All of the three spurge varieties in the garden are confounding, but for varying reasons. The most useful of the three, Robb’s spurge (Euphorbia amygdaloides subsp. robbiae, below) covers substantial territory in difficult, dry shade with surface roots of maples and tulip poplars that leave little room for digging. Little else grows in this area, and how could it with the root competition, but Robb’s flourishes until it becomes a dense cover. Then oddly, it subsides for a few years before once again growing with renewed vigor. But while one area wanes, another flourishes.
Cypress spurge (Euphorbia cyparissias, below) is reputed to be quite aggressive, but the fine leafed spreader has had its troubles in the garden. Over two years, seedlings of a dark leafed geranium, (Geranium maculatum ‘Espresso’) planted for color contrast, vanquished a vigorous patch of cypress spurge that I presumed had been constrained only by large stones. The spurge didn’t even put up a good fight to a geranium with seedlings that are easily plucked if they pop up in the wrong place. Certainly, cypress spurge must be a problem in somebody’s garden, but not here, and it is quite attractive, even after flowering. The few clumps that remain battle roots of a Japanese maple, and hopefully it gains a bit more vigor to fill this small space.
Happily, seedlings of the dark leafed ‘Bonfire’ spurge (Euphorbia polychroma ‘Bonfire’, below) regularly appear in partially shaded areas, but just as regularly they disappear in dry areas of the garden. Since no part of the garden is irrigated, ‘Bonfire’ comes and goes, adding a dash of red foliage, but unfortunately the wisps never amount to much.