Seedy invasives

In my “More plant families” posting yesterday, I turned to two big families I’d missed in an earlier posting and then to my recollections of plants in my Columbus OH garden that were self-seeding and/or self-hybridizing: cleomes, California poppies, opium poppies, foxgloves, borage, columbines, tradescantia, nasturtiums, and then I looked at the plant families they belonged to — a project that added 8 more families to the 9 I’d looked at in the earlier posting and the two I’d looked at in my “Penstemon” posting. (If you’re counting families, the score is now 19.)

Now I want to switch my focus from the intricacies of botanical taxonomy (without abandoning the topic entirely) to the significance of self-seeding (or self-sowing), one form of invasiveness in the gardening world, one way in which plants can spread so as to take over parts of a garden. The other is vegetative spread, by division or, especially, by creeping (via underground roots or surface runners). You’ve got your seedy invasives and you’ve got your creepy invasives.

Of course, the topic goes well beyond these homey horticultural matters, to invasive plants — and animals — on a much larger scale, where invasiveness has taken on political significance of several kinds. Eventually I intend to post about a piece by Andrew Cockburn in the September 2015 Harper’s, “Weed Whackers: Monsanto, glyphosphate, and the war on invasive species”.

Some time ago, I contemplated writing a book on Gardening with Invasive Plants, describing my own experiences (including some less than happy ones as well as the triumphs). I started with a 1991 posting to the newsgroup soc.motss, which I edited lightly for a 2010 posting “Our Gardens, Our Selves” on AZBlogX (though there’s virtually no sex in it). In the interim, my man Jacques’s medical conditions ran downhill; in 1998 I sold the house in Columbus (and forever left the garden described in the 1991 posting) and Jacques and I moved permanently to Palo Alto and he entered a local dementia care facility, where he died in 2003.

The sense of invasive plant in this material is a straightforward one, embodying a metaphorical extension of the verb invade (and the derived noun invasion and adjective invasive) into a non-military domain. From NOAD2 for invasive:

(especially of plants or a disease) tending to spread prolifically and undesirably or harmfully.

(There are other extensions for other sorts of intrusions:

– (especially of an action or sensation) tending to intrude on a person’s thoughts or privacy: the sound of the piano was invasive.

– (of medical procedures) involving the introduction of instruments or other objects into the body or body cavities: minimally invasive surgery.)

From the 2010 [1991] posting, on two types of plants in our Columbus garden:

plants that stretch out rooting stems above ground or lateral roots below: lamiums of purple, white, buttercup yellow [Lamiastrum galeobdolon aka ‘Yellow Archangel’], anthemis, black-eyed susans, sweet woodruff, the thymes, creeping-potentilla/cinquefoil, barren strawberries, ajuga, coreopsis, germander, lamb’s ears, Chinese lanterns, perennial ageratum, sedums, bishop’s weed, pennyroyal, obedient plant, creeping phlox

plants that broadcast seed and return each year in a new incarnation: columbines, zebrina hollyhocks, the cleomes, dill, larkspur, borage, white valerian, portulacas, wild cinquefoil

I’ll post on the creepy invasives later. This posting continues my earlier interest in the seedy invasives. The ones boldfaced in the list above were covered in yesterday’s posting (as were five plants not on that list — two poppies, foxgloves, tradescantia, and nasturtiums. On to the others.

Zebrina hollyhocks. A very attractive mallow (that is, in the Malvaceae), covered, with a photo and with information about the plant and its family, in my posting on “Abutilon and its relatives”.

Dill. Although this culinary herb has come up a number of times on this blog, I seem not to have posted on it specifically. From Wikipedia:

Dill (Anethum graveolens) is an annual herb in the celery family Apiaceae [the umbellifers, already covered here]. It is the sole species of the genus Anethum…. “Dill” is a Germanic word whose origin is unknown. [Anethum has the same source as anise.]

The plant in flower:


Then fresh green dill weed:


(It’s available dried, but it’s much better fresh.)

And then the seeds:


Dill, either as dill weed or seeds, has many many culinary uses in eastern and northern European cuisines, and also in South Asian, East Asian, and Middle Eastern cuisines.

I’m dwelling on dill so much because I’m so fond of it. In dill pickles —


and in cucumber salads of several kinds, for instance Greek cucumber-dill yoghurt salad:


and in dilled shrimp salad —


(Ok, I’ll stop now.)

Oh yes, some sites warn about the invasiveness of dill.

Larkspur. From Wikipedia:

Delphinium is a genus of about 300 species of perennial flowering plants in the family Ranunculaceae, native throughout the Northern Hemisphere and also on the high mountains of tropical Africa.

… The name “delphinium” derives from the Latin for “dolphin”, referring to the shape of the nectary. [The name “larkspur” is an obvious reference to the spurred flowers; how the larks got into it, I’m not sure.]

All members of the Delphinium genus are toxic to humans and livestock. The common name “larkspur” is shared between perennial Delphinium species and annual species of the genus Consolida.

Now we’re into taxonomic murkiness. The Wikipedia article distinguishes Delphinium vs. Consolida as perennial vs. annual, in which case the flowers I gew in Ohio were Consolida:


But some plant firms list the garden annuals as Delphinium consolida. So: either Delphinium or very close.

White valerian. We start with

Centranthus ruber [Latin ruber ‘red ruddy’], also called red valerian, spur valerian, kiss-me-quick, fox’s brush, and Jupiter’s beard, …. a popular garden plant grown for its ornamental flowers. It grows as a perennial plant, usually as a subshrub though it can take any form from a herb to a shrub depending on conditions (Wikipedia link)


The plant is in the Caprifoliaceae. From Wikipedia:

The Caprifoliaceae or honeysuckle family [Lonicera caprifolium ‘honeysuckle’] are a clade of dicotyledonous flowering plants consisting of about 860 species in 42 genera, with a nearly cosmopolitan distribution.

… They are mostly shrubs [Weigela, Abelia , Kolkwitzia / beautybush] and vines [honeysuckle], rarely herbs, including some ornamental garden plants [Scabiosa / scabious or pincushion flower, Centranthus] in temperate regions… The flowers are tubular, funnel-shaped or bell-like, usually with five outward spreading lobes or points, and are often fragrant.

(Formerly classified in the Valerianaceae, the valerian family, which is now considered part of the Caprifoliaceae.)

But now it turns out that there’s a white variant of C. ruber (despite the ruber; well, these are just names, after all, not definitions), and the white valerian (which is what we grew in Ohio) is a liberal self-sower.


To keep up the nomenclatural complexity, there’s also flower called valerian: Valeriana officinalis, in the Caprifoliaceae of course:

… a perennial flowering plant, with heads of sweetly scented pink or white flowers that bloom in the summer. Valerian flower extracts were used as a perfume in the 16th century. (Wikipedia link)

And, sticking within in the family, a very different plant named Valerianella locusta, known as corn salad or mâche (or a number of other things), an annual salad green, discussed (and pictured) in my posting “More gay greens”. We did grow mâche, but it had a very short season once Ohio’s weather got hot — definitely a cool-season crop — and certain never self-seeded.

Portulacas. Much less complicated are the Portulacas, discussed (and pictured) in my posting here on the genus. In Ohio, both P. oleracerae (the weed purslane, which serves as a salad green) and P. grandiflora, the moss rose. They’re in a small family:

The Portulacaceae are a family of flowering plants, comprising about 20 genera with about 500 species, ranging from herbaceous plants to shrubs. The family … is also known as the purslane family. (Wikipedia link)

Wild cinquefoil. Finally, to a seedy invasive plant that is very closely related to creepy invasives, in the genus Potentilla, the cinquefoils; there are also straightforward woody shrubs in the genus.

The plant, Potentilla norvegica, we knew simply as “wild cinquefoil”, but an Ohio weed site labels it as “rough cinquefoil”:


Rough cinquefoil behaves as either an annual if growing in cultivated ground, a biennial when growing in less disturbed sites, or a short-lived perennial.

It grows as a rosette at the beginning of the season, but later forms an upright, hairy, robust stem with yellow flowers. Leaves consist of 3 coarsely-toothed, hairy leaflets. Rough cinquefoil reproduces by seeds.

Oh my, does it!

On the genus, from Wikipedia:

Potentilla … is a genus containing over 300 species of annual, biennial and perennial herbaceous flowering plants in the rose family, Rosaceae. They are usually called cinquefoils in English. Potentilla are generally only found throughout the northern continents of the world (holarctic)

… Typical cinquefoils look most similar to strawberries, but differ in usually having dry, inedible fruit (hence the name “barren strawberry” for some species). Many cinquefoil species have palmate leaves… The [characteristically 5-petaled] flowers are usually yellow, but may be white, pinkish or red.

I’ll get to the creeping cinquefoils in a later posting. Here I’ll put in a word for the shrubby species, which I’m fond of. From the Gardening Know How site:

Bright yellow flowers cover shrubby cinquefoil (Potentilla fruticosa) from early June until fall. The shrub grows only 1 to 3 feet tall, but what it lacks in size it makes up in ornamental impact.

Although the species shrubs produce single yellow flowers, you’ll find many cultivars with color variations [white, orange, pink, bicolor red/orange] and some with double flowers.


(Family count: 3 not in previous plant-family postings, for a total so far of 22.)

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