Plant Preview

Welcome to Plant Preview, a blog dedicated to helping gardeners learn about gardening techniques and preview new plant cultivars. Read about new plants here first and hear how your "comrades in compost" are making use of new plant introductions in their gardens and landscapes. Blog author Geri Laufer is a life-long dirt gardener, degreed horticulturist, author and former County Extension Agent. Plant Preview is copyrighted by Geri Laufer.

Thursday, November 25, 2010

Thanksgiving Nature Walk

This year our traditional American Thanksgiving dinner is scheduled for 6 pm Friday, so on this beautiful, sunny 72-degree Thanksgiving Day we were able to enjoy a walk in the nature preserve connecting our neighborhood with the next one over. The leaves are still brilliant with fall color. 

We spotted wild ginger, and an old summertime squirrel's nest. 

The American Beech leaves are mostly their lovely brown hue but some are still changing.

We walked along South Peachtree Creek and noticed how the sky is reflected in the water. Today the sky is a dark blue. 

We found an old rock cairn; it wasn't a chimney. 

These photos were just taken by gardengeri and David Laufer. 

Monday, November 22, 2010

Tree, Bush & Shrub

The word ‘tree’ brings to mind a tall, woody, permanent (perennial) plant with a main trunk and heavy branches forming a distinct elevated crown of twigs and leaves. Both gymnosperms (cone-bearing) and angiosperms (flowering plants) can grow in a tree form. Fire Dragon® Shantung Maple is a typical example with a single trunk and a rounded crown.  

Teddy Bear® Magnolia is a tree that offers evergreen color and fragrant flowers in spring.

Contrast this with a bush or a shrub.  Scratch that; the term 
‘bush’ is strictly non-scientific and colloquial, and although in conversation people use the words interchangeably, it is shrubs we wish to discuss. The gestalt or overall concept of a ‘shrub’ is a low, woody, perennial plant with several woody stems, and is very different from a tree. 

An extreme example of a small shrub form is Micron® Holly with a characteristic mounding or pillowing habit, making this compact, multi-branching shrub distinctive in the landscape. 

Perhaps a more typical example of an upright, multi-branched shrub is Green Borders Boxwood

But as gardeners know, Nature does not like black and white, but prefers Countless  shades of gray. And so there are multi-trunk trees like Birch and Willow, and also low-growing trees that branch near ground level such as dissected-leaf Japanese maples. As well, there are shrubs that tend to have only one trunk like some Crape Myrtles and very tall shrubs like lily-flowered Magnolias (or maybe these are multi-trunk trees?). There’s a mind-blowing discussion at the Native Tree Society 

Trees are permanent fixtures that define the landscape and offer shade, windbreak, ornament and even fruit. Shrubs anchor the landscape with their multitude of sizes, forms, leaf- and twig-colors and flowering habits. Evergreens in either category provide stability and winter color. Both are easy to care for and will increase in beauty over time with minimal effort. 

What shrubs and trees are growing in your landscape? 

Diagram Credit Susan Grace 
Photo Credit, Landscape photo Don Vandervort

Friday, November 19, 2010

What’s in a name? Naturalized Plants or Invasive Exotics

Somewhat like fashion, horticultural perspectives change over the years, going in and out of vogue.  In my Wyman’s Gardening Encyclopedia, first published in 1971 as a “bible for American and Canadian gardeners by the dean of American horticulture” and its second edition of 1986, I had occasion to look up ‘naturalized.’  A brief paragraph informs that it is ‘a horticultural term for an exotic plant that has escaped from formal garden planting and become established and is increasing “on its own” in the new country. Many European plants, especially “weeds” have become “naturalized” since first being brought to America by the early settlers.’

When I looked up “exotic” all it had to say is ‘Foreign, not native.’  And “invasive” was not even listed.  

As an example, in Wyman’s Gardening Encyclopedia Honeysuckle is extolled as ‘easily grown’ and it notes that ‘their chief ornamental value is their [fragrant] flowers, their colorful fruits and their ability to grow under various conditions. Fruits of the honeysuckles range in color from bright red and yellow to dark blue and black, and some are whitish and translucent. They are most attractive to the birds.’ Its vigorous growth is not even mentioned.  

Yet today’s more sophisticated media emphasizes the harmful effects on native flora and ecosystems resulting from planting the Japanese honeysuckle vine. Search by name on the internet and more attention is paid to the invasive nature of this exotic species than to its ornamental qualities. 

For example, in the Wikipedia article there are more lines about the invasive qualities of Lonicera japonica than there are about its description and uses combined. The U.S.D.A. site  calls it a noxious weed, the Floridata page has a warning symbol and text, while the Center for Invasive Species and Ecosystem Health lists dozens of  states and organizations naming it a ‘severe threat.’  

When I checked the Martha Stewart website under Gardening, the entry was all about features.  Features included ‘attractive flowers, attractive foliage, attracts butterflies, attracts hummingbirds, and fragrant. Garden uses included ‘climbing, containers and ground covers.’ Guess something got overlooked this time. 

To learn more, join your local Native Plant Society. They focus on beautiful ornamental natives and on combating invasive exotics. Are you a member? 

photo credit: Emilycompost website for Japanese Honeysuckle picture

Thursday, November 11, 2010

Brilliant Tree Leaf Color

In autumn, people are revved up by the fall color phenomenon and “leaf peepers” make trips to view fall foliage and changing forest colors. Strongbad1982's Autumn Leaf map (right) is released to the public domain. Albert Camus noted Autumn is a second spring where every leaf is a flower. "  

Autumn color occurs at the end of summer as the days get shorter because green chlorophyll levels in the leaves begin to decrease, revealing the yellow and orange pigments that have been hidden since spring. Carotenoid pigments are present in the leaves year-round, but are masked by chlorophyll, so leaves look green in summer. In fall as the supply of chlorophyll dwindles, the other pigments are able to show through. Carotenoids are the dominant pigment in the autumn coloration of 25% of the hardwood tree species producing brilliant yellows and oranges (for example, ash, aspen, birch, hickory, maple and sassafras).

Sometimes carotenoids are present in such abundance that the plant has an orange or yellow color all year long. Take carrots for instance. Or take the leaves of  The Rising Sun™ Redbud from Garden Debut®. New growth (left) remains apricot-tangerine all year (at right), while mature leaves are bright yellow until late spring, turning green in summer, then changing to golden yellow for fall.

The bright reds and purple combinations that enliven tree species in autumn in temperate regions result from another pigment, called anthocyanin.  Anthocyanins develop in late summer as the glucose in leaf sap breaks down in the presence of bright sunlight and decreasing levels of phosphate. The most brilliant colors occur during a period of cool-but-not-freezing nights and days filled with bright, plentiful sunlight, which increases production of anthocyanins and results in the most eye-catching color displays.  In New England, forests appear vivid with reds, purples and brilliant maroons because up to 75% of tree species produce these colorful anthocyanins (such as Cherry, Dogwood, Maple, Oak, Parrotia, Persimmon, Sourwood/Tupelo and Sweetgum).  

In spring, anthocyanins temporarily color the edges of some young leaves as they unfurl from buds. One example is Garden Debut®'s Fire Dragon™ Shatung Maple PP 17367. Acer truncatum is also known as ‘Purple Blow’ Maple, due to this light reddish-purple spring color on new growth. After a green summer, fall color is strong, pure, bright red reported from Oregon to New York and Virginia to Arkansas, Oklahoma, Texas and all the way to Houston. 

Another example of a pigment overcoming chlorophyll in summer is the dark wine red leaf color of Burgundy Hearts® Redbud PP19654.  An abundance of anthocyanins suppress the chlorophyll, yielding the dark red heart-shaped leaves.  

The combination of all of these pigments produce the beautiful fall foliage colors ranging from the palest buttercream yellow to deep orange, fiery reds, purples and bronzes, while brown colors like leathery Oaks) are made from the cell walls and metabolic wastes left in the leaves.

What's your favorite? Will you post favorite fall leaf photos? 

Monday, November 8, 2010

Container Herb Gardens from Greenleaf Nursery Company, NC

Rummaging around on the Facebook Page of Greenleaf NC I found some lovely Container Herb Gardens that they have made up. Find them in your favorite retail garden center. The one at left contains Flat Parsley, Chives and is called their "Mashed Potato Blend". 

Although I think outdoors-in-the-ground is best when growing herbs, not everyone has the luxury of a garden area. The majority of herbs need full sun and high light intensity, excellent drainage and a sweet soil on the alkaline side. Several herbs will fit quite nicely into the smallest scrap of ground. But if you wish to grow some fragrant and culinary herbs thrive in planter boxes or containers, keep in mind a few simple rules.

Herbs need excellent drainage in containers or in the ground, so for planters choose a potting mix labeled for cactus, or add sharp river sand or extra Perlite to the potting soil to allow water to drain quickly. Make sure plants are watered regularly – sparingly at first, then more thoroughly as the plants become established and fill the pots. It’s standard practice to water well so that the water comes through the drainage hole at the bottom, but afterward never let them sit in water; simply empty the saucers after a few minutes. The old fashioned tip of first adding an inch or two of pot shards or pebbles at the bottom of the pot is no longer approved, as research has shown it merely shortens the water column inside the container and keeps the soil soggier. Finally, individual pots can dry out quickly; larger containers that hold several favorite herbs at once is the way to go.

Because many of the fragrant and culinary herbs evolved in the Mediterranean or Near East, they prefer an alkaline soil, achieved by adding some pulverized lime to the potting mix before potting up. This is especially true if the soil-less potting mix has a peat moss base, which is naturally very acidic.

Finally, here’s hoping you have a south-facing deck or balcony. Full sun is best, and herbs become pale green, weak and spindly when someone attempts to grow them indoors. Even grown under fixtures having four, high wattage, fluorescent Grow-Lights, herbs grown indoors can’t compare with outdoor-grown ones.
Keep container grown herbs in a sheltered, sunny place, and if a hard freeze is expected, lug them indoors overnight. When harvesting, snip a leaf or two all the way to the base, rather than shearing the tops of several leaves. Add to Thanksgiving stuffing or salad for a taste of summertime. 

The container on the right (above) is called the "Turkey Herb Blend" containing Tri-colored Sage, Tuscan Blue Upright Rosemary and Creeping Thyme, recommended for a healthful main course, while the third photo bottom left is the "Stuffing Herb Blend" planted with Italian Parsely, Creeping Thyme and Sage, best used to season the stuffing for a memorable Thanksgiving menu. Next spring, remove the herbs from the container and plant in the garden for continued enjoyment. 

Photos courtesy of the Greenleaf Nursery Facebook Page.