Teosinte as an Ornamental

Modern corn, Zea mays ssp. mays, is considered to be derived from Zea mays ssp, parviglumis, a wild grass native to southern Mexico. About 9000 years ago, early farmers' generations of selective seed-saving finally resulted in something resembling modern maize. The rest is history-- the crop became the staple of Mesoamerican empires, fed European mouths after the Spanish conquest (or Spanish-Aztec War, if you prefer), and serves humankind today as the critical constituent of tortilla chips and a certain motor fuel additive.

Teosinte as a pseudo-ornamental. Its vigor was, perhaps, underestimated.

But what business has a 21st-century gardener in growing the ancient parviglumis? First, considering the grain as a potential food source: the hard exterior case surrounding the kernel necessitates a good bit of processing, and the yield, is, of course, quite small. John Doebley and his lab have written excellent articles on teosinte here; addressing teosinte's use as a food crop, Doebley writes of one of his experiments, "The yield [of edible grain] over all of my plot was 467 kg/ hectare." One survey of farms in 16 nations, with yield data from 2013, reports average corn yield as 7239 kg/ hectare-- rendering the yield of teosinte simply pitiful by comparison (Lunik & Langemeier). This is a bit unfair, though-- pitting a wild grass against some of the most heavily-modified plants in agriculture-- so Doebley notes that teosinte's yield is "is not too far off yields of 1000 to 2000 kg/hectare of early US open pollinated maize varieties (Troyer and Mascia 1999)." On the whole, though, no person should plant teosinte expecting any substantial amount of grain in return. 

"Teosinte ear (Zea mays ssp mexicana) on the left, maize ear on the right, and ear of their F1 hybrid in the center." Photograph and caption by John Doebley; used with permission.

Corn is not very high on any list of ornamental plants. But I can think of two cultivar groups that are used ornamentally-- the multi-colored "Indian corn" often sold as an autumn decoration, and the two or three varieties of variegated corn sold by specialty seed purveyors (the ornamental variegation being that of the leaves). Both maintain the general habit of modern maize, however-- a single tall stalk. This is advantageous for densely-planted fields, but in the wild, natural selection would never favor such an uncompromisingly compact, bolt-upright architecture. Teosinte emerges as modern corn does, with a single leader shoot, but eventually issues side shoots from the base, resulting in much fuller grassy clump than would otherwise be expected from corn-- and ornamentally speaking, a nice clump is preferable to a tall, ramrod-straight stem.

Secondary growths begin to emerge from the base of teosinte.

"Zea mays ssp. parviglumis plants growing in a ravine near Teloloapan in the Balsas river drainage, Guererro, Mexico." Photo by Hugh Iltis, caption by John Doebley. The tassels look quite nice here-- the lanky base is mercifully clothed in foliage. Maybe there's some potential...

Is teosinte passable as an ornamental, then? No doubt most would consider it more ornamental than modern corn-- but that is a pretty low standard, admittedly. The average gardener, I expect, would declare it to resemble an untidy and unproductive patch of corn, curiously located in a flower bed rather than in a vegetable garden. The novelty of having such a historic plant-- one quite central to agriculture, genetically speaking, yet obscure in itself-- makes it worth having, in my view, even when it looks like johnson grass that's invaded the rose border. Hopefully, when day length shortens, my own patch will oblige me with flowers and seed.

Rosa carolina and Some Hybrids

Much of my rose-collecting has been centered around Rosa carolina and its first-generation hybrids-- exactly why, I'm not sure, but there are some factors that might account for why I find this species so attractive...

• It has a relatively short stature;
• It suckers-- effectively propagating itself;
• The glandular flower buds with long stamens are neat;
• It's easy to breed with.

Being native to the Southeast disease is almost never a concern, and it can tolerate significantly more neglect and shade than the complex Chinensis-section hybrids. And the once-blooming habit has never bothered me too much-- after all, the extreme vast majority of other native plants flower once annually.

There is a smidgeon of phenotypic variation out there: the Guide to the Vascular Plants of Tennessee recognizes two subspecies, one, subserrulata, having eglandular flower parts, and ssp. carolina having the characteristic array of pedicel and hypanthia glands. Petal width, flower size and color, and leaf size, color, luster, and degree of corrugation vary too, of course.

R. carolina is widespread in Middle Tennessee cedar glades, in particularly rocky locations made to adopt a relatively small thicket form. These flowers are very pale pink, probably having been bleached white by intense sun.

A Jackson, MS plant with smallish flowers and narrow petals

A Jackson, MS clone with relatively narrow petals-- and are those stable "dimples" at the petal edge or just evidence of herbivory?

A Middle Tennessee plant of darker coloration

Relatively wide petals of an Oxford, MS clone

As with nearly every other rose species, the mutation creating the white alba variety has no doubt occurred countless times-- at some point white R. carolina was in commerce in North America, but currently no nursery offers it, although it is still apparently sold in Europe. And the mutation of some stamens into petals has given rise to the double form plena (which does not seem to be available either).

Fortunately this species has garnered the attention of some amateur breeders who were kind enough to share some suckers with me-- one of my favorites is '3/4 Native' from the writer of Mid-Atlantic Plant Research Center, Tom Silvers; the mother being a cross between the hybrid tea 'Fragrant Cloud' and R. carolina, and the pollen donor being R. virginiana (closely related to carolina, in the same section of the genus). Although the possibility for disease is certainly there, owing to the admittedly somewhat unhealthy hybrid tea heritage, it has proved to be quite resistant for me, even in very humid conditions.

Double but with a glimpse of stamens, '3/4 Native' is almost the ideal result from its parents-- the extra petals, saturated color, and foliage pigmentation from the Chinensis-based hybrid tea, with the wild habit and resilience of the Carolinae natives.

Another hybrid, of the parentage R. carolina X ('Red Dawn' X 'Suzanne') is a cull from Rose Hybridizers Association forum member J. Bergeson. It has interesting cupped semidouble flowers and an attractive arching form, but had some trouble with blackspot, and resembled R. carolina much less than other hybrids I've had.

Quite pretty-- but sadly I don't have it anymore, which might be for the best owing to Southeastern humidity.

The last I'll list here is a cross between R. gallica from Gaul, an important progenitor of many of the roses grown in Europe before the introduction of the repeat-blooming "Stud Chinas," and R. carolina-- uniting the carolinae and gallicinae sections in the most direct way possible. The plant is pretty as all wild roses are, but might be most interesting for what it represents genetically.

Carolina-gallica.

Although few carolina hybrids are commercially available, and many of those currently grown might not actually be the best use of space, if one is looking for roses of maximum ornamental value, the group represents what cultivars might be possible if native plants were used genetically in conjunction with the traditional Old World imports. This might not be the future of moneyed corporate rose breeding, but it certainly has seemed to become the theme among many amateur breeders-- which is certainly a good thing owing to the historical supremacy of hybrid teas and their relatives.

Boursault Rose 'Morletii'

The Boursaults constitute one of the most obscure classes of roses. Bred mostly in France in the Nineteenth Century, they are little more than novelties today, but likely succeeded as niche collector's items back in novelty-obsessed Victorian-era gardening, as their flowers arrive very early in the season, blooming just slightly later than the Banksias (a group of related climbing roses known to flower in conjunction with tulips and hyacinth). 'Morletii" is blooming now in central Mississippi.

'Morletii,' a Boursault from 1883

They are very distinctive in appearance, with violet-colored, totally-thornless wood, soft leaden leaves, and procumbent or climbing habit. They sucker very lightly, and are best grown as short climbers or large, arching shrubs. Traditionally, they are said to descend from Rosa pendulina, or the "Alpine Rose," but it is possible that a case of Nineteenth-Century misidentification occurred, and that they are really the descendants of the North-American Native R. blanda. 

Bred by Morlet (reportedly something of a charlatan) in 1883, the rose in question has semidouble flowers of a rather ragged shape much like crumpled paper, with a paler center marked by golden stamens. The flowers are short lived but the plant provides color for a few weeks in spring, before most other roses have developed flower buds. In my experience, it is quite sterile-- so there aren't any ornamental hips for fall; however, the leaves turn bright red come autumn. It is not much troubled by disease, but can get some black spot in humid climes.

Why grow Boursaults? Admittedly, the best thing this small class has going for it is its obscurity and history. Today they are much outclassed by other roses which are repeat-blooming and more disease-resistant. But I always find something charming and rustic about roses with "informal" (to put it charitably) flower shapes and a scrambly habit; one certainly can't image the likes of 'Knock Out' being as graceful next to a split-rail fence or in a mixed perennial assemblage. So I can safely grant the rose Luddite seal of approval to 'Morletii,' which is still currently sold by Rogue Valley Roses.

The Weedy Introduced Geraniums

I remember that, when I was little, I loved to look at springtime weeds-- especially the introduced annual Geraniums that are the subject of this post-- assigning my own common names to them and trying to find interesting variants. Among these Geraniums there's quite a diversity of leaf shapes, with the "Cutleaf" G. dissectum at one end, the staidly normal-geranium-looking G. pusillum in the middle, and G. molle rounding out the other end with its rotund leaves with little space between the lobes.

G. dissectum. Taller than its brethren, dissectum's flowers are some permutation of saturated carmine pink.

G. pusillum, in pale pink, approaching white.

Note that, as always, my IDs may be imperfect, and there are other introduced annual geranium species of wide distribution.

The flowers are what one would expect, small versions of the "civilized" varieties of cranesbill and the native perennial sorts. I suppose their size is an adaptation to the relatively ephemeral life cycle of these plants, facilitating speedy reproduction while requiring little energy expenditure. Their seed capsules have the classic cranesbill shape.

A blurb on Wikipedia-- without citation-- claims that G. carolinianum tolerates relatively alkaline soil conditions, which could very well be the case, given these plants' predilection to spring up among concrete rubble, gravel, and other limey substrates.

My affection for weeds crops up again-- they might be promiscuous aliens, but I think the introduced annual geraniums are charming.