Rodgersia’s leaves of distinction

Judith Adam

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Astilboides tabularis with Lamiastrum galeobdolon 'Herman's Pride' (Photo by Brendan Zwellling)
Astilboides tabularis with Lamiastrum galeobdolon 'Herman's Pride' (Photo by Brendan Zwellling)
Astilboides tabularis with Lamiastrum galeobdolon ‘Herman’s Pride’ (Photo by Brendan Zwellling)

When I started gardening, my interests were blossom oriented. I wanted magnolias, peonies, roses, hollyhocks and just about anything that promised lots of petal display. That time was well spent and a good education. I learned that flowers are fleeting and a necessary step in the process of making seeds, and that’s what a plant is trying to do when it blooms. When seeds are eventually formed, the plant’s work is done and it stops flowering. Of course, gardeners try to prolong flowering with deadheading, pruning, and fertilizing to encourage buds, but ultimately plant biology determines when to shut down flower formation.

Now, after three decades of gardening, I’m more interested in foliage display. I like plants with interesting leaves, both in colour and form, and I appreciate that they’re reliably on display for the entire growing season. One I particularly enjoy watching is shieldleaf rodgersia (Astilboides tabularis, syn. Rodgersia tabularis, Zone 6). Its broad leaves resemble lily pads, with prominent veins and wavy edges; they have a powerful architectural form and, to my eye, a primordial elegance. I wouldn’t be surprised to encounter this plant in a rainforest jungle, and it never fails to startle me by the front steps.

My favourite perennial plant expert, Allan Armitage, writes that A. tabularis lacks the nobility of other species, and for once I don’t share his point of view. Perhaps it lacks refinement, but it certainly makes up for that with bold character! Like all the rodgersias, it looks at home near a pond, likes rich moist soil and partial shade, and sends up a five-foot (1.5-m) feathery white flower panicle in late spring. Mine is grown in full shade and has never flowered, but this spring I purchased a second shieldleaf rodgersia to plant in brighter light, and perhaps I’ll see the flower next spring. I can just imagine Dr. Armitage thinking, “Yikes, now she has that ignoble plant in two places!”

Passing from a huge plant to one that is comparatively diminutive, I’m having a lot of pleasure watching a little Japanese fan-leaved columbine (Aquilegia flabellata, Zone 4). This is a small (8 to 10 inches/20 to 25 cm tall), semi-dwarf columbine with attractive fan-shaped foliage of good substance. The leaves are thicker and wider than other columbines, with a blue-green colour. Several plants clustered in a group would be an eye-catching display at the front of a border or to the side of steps. My plant blooms earlier than other columbines, with bluish white flowers topped with prominent horns. There is a named cultivar (‘Ministar’, with blue sepals and white petals) and several varieties combining mauve and white. My plant usually has one or two seedlings close by (far fewer than typical columbine seed production) and I always let them grow. But now I realize what a good display it would make to have three or four plants grouped together, and I’ll be looking for a few more pots this season. (They can also be grown from seed.)

My simplified weeding strategy

It seems I’m always whining about weeds. My garden once was an apple orchard, and it has a long weed history and many millions of weed seeds banked in the soil. I have dug myself silly trying to get the roots out, but no matter how much root material I remove, the weeds just keep on coming. Of course, there’s a clear message here: the plants are more resilient than the gardener, and I’m starting to get the point. They were here first, and longest.

Here is my plan for this year. If the weed has a taproot (like dandelion) or a shallow tuft of roots (like plantain), I’ll dig these out until my resources of time and energy are exhausted. But for weeds with deeply buried running roots, like thistles and creeping bellflower (Campanula rapunculoides), my past digging efforts have been entirely useless. Instead, I’ll reach a compromise with these persistent, indigenous plants, and simply pull up the stems as they head up with flowers. I’ll take pleasure in that satisfying “pop” as the stem detaches from its root, knowing that I’ve set its seed-making efforts back for several weeks before it tries to make flowers again. Certainly it will be spreading underground, but I hope to be forcefully obstructive in preventing any flowers from appearing. It will probably take three sweeps of the garden through the season to keep these weeds from flowering. And if this doesn’t work, I’m giving up and letting them have the place.

Water, water everywhere

The rain this month has been truly impressive. My garden already has the lush fullness of August, and it’s barely June. This amount of moisture certainly promotes growth, but it also influences the proliferation of disease organisms and garden pests.

I’ve noticed that some Japanese maples are showing crisp and curling leaf edges, a sign of possible fungus infection. Foliar infections won’t permanently damage the tree, and eventually drier weather will stop the spread of disease. A more serious problem for these trees is soil-borne verticillium wilt, which proliferates in water-saturated soils and acts to block the vascular system within woody trunks and branches. When leaves on an entire branch of a Japanese maple suddenly wilt and the wood appears dead, verticillium wilt may be the cause. There’s not much to do about this, except try to increase drainage around the tree by digging in sharp builder’s sand, and fertilizing with bloodmeal (lightly scratched in over the roots) to encourage more growth.

Ground crawling pests like earwigs, slugs and snails also benefit from all the rain, and I certainly expect to see lots of green aphids on the roses. It’s time to be thinking of the various traps and techniques gardeners employ to ward off the chewing and sucking hordes. However, it just might be best to remain calm and find the silver lining. This should be a bountiful season for newly hatched fledgling birds, with plenty of fat and juicy bugs to eat!

Thanks for stopping by Making a Garden.

 

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2 thoughts on “Rodgersia’s leaves of distinction”

  1. Hi Jeff (June7),

    Nice to hear from you, and thanks for the information. I’m pleased to know Astilboides tabularis can take deeper cold, to Zone 4 (and maybe lower). I suspected that was the case, but couldn’t find any printed references to the low zone. Yes, a really intriguing plant! And I know it’s available out at Mason House Gardens in Claremont, Ont.

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  2. Great article Judith. Astilboides is a great plant but is much hardier than noted. Zone 4 at least and perhaps even colder.

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