Most gardeners complain about weeds. It’s been said that there are no weeds, only plants in the wrong places. There may be something to that. Take the dandelion in the image at the top of the post. It’s been in that spot for several years. I cut out the flowers that have bloomed to keep them from producing seeds and otherwise leave it be. It’s sort of like keeping a wild animal as a pet.

More seriously weedy are several plants I would never have introduced to this garden now that I’ve come to know them. Once established, they spread and colonize, often invading other plants to the point both have to be dug up in order to remove the invader.
Two I’m doing battle with right now are Italian arum and periwinkle (Vinca minor, two different varieties). I planted them because they were praised and recommended by reputable garden writers.
The late Henry Mitchell was keen on the Italian arum (Arum italicum), and since he was a good writer, I was infected with his enthusiasm for the plant. Okay, my original specimen was grown from seeds I collected near a bike path, so maybe it’s an unruly type. Mitchell, I recall, mentioned a variety called “Marmoratum,” which apparently was granted an Award of Garden Merit by the Royal Horticultural Society.
I would like to bestow an Invasive Plant Curse on the arum, because it has made itself a pest here. It spreads both by seeds — which are one of its most attractive features — and underground bulblets. The older the plant, the deeper it roots, making it almost impossible to remove without major digging and disruption. And its flowers are unremarkable, apart from smelling like rotting meat (a quality common to the arum family).

So, Mr. Mitchell, were you aware of these problems with the arum and chose not to reveal them, or was yours better-behaved?
A plant with similar faults is the bluebell (Hyacinthoides non-scripta or H. hispanica or maybe a hybrid of the two, H. × massartiana). It’s the much-praised denizen of the springtime woodland. I didn’t plant them; they were already established when I started gardening here. In bloom, it’s quite pretty, but it spreads even faster than the arum, and like it has lush, dense foliage that weighs down or shades any smaller plants nearby. Both bluebells and arum go dormant for the summer, but in spring, where these plants grow thickly, others get shaded or crowded out.

The bulbs of arums and bluebells are a foot or more below the soil surface, so digging them out is a challenge. In spots where they’ve wedged themselves in among other plants, it means major disturbance. The optimal times for transplanting or dividing perennials and bulbs vary, so one is bound to be doing this operation at non-optimal times for some things. Besides, in my garden it’s tough, unpleasant work, because there will inevitably be tree roots to deal with.
I’m going to experiment with cutting off the top growth of arums and bluebells in specific areas. In theory, this will eventually do them in.
Periwinkle is often recommended as a groundcover for “problem areas” such as dry shade. That’s why I planted it here. Unfortunately, I chose the unimproved basic type of Vinca minor. It has covered the ground altogether too well. It’s evergreen, so few other herbaceous plants can compete with a thick mat of it. Even the yellow and green variegated type has revved up in recent years and wound its way around irises and other perennials.

Fortunately, periwinkle can be uprooted quite easily, working from the edge of a patch inward to the more established parts. It pays to keep an eye out for a resurgence, though. Missed bits or roots that haven’t been extracted will make a comeback.
Forget-me-not (Myosotis) is another of my self-inflicted weeds. It’s a case of too much of a good thing. In full spring bloom, it creates a blue mist of tiny flowers. What’s not to love? Its habit of abundant self-seeding, that’s what. The dense crop of seedlings that results can out-compete less aggressive plants. Individual plants are short-lived and easy to pull up, but it’s important to remove most of them as soon as bloom starts to fade, leaving only a few to develop seeds.

Random self-seeding is also responsible for a surprisingly large number of unintended hellebores in some of my beds and borders. Now, I like hellebores, and they do well here, but I don’t want them in the wrong places (they are fair-sized plants with “presence”) or glommed up against other plants that need their fair share of space, nutrients, and water. Moreover, not all of the volunteers have attractive blooms; some of them are murky mixtures of purple and green. Which means I’m going to dig some of them up and send them to the big compost heap in the sky.
The difference between a garden and plants growing in a state of nature is that the latter is a winner-take-all brawl and the garden has a referee — the weary gardener, who decides what is a weed and what isn’t.
