to neat and tidy gardens. It’s actually one of the tough plants that are valuable in adverse conditions (such as dry shade), but become a little too pushy in favourable ones. In such situations, I would advise a gardener who wants to try campanulas to visit a good garden centre and obtain some of the horticultural named varieties, which tend to be less aggressive.

And for those who already have these two bellflowers, all I can say is that they create an opportunity for the gardener to exercise some mental discipline. Fight or negotiate? Attack or maintain a watchful peace? Who says gardening is a genteel pastime?

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