Mediterranean Spurge

Peculiar bloom tops handsomely colorful foliage.

Seed for this species is all or nothing. The straight species of Mediterranean spurge, Euphorbia characias, seeds abundantly. It can actually be a bit too prolific. However, fancier and extensively bred cultivars either produce no viable seed, or produce only a few seed that are not true to type. Such seed grows into plants that resemble their ancestral species more than their direct parents.

Foliage of common Mediterranean spurge is slightly grayish green. Cultivars exhibit more distinctly grayish, bluish, yellowish or variegated foliage. Appealingly weird and generally greenish floral trusses bloom on top of upwardly arching stems about now. Mature plants are less than four feet tall and broad, with neatly rounded form. They slowly lean toward sunlight as they grow and bloom.

After old stems get cut to the ground in autumn, new stems develop through winter, to repeat the process. Established plants are surprisingly resilient to harsh exposure, warmth, wind and lapses of irrigation. They just dislike shade and constant dampness. However, even the healthiest live for only five to eight years. Those that toss seed can provide their own replacements before they go.

Dead Nettle

Dead nettle has lively silvery foliage.

Because its common name is so unappealing, dead nettle is more commonly known by its Latin name, Lamium. or more specifically, Lamium maculata. It is a low and subdued plant with pastel pink, lavender or white blooms, and small deep green leaves. However, modern garden varieties have silvery variegated foliage that brightens shady spots. Some are yellowish green.

The herbaceous stems spread only one or two feet at first, but then root into the soil where they land, and continue to spread some more. The mounding growth can get about half a foot deep, or a bit deeper where it can pile up on other plants or rocks. After late spring or early summer bloom, deteriorating flower stems should be shorn back to enhance density of foliar growth below.

Stems that begin to spread a bit too far into areas where they are not wanted can be left long enough to develop roots through spring, and then pulled up and planted where they are wanted. Even before they spread that much, no one would miss a few rooted stems discretely taken from established plants to make copies. Plants in sunnier spots want richer soil and more water.

Variegated Foliage Brightens Shady Spots

Variegation contrasts nicely with dark green.

Up at high elevations and out in deserts, where sunlight is most intense, plants can actually get more exposure than they need. The bluish or grayish glaucous foliage of the Colorado blue spruce from the Rocky Mountains, and the century plant from the Sonoran Desert, is actually designed to reflect a bit of sunlight so that the foliage does not scald.

Plants from foggy coastal areas, and understory plants that naturally live below the canopies of larger trees, do the opposite. They are deep green to absorb as much sunlight as possible. This is why Monterey pine and Monterey cypress are the same shade of dark green; and why most ferns are such dark green. Only tree ferns that stand above lower plants are naturally light green.

This can make it difficult to brighten a dark spot in the garden, since most lightly colored foliage wants an abundance of sunlight. White or lightly colored flowers would theoretically work nicely, but generally are neither permanent nor abundant where shaded. Golden foliage, like that of golden elderberries, golden arborvitaes and golden junipers, is greener in the shade.

Variegated foliage is different. Even if the green parts of the foliage are greener where well exposed than where shaded, the variegated parts are always variegated. Some plants are variegated with white. A few are variegated with yellow. Those that tolerate shade can brighten shaded spots nicely, or at least add a bit of contrast to dark green.

Even if the big pastel flowers of variegated angel’s trumpets and variegated hydrangeas do not stand out as well as they would against deeper green foliage, the foliage provides its own contrast. A concern with hydrangeas, as well as variegated dogwoods, is that they are deciduous, so lack foliage through winter.

Variegated Pittosporum tobira and variegated euonymus have smaller evergreen leaves. Variegated ivies are nice ground covers. On a smaller scale, so is dead nettle. Euonymus, pittosporums and ivies will sometimes need to have more vigorous unvariegated stems pruned out before they overwhelm and replace variegated growth.


Polka Dot Plant

Polka dot plant is mostly pink.

Of all the tender perennials, polka dot plant, Hypoestes phyllostachya, is one of the lesser likely to survive winter outside, even if sheltered from the cold. Yet, it is actually becoming more popular as a warm season folliage plant for pots of small mixed perennials. It is a delightful small houseplant, either alone or as an understory plant to larger houseplants like ficus. As an understory plant, It is easier to work with if grown separately in small pots that can get nestled into moss on top of the soil of the larger plants. If it has a problem, it can easily be replaced or removed.

The foliage typically has so many pink spots that less than half of the foliar surface area is green. Some have white or darker reddish pink spots. The bloom is not as interesting as the foliage, and is not often seen. Roots like rich and evenly moist potting soil. The biggest plants are not much more than a foot high. Most stay less than half as tall. New plants are easy to propagate from cuttings. When things get warmer in spring, plants that have more stems than foliage can be cut back to regenerate.

Six on Saturday: No Silver


We have bronze, and we have gold, but we have no silver, at least not in these six pictures. I suppose I could have posted a picture of Eucalyptus cinerea or Echeveria glauca. I thought it would be more interesting to contrast two different cultivars of each of these three species. Only two are truly bronze. Only one is truly gold. They contrast nicely anyway.

1. Bronze smoke tree – Cotinus goggygria – Modern cultivars with richer color like this are now considered to be ‘purple’. When I studied it in the 1980s, the old fashioned bronze cultivars were still available.P90713

2. Gold smoke tree – These might not have been available back in the 1980s. I do not remember every seeing one. I am not often impressed with their vigor; but I have seen them doing quite well in some situations.P90713+

3. Bronze canna – Canna spp. – I believe this is the cultivar ‘Wyoming’, with bronze foliage and rich orange bloom. The bronze color does not show up well here. Other cultivars are much darker purplish bronze.P90713++

4. Gold canna – Just as the bronze cannna is more bronze than it looks here, this one is more golden, particularly when the foliage is new. Obviously, it is variegated as well. The foliage is as interesting as the bloom.P90713+++

5. Bronze New Zealand flax – Phormium tenax – It might be known by a cultivar name rather than the species name of ‘tenax‘ followed by a cultivar name. Weird modern hybridization complicates nomenclature.P90713++++

6. Gold New Zealand flax – I really though that this one was ‘Yellow Wave’, but it does not look like that here. The variegation is more white than yellow. Could this variegation instead be classified as silvery?P90713+++++

This is the link for Six on Saturday, for anyone else who would like to participate:

Mirror Plant

90227Classic but simple mirror plant, Coprosma X kirkii, was a utilitarian shrubby ground cover for many years before all the colorful modern cultivars that are so popular now were invented. Individual plants can cover quite a bit of ground without getting any deeper than two feet. It is particularly useful in coastal landscapes, because it is so resilient to wind and exposure, as well as sandy soil.

Modern cultivars are remarkably variable. Some are variegated with white, yellow or bronze, either as foliar margins or blotches. Others are very dark purplish bronze. One cultivar is dark bronze with pink foliar margins. Most of these modern cultivars have nicely rounded and undulate leaves, although some have narrow leaves that are comparable to those of the now rare original cultivar.

The more colorful modern cultivars do not grow quite as large or as efficiently as the original, so are not quite as practical as ground cover on large areas. However, they should work just as well for smaller areas, and are even better in conjunction with other plants. Some types of mirror plant are shrubbier. Yet, others cascade nicely from terraces and big planters, and over retaining walls.

Different Time Zones

P80901KIf the flower on the left is a four o’clock, is the flower on the right a five o’clock, or perhaps a three o’clock? Is one a.m. and the other p.m.? What about the flower of the same species that I featured twelve hours ago? What about those in another picture that I will share next Saturday?
Of course, only the colors are different; not the name . . . or the time.
What is odd about these two seemingly different flowers is that they are on the same plant. In fact, they are on the same stem, separated only by a few inches.
Four o’clocks can be odd that way. Individual plants typically bloom with exclusively pink, red, white, yellow or orange flowers. The shades and hues of these colors are variable, but are typically homogeneous throughout each entire plant.
Some plants bloom with flowers of one color that are spotted or variably striped with another. Their flowers are not as homogeneous as those that bloom with only one color, so some of their flowers might be uniformly one color or the other, without spots or stripes. Some plants bloom with a few different colors!
Distinctly bright pink (but not light pink) flowers seem to be the most fragrant and the least variable, typically devoid of spotting or striping. They may be more closely related to the wild species, as it would have been found in its natural range in the Andes, prior to breeding for more interesting colors. Perhaps, after enough generations, other four o’clocks would eventually revert to the same characteristically fragrant bright pink flowers, just like many varieties of nasturtium eventually revert to standard bright orange and yellow. It is hard to say now, while naturalized four o’clocks have yet to do so.