Like people, garden plants have their share of bad habits and weak points. Certain perennials especially can be invasive or floppy, fussy about food, messy at some stage or prone to ailments. The perfect plant is a rare breed indeed, but as a group, meadow rues (Thalictrum spp.) come mighty close. Lovely of leaf and delicate in their flowering, they combine graceful habits with a sturdy constitution. Craving no more garden space than you allot, meadow rues make few demands on a gardener's time and energy.
Grown well, they'll lend their understated presence to any garden not entirely windswept, parched or starved of nutrients. Where the soil is reasonably fertile and holds some moisture, meadow rues thrive in sun but are equally at home in flickering shade. From mid-May to August the various species and cultivars follow each other in bloom.
Without exception, the foliage of these garden stalwarts is every bit as significant as their flowers. Out of bloom, they maintain a leafy show as fine as any in the garden; indeed, according to the 1930s garden writer Louise Wilder, their foliage is "uniformly beautiful" and "their chief fortune." The more my partner, John Scanlan, and I grow these elegant perennials, the more we appreciate their gentle shades and refined ways.
Around the globe, upward of 120 species of Thalictrum grow wild, and 10 or so are native to Canada. Among them, in order of appearance, are early meadow rue (T. dioicum), skunk meadow rue (T. revolutum) and purple meadow rue (T. dasycarpum). Though seldom abundant, their cut leaves and small fluffy flowers are easy enough to spot in woods, damp thickets and, of course, meadows.
Although most meadow rues are said to be hardy to Zone 5, all those mentioned here thrive in our Zone 4b garden. Earliest to bloom for us, from mid-May to early June (tulip time in our area) is the cultivar 'Thundercloud' (T. aquilegiifolium 'Thundercloud'). At a height of 60 to 75 centimetres, it's also the shortest we grow (although I've heard of it reaching up to 1.25 metres). As with several other meadow rue cultivars, its so-called flowers are really tufts of fluffy stamens, dark purplish red in this case. Massed above foliage resembling a blue-green maidenhair fern, 'Thundercloud' has the soft, misty effect characteristic of meadow rues. This is a plant for a damp but well-draining corner of a sunny rock garden or bed, or the front of a lightly shaded border. In sun, a group of late tulips-pale yellow, purple or dark plum-could rise behind and through, while in shade, lungworts, hellebores or Japanese primroses (Primula japonica) would be fine company. Best grown in groups of three or more, this scaled-down meadow rue is easy to propagate by division just as growth resumes in spring.