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Current weather

Thursday, 04/24/2014

  • Waterloo
  • 46° F

©: AccuWeather

Shamrocks or Oxalis?

In this month of March, when Irish heritage is celebrated, we frequently see plants for sale called "shamrocks", but are they?

What is a shamrock? The term comes from the Gaelic word "seamrog" which means "little clover."

The early Celtic peoples considered shamrocks as a charm against evil spirits, and this pagan tradition was adapted by Christian missionaries to represent the symbol of the Trinity. It is now an emblem of Ireland.

There are many species of clover, even just in Ireland. In 1893, botanist Nathaniel Colgan published a study in the Irish Naturalist. He wrote: "I was take into hands once more the inquiry into the species of our national badge..." He sent requests to many of the Gaelic speaking counties for specimens of the original shamrock "certified as genuine by competent authorities." He also received roots from Trinity College Botanic Garden, and in Dublin from "three different itinerant vendors, each of whom was required to exercise the most scrupulous care in the selection of the genuine plant from the obviously miscellaneous collection in her basket." Botanist Colgan planted the 35 specimens he received, which grew into 4 different varieties of clover, but the "decided preponderance" grew into Trifolium repens, otherwise known as white or Dutch clove, which is the clover variety that Iowans most commonly see in their yards. Today, it still appears in Ireland that more than one type of clover may be sold as "shamrocks".

So what are we seeing in local stores this month? These are usually species of Oxalis, which is the largest genus in the wood-sorrel family. There are over 800 species of Oxalis, and they are most abundant in the Southern Hemisphere. The leaves of most Oxalis have three leaflets, and are shamrock like in appearance. Some leaves and flowers are light sensitive and tend to close up at night.

Oxalis regnelli, which is a South African native, is frequently sold in March labeled as a "shamrock". It has the bright green leaves, which close in evening, and bright white flowers.

Oxalis triangularis is another common species, with purple leaves which have a rose pattern, and pink flowers.


Both of these Oxalis have fleshy, rhizomatous bulbs, and can be easily transplanted outside to enjoy all summer. They prefer semi-shade and rich soil, and would need to be potted prior to fall frost to assure survival. They are easy to grow indoors in good light, and can cheerfully bloom all winter. You don't need to luck of the Irish to be successful with Oxalis!

The Beauty of Mexico

by La Rae Randall

At the beginning of February, my husband and I traveled to the beautiful country of Mexico for our honeymoon. During this trip, we stayed in Cancun and traveled to the ancient Mayan city Chichen Itza as well as the last Mayan city Tulum. During our wonderful week-there, we experienced not only spectacular weather (84° and sunny the entire time!), but also the beautiful flowers and plants of the Yucatan Peninsula.

The Yucatan Peninsula was once completely jungle. With such a lush environment for growing, it’s easy to understand why it fosters such interesting plants! Of course, all flora is adapted to the host climate; to survive in the jungles of Mexico, plants must love heat, humidity, and being near water.

One prominent native plant that is seen throughout Mexico is Agave. Agave, a succulent, has thick, waxy leaves that hold water in them. Every part of the Agave plant is edible and was once a major food source for the Mayan people. And, as many know, this plant (specifically, Blue Agave) is used to make tequila, which can only be legally made in Mexico.

Cordyline (above) is a palm-like plant that is native to tropical climates. It has a striking appearance as its magenta color is unusual for a plant. We saw the cordyline everywhere we went!

This flower is called Bougainvillea. It is an extremely hardy and versatile plant that can be seen in many different colors. I mostly saw this flower in pink and red, as show (sorry about the blurry photo!).

Here are a few other photos just in case you’d like to pretend it’s 84°.

"Agave." Better Homes & Gardens. N.p., n.d. Web. 24 Feb. 2014.

"The International Cordyline Society." The International Cordyline Society. N.p., n.d. Web. 24 Feb. 2014.

"All About Colocasia Plants." Colocasia Plants. N.p., n.d. Web. 24 Feb. 2014.

"Bougainvillea 101." Bougainvillea Growers International. N.p., n.d. Web. 24 Feb. 2014.

Gardens and Greenery in Alaska-January 2014 View

by Rita Lynn

During my tour of our incredible state of Alaska last summer, I kept at least one eye open at all times to gardens and vegetation. I wanted to know what grows there, and how Alaskans use their “green thumbs." I didn't get to the coldest parts of the state, but I got as far north as Fairbanks and as far south as Sitka. My travels took me to the tundra areas of Denali National Park and to the temperate rain forests of the southeast coast. No matter where I was, the flora offered beauty and bounty.

As is the case everywhere else, weather is a big factor. In Fairbanks, the growing season in the past 20 years or so has lengthened to about 105 days, although killing frosts as late as June 5 and as early as August 19 have occurred in that same time span. Wilderness areas show the characteristics of the boreal forest. Only six species of trees - spruce, poplar, larch, birch, aspen and tamarack - survive there. In the understory you find such plants as equisetum, commonly known as woodland horsetail, and bunchberry, a dwarf dogwood. For the home gardener, starting seeds indoors in flats or buying seedlings is necessary to grow most flowers and vegetables. On the other hand, garden plants can bask under the midnight sun. Once in the ground, plants have the benefit of daylight up to 24 hours a day, allowing them to grow quickly while they have the chance, and encouraging the development of brilliant blossom color. I spent several hours at the University of Alaska Fairbanks Georgeson Botanical Garden. It was July, but peonies, among a healthy array of other flowers, were in full bloom and absolutely stunning. Other exhibits spotlighted vegetables which, with the long days, grow to phenomenal size. Informative signage noted that a cabbage grown in an area near Anchorage, for example, weighed in at 127 pounds. (That's a lot of sauerkraut!) Researchers associated with the garden are experimenting with the use of black mulch to warm the soil, allowing earlier planting and growth, thereby extending the growing season. Could such a technique be of use here in Iowa in years when spring takes its good old time, like it did last year?

Vegetation in the southeast coastal areas is affected by conditions quite different from those further north and inland. This is a temperate rainforest, so the problem isn't temperature as much as it is available sunlight. Temperatures are actually more moderate than ours in Iowa - cooler in the summer, and not as cold in the winter. With all the moisture, wilderness vegetation is lush. Forests are dominated by the Sitka spruce, Western hemlock and red alder. The understory sports such plants as ferns, blueberry and salmonberry shrubs, and the dangerously thorny devil's club. Within the cities of Juneau and Sitka I was particularly impressed with the displays of flowers. Perhaps the colors seemed more brilliant because the weather was so drab when I was there, but it was as if residents, after their long and dark winter, defy the often dreary weather by putting color in every available space. City parks were showcases of flowers, and flowers lined the sidewalks and filled people's yards. People who have vegetable gardens have best success with cooler season varieties such as lettuce, plants in the cole family, and root vegetables. Warm season crops such as tomatoes require protection and usually do not produce well, because they just can't get enough warmth and sunshine. Southeast Alaskans also harvest from the sea, incorporating seaweed and coastal plants such as beach asparagus, along with lots of fish and other plentiful seafood, into their diets.

If we moved to Alaska, our houseplants would need artificial light in the winter (as would we), and we'd have to make significant adjustments to our gardening practices. But, like the folks who live there now, if we wanted a garden, we could certainly have a bountiful one. And if we were in search of awesome natural beauty, we would find that in abundance, even though it comes in forms much different from that in Iowa.

All about Poison Ivy-December 2013 View


By Rita Lynn

             Early this fall, when trees were just barely starting to show color, I was walking in the woods and spotted brilliantly colored leaves on vines growing up trunks of trees. These splashes of red, orange and gold stood out in the woods and pierced an otherwise gray day with beauty. As I suspected, closer inspection revealed that the show was being put on by poison ivy.

            Everyone who spends any time outdoors should be able to identify this plant because of its ability to cause uncomfortable and sometimes dangerous rashes to susceptible people. Perhaps you have heard the saying, “Leaves of three, let it be!” The plant does indeed have clusters of three leaflets, with one leaflet at the end of the leaf stalk (petiole), and the other two leaflets arising opposite each other lower on the petiole. These lower leaflets are often shaped like mittens, but in truth, the color and shape of the leaves is highly variable. Poison ivy (Toxicodendron radicans) grows in many forms, from bushy plants to vines that climb entire trees, and it is found all across the United States. Oil, technically called “urushiol,” produced by all parts of the plant and most potent in the sap, is what causes reactions in human skin.   

            Not everyone is sensitive to this oil. Some people haven’t been bothered by it and some get just a slight, short-lived itchy rash. Beware, however, if you haven’t ever reacted to poison ivy. Sensitivity can develop at any time, so it’s best just to avoid exposure no matter what. You can get a rash from touching any part of the plant, by being sprayed by the oil as the leaves are cut, or even by touching an object or an animal that has come in contact with the plant. Your skin absorbs the oil quickly, some say within half an hour. Therefore, washing with detergent - or even plain running water if that’s all that’s available - as soon as possible is important.   Once the oil is on an object, however, it is very stable and can remain potent for as long as a year. Consequently, contaminated objects need to be carefully discarded or thoroughly cleaned.

            Treatment for mild cases of poison ivy rash involves using topical medication available over-the-counter. Interesting home remedies to relieve itching from such irritations include using heat in the form of hot water or a hair dryer, applying the sap from jewelweed, or spraying with deodorant containing aluminum. In the most susceptible people, the initial rash can develop into inflamed, swollen lesions with open weeping sores that can last for two or three weeks and may require medical intervention. Even worse, people have been known to suffer from exposure to their lungs from breathing smoke when poison ivy is burned, sometimes resulting in a need for hospitalization.     

            If you discover poison ivy growing in your yard, eradicating it requires caution and may take some time. By no means should you burn the plants or try to pull them up your bare hands. The best time to start the elimination effort is May through July when the plants are flowering. Spraying with glyphosate (sold as Roundup and other herbicides) is the safest method, although other plants in the area might be damaged. Vines should be cut off about 6 inches above the ground and the stump treated with the glyphosate according to package directions. The plant spreads by its tough roots as well as by having its seeds dispersed by birds. Eradication may take several applications of herbicide and efforts over several seasons.     

            Scourge that it is to humans, animals and birds are not affected by urushiol. There is much to be said in defense of poison ivy on their behalf.  Small animals, birds and insects use poison ivy for shelter, and birds then feed on the insects hidden in the vines. Mammals such as deer browse on the foliage. Perhaps most importantly, poison ivy produces grape-like clusters of white berries. Robins, grosbeaks, chickadees, finches and juncos are some of the birds that are attracted to the berries, available in fall and winter when other food is scarce. And dare we mention its function as a hardy ground cover, or that it is truly beautiful in the fall? So when you see poison ivy in the wild or even in a remote area on your property, stay away from it, but try to remember that it is a treasure to the environment and to the rest of the animal kingdom.


“Poison Ivy,”

“Poison Ivy,”

“Poison Ivy,”

“Poison Ivy Control,”

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