Polka Dot Plant

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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.

Colorful Foliage Fades Through Summer

P90713Autumn foliar color is not the concern yet. It develops later as deciduous plants defoliate for winter. Purplish, reddish, yellowish, bluish or gray foliar color that can be seen now is provided by plants that are colorful while actively growing. Almost all of this sort of foliage is most colorful when it is young and fresh, early in spring. Then, through summer, some of the best foliar color fades.

This process is perfectly natural. It does not imply that anything was done improperly, or that plants were not given what they need. In fact, most plants with colorful foliage would rather be green. They are mutants that were reproduced specifically for their distinctive color. Some try to revert back to green by producing greener shoots that grow faster because they have more chlorophyll.

Photinia is an odd one. By now, The rich green foliage shows no clue that it was rich reddish bronze when it developed early in spring. The foliage did not really fade. It merely matured. Then there are the newer cultivars of purple leaf plum, which maintain their color from spring to autumn. It is amazing that such darkly colored foliage that seems be devoid of chlorophyll can photosynthesise!

Some plants maintain their color better than others. Gray or bluish foliage is always gray or bluish; but admittedly, blue spruce and blue junipers are not quite as striking now as they were earlier. If red fountain grass and bronze aonium fade, it will be too slight to notice. Stems of bronze, gold or striped cannas that fade after bloom get pruned out in favor of more colorful unbloomed stems.

‘Forest Pansy’ redbud, ‘Summer Chocolate’ silk tree and ‘Sunburst’ honeylocust are notorious for fading. By now, the formerly richly bronzed redbud and silk tree merely seem to be stained with coffee. Golden honeylocust might have been bright yellow in spring, but now just looks sickly. Gold tipped and silver tipped deodar cedars can likewise be a bit pale. Bronze elderberries hold color well, but golden elderberry might now be chartreuse.P90713+

Candy Corn Dog

P90721Just a short distance from the corn dog orchard, I found this candy corn dog growing wild. I really had no idea that candy corn grew in a corn dog form like this. These particular candy corn seem to have turned from green to yellow to orange as they ripened. It will be interesting to see if the outer ends eventually ripen to yellow like conventional candy corn, or if they are a fancier cultivar. They sort of look like tiny persimmons.

Perhaps it is ‘Cupid Corn’, which is red at the outer end and pink in the middle, for Saint Valentine’s Day. If so, it will be quite stale long before next February.

Even if it is ‘Reindeer Corn’, which is red at the outer end and green in the middle, for Christmas, it will not likely be fresh by late December.

Heck, just expecting it to last until Halloween is a stretch. There are actually a few different cultivars for a variety of holidays, so this one could be for any of the obscure holidays before Halloween that few know about; or it could be very out of season.

I do not know how this candy corn dog got here. I did not plant it. I am pleased that snails, slugs, squirrels or insects have not eaten it so far.

Something came into this part of the landscape earlier, and ate all the foliage off of the Arum italicum. Even though it is a naturalized exotic weed, the Arum italicum was rather appealing, with its intricately lacy foliar variegation. It is completely gone now, but should regenerate once rain resumes in autumn or winter.

For now, the candy corn dog is more colorful than the Arum italicum was. How odd that it has no foliage. hmmmm . . .

Foliar Color Long Before Autumn

51104The best and brightest color in the garden is obviously still provided by flowers. Autumn color can be spectacular, but only amongst relatively few deciduous trees, shrubs and vines that turn color reliably in mild climates, and only if the weather is conducive to coloration. The next best option for color beyond green is the sort of colored foliage that does not wait for autumn to materialize.

Foliage can be shaded with varying degrees of yellow, red, pink, purple, bronze, grayish blue or gray, or variegated with white, yellow or silvery gray. Plants that display such colorful foliage can be as small as flowering annuals, or as substantial as shade trees. Many are deciduous plants that also turn color in autumn. Most of the best are actually evergreen, so hold their color through winter.

Color tends to be richest as new foliage emerges in spring, and fades more or less through summer. Gold junipers only start out gold, but then fade to green within only a few months. The purplish foliage of ‘Forest Pansy’ redbud fades to coffee stained green. Yet, bronze New Zealand flax is always bronze. Dusty miller is always gray. Some plants are more reliably colorful than others are.

Exposure is important too. Most blue or gray foliage, whether juniper, agave, spruce, eucalyptus, olive or silver Mediterranean fan palm foliage, will be significantly greener if shaded. However, white variegation of English holly, hydrangea, ivy, hosta and pittosporum have better contrast if partly shaded. Colorful Japanese maples color better with good exposure, but roast if too exposed.

Many plants with colorful foliage are notorious for developing greener mutant growth known as ‘sports’. Because sports have more chlorophyll, they grow more vigorously than more colorful growth does, and can overwhelm and replace the more desirable colorful foliage if not pruned out. Many types of white or yellow variegated euonymus, as well as the more intricately variegated New Zealand flax, can revert to monochromatic green within only a few years.

Zonal Geranium

60525New and improved is not always better. Modern garden varieties of zonal geranium, Pelargonium X hortorum, with bigger, fuller and more profuse blooms, are more colorful than the relatively weedy classic varieties, but they are considerably more demanding. In fact, because they are so unhappy through winter, they are often grown as warm season annuals instead of as perennials.

They are certainly worth growing though, and are reasonably easy to propagate from cuttings. Flowers can be red, pink, white, peachy orange or almost purple. Bloom is almost continuous. Each rounded dark green leaf might be adorned with a darker halo about halfway between the center and the outer margin. Mature plants do not get much more than three feet tall, and not much wider.

Old varieties might get twice as tall, with smaller blooms, and lighter foliage.

Leopard Plant

90410As an understory species that naturally grows under forest trees in its native environment in Japan, leopard plant, Farfugium japonicum, can be quite happy in parts of the garden that are too shady for other plants. If it does not get too warm or dry, it can tolerate full sun. It likes rich soil and frequent watering. Fertilizer should be applied moderately, since too much can cause foliar burn.

Cultivars of leopard plant that are variegated with yellow or white spots, blotches, margins or outwardly and irregularly flaring streaks are increasingly popular, although the unvariegated rich dark green cultivars are still the most popular. Individual leaves get about three to six inches wide. Some are wavy or impressively crinkly around the edges, or outfitted with a few bluntly angular teeth.

The mostly unseen rubbery petioles can suspend the glossy evergreen foliage as high as two feet, although most cultivars stay lower. Rhizomes spread slowly. It may take many years before the healthiest of specimens gets big enough to divide. Leopard plant is grown as a foliar plant, but provides a delightful surprise of loose trusses of inch wide yellow daisy flowers in autumn or winter.

Colorful Foliage Needs No Bloom

90227thumbThere is no shortage of color for the garden here in our mild climates. If we want to, we can grow various flowers to bloom at various times throughout the year. If that is not enough, we can grow plenty of colorful foliage too. Evergreen sorts can stay fresh and resilient to minor frost all winter. A few deciduous plants and warm season perennials with colorful foliage will refoliate in spring.

Besides the various shades and hues of green, foliage can be variegated with white, cream, gray, chartreuse, yellow, gold, red or pink. Such variegation can be stripes, blotches, spots, margins or lacy patterns. New spring growth of some variegated plants is blushed with pink or red. Plants with blue, gray, silvery, bronze or purplish foliage are mostly monochromatic, without variegation.

Just as most popular flowers became less efficient at their primary function of attracting pollinators, as they were bred and developed to be bigger and more colorful than they naturally were, most colorful foliage is not an an advantage to the plants that produce it. After all, foliage needs chlorophyl for photosynthesis. Variegated portions of leaves lack chlorophyl, so are much less efficient.

In fact, many variegated plants originated as mutant growths, known as ‘sports’, that appeared on unvariegated plants, and were cloned. Many try to revert back to green by producing their own unvariegated sports. These green sports grow faster with more chlorophyl, so can overwhelm variegated growth if not pruned out. Monochromatic blue or gray foliage is not mutant growth, but is instead a natural adaptation to extreme exposures, mostly at high elevations, so is not prone to reversion.

English holly, English ivy, euonymous, silverberry, New Zealand flax, mirror plant and various pittosporums are some of the more popular variegated plants. Purple leaf plum, purple smokebush and a few cultivars of Japanese maple are popular plants with purplish or bronze foliage. Blue spruce, American agave, Arizona cypress and various junipers have exquisite bluish or gray foliage.

Horridculture – Mutants


P80704Mutants are the source of many of our favorite cultivars of otherwise simpler specie. Many cultivars of plants with compact, pendulous or fastigiate (strictly vertical) growth, or variegated, bronzed, golden or otherwise abnormally colored foliage, were derived from ‘sports’, which are mutant stems that appear on otherwise normal plants. Thornless blackberries were sports of thorny cultivars. Fruitless mulberry is a sport of white mulberry. There is no shortage of mutants.

https://tonytomeo.wordpress.com/2018/05/07/cultivars-are-the-real-cloned-mutants/

https://tonytomeo.wordpress.com/2018/05/06/sport/

By nature, mutants are genetically unstable. A few can easily mutate back to their original and more genetically stable characteristics. Variegated plants are notorious for developing simple green unvariegated foliage. Because it has more chlorophyll, the unvariegated foliage grows faster, and has the potential to eventually overwhelm and replace the variegated foliage. That is why green sports should get pruned out of variegated plants.

‘President Roosevelt’ is the most popular of the few variegated rhododendrons. In nursery production, it gets pruned somewhat regularly to remove green sports. Variegated specimens are rare in landscapes because almost all revert to unvariegated foliage within only a few years.

‘Yellow Wave’ is a cultivar of New Zealand flax with pendulous yellow striped foliage. It can be seen in front of the upright greener foliage in the background. These are not two separate plants stuck together. The more vigorous green foliage is a reverting sport that should have been removed by the ‘gardener’ who is supposed to be ‘maintaining’ this landscape. The green sport is now so developed that it can not be removed without damaging the rest of the ‘Yellow Wave’ growth. It will undoubtedly be left to overwhelm and replace it. Fortunately, the upright green foliage is about as appealing as the ‘Yellow Wave’, so no one will notice the inadequacy of the maintenance. No one ever does.

Mirror Plant

70510As the old fashioned larger mirror plant, Coprosma repens, fell out of favor through the 1990s, several more colorful varieties of a more compact species of mirror plant, Coprosma X kirkii, became popular. (The ‘X’ in the name indicates that it is actually a hybrid of two specie.) Without getting much more than two feet deep, it spreads out laterally like dense evergreen groundcover.

The color is not from bloom, but from the very glossy foliage. It can be variegated with white, gold, red, pink or bronze, or completely brownish bronze. Some varieties stay very shallow. Others can be shorn into low hedges like Japanese boxwood, only shorter. Although mirror plant does not mind partial shade, foliar density and color is best with full sun exposure and occasional watering.

Most modern varieties are known by their cultivar names, without their specie names. For example, Coprosma ‘Tequila Sunrise’ lacks the species name of ‘X kirkii‘. Such omissions might be the result of confusing hybridization with Coprosma repens, for rounder leaves. In other words, some cultivars may be of ‘questionable parentage’. Some are just dwarf cultivars of coprosma repens.

Foliage Shows Its True Colors

70510thumbFlowers were originally colorful only to attract pollinators. Breeding has improved the color and quality of many garden varieties of flowers, to make them more appealing to the people who grow them. Some have been bred so extensively that they are sterile, which defeats the original function of flowers. Now their function is merely to look good in the garden. Improvements are relative.

Foliage is green because it is photosynthetic. Chlorophyll, which is necessary for photosynthesis, happens to be green. Yellow, red, blue, purple, bronze, gray and variegated foliage might not be as efficient at photosynthesis as green foliage, but can be appealing in home gardens. Many plants with colored foliage are inferior to their greener counterparts, but are somehow more popular.

Gray and blue foliage absorbs less sunlight, which can be an advantage in harsh environments. Blue hesper palm and the various blue agaves are from arid deserts. Colorado blue spruce is from high elevations of the Rocky Mountains. Arizona cypress, silver mountain gum, artemesia, lambs’ ears, lavenders, dusty millers and blue junipers all provide distinctively gray or blue foliage.

Golden arborvitaes and junipers can be strikingly gold as new foliage develops in spring, even if the color does not last long. Most plants with gold foliage fade to yellowish green through summer. Golden honeylocusts do not fade as much, so are still mostly yellow by the time they defoliate in winter. Purplish or reddish foliage of purple leaf plum and red Japanese maple holds color better.

Euonymous, English holly, osmanthus, silverberry, hosta and various pittosporums can be variegated with white or yellow. Ivy, and hydrangea can be variegated with white. New Zealand flax and mirror plant can be variegated with gold or bronze, . . . or red or pink. Any unvariegated mutant growth (known as ‘sports’) that appears on variegated plants should be pruned away. Because it has more chlorophyl, it grows more vigorously, so can overwhelm and replace the more desirable variegated foliage.70510thumb+