This innocent tendril will one day strangle my neighbor's ficus.

I’m really more of a boxwood person, but I must admit a certain nostalgic delight when I see old-growth ivy. And by ivy I am speaking of English Ivy, of the Hedera family. This is important; most of what we see in this country, though commonly referred to as Boston Ivy, is in reality closely related to the grape vine—a different type of creeper altogether. In fact, and I’m sure to put some backs up when I say this, Wrigley Field’s luxuriously green outfield wall isn’t, if we want to be precise, “ivy-covered.” It’s covered in a pleasant mixture of Boston and Japanese Bittersweet. And I can’t speak for each institution comprising the Ivy League, but I imagine much of the building foliage is of the Boston rather than the English variety. One might just assume the “creeping-grape-vine league” didn’t quite have the same cache.

Nostalgia aside, Boston Ivy (of University and outfield fame) is the far handsomer species, with its broad, waxy leaves that ripen to majestic hues as the season turns. Boston Ivy uses gentle suckers to quickly establish itself, and can be trained and cut back with ease. It is decorative and almost geometric when allowed to flourish, and can be a pleasure to propagate.

Evergreen: Hedera can weather even harsh winters.

By contrast, the English stuff (Hedera) is far woodier, with smaller, tougher leaves, usually outlined in cream, and punctuated by the occasional cluster of mildly toxic berries. It chooses to climb in the cruelest way a creeper can; Hedera forces its tendrils into the crevices of structures, or trees, or fences, or whatever meekly shares its space, swelling each to gain its purchase. Once established, it coils itself tightly with little regard for its host. Mighty, 200-year old oaks succumb to Hedera by way of a five-year strangulation. Given time, Hedera will peel the roof from a house. It is the ivy that will cover the planet after we are gone.

Hedera is also the ivy of my childhood, when I spent summers tramping through Wepre Wood, in Flintshire, Wales. This is a medieval wood, with cold, running brooks, and deep, unfound creases. There is a 13th century castle, and a modest waterfall said to be haunted by a murdered nun. And everywhere ivy: roots with the girth of tree trunks, impenetrable thickets obscuring the geography, and groping new growth, blindly searching every rock face. In one favorite spot the ivy ran in a tangled mass up a sheer dirt bank, enticing my cousins and me to use its sinuous offshoots to pull ourselves to the top. There it would thin out, desultory, blanketing a clearing, and for a moment, appear harmless. But I knew better; it was both lord and tenant of those old woods, and had been for a thousand years. When those summers would end, and it would suddenly be time to return to the States, I would desperately consider hiding a cutting in my backpack. I imagined it would sprout, and soon spread, lending its wildness to the tame and immature woods behind our house.

And this is the point really about English ivy. It possesses an implied longevity that we all recognize, and some of us admire. The oldest, gnarliest specimens suggest time has passed not in years, but over generations. When it has overrun a structure, thickly matting the architecture, it can be thoroughly transformative. No longer do we see a building that has been erected and then covered. Instead we encounter something that has risen from the earth, pulling the ground cover with it, and through unknown mantle forces, has established itself in a field.

Growing it though is another matter entirely. If it takes hold it will most certainly kill something, and if denied that pleasure, it will find a fence to dismember or a perfectly good shed to warp. Of course, if these things don’t bother you, then there is really no substitute for suggesting permanence. I bought a few pots of it several summers back with just this idea in mind—an ugly, barren wall needed cover. It died within nine months. And with that passing I had learned two more lessons of this ancient species. One, hedera needs something to crush or strangle. Give it a trellis at the very least. Secondly, do not buy hedera. Instead, find the oldest hedera-covered building in your area, and when no one is looking, relieve it of a cutting. Hedera is an unruly thing, and somehow it seems to appreciate when its benefactor is also willing to run a little wild.