2015-16 Hosta Awards Announced

Chosen by American Hosta Growers*, the winners are…

2015 Hosta of the Year

Hosta 'Victory'

Hosta ‘Victory’

Victory is an impressive plant. It forms giant vase-shaped clumps with large, shiny leaves with green centers and margins that change from greenish yellow in the spring to creamy white by early summer. Victory is big hosta that grows 30 inches high by 54 inches across and produces near white to light lavender flowers in the mid-summer. Touted for its smooth textured foliage with thick substance, Victory is a great addition to shady landscapes.

 

 

 

2016 Hosta of the Year

Hosta 'Curly Fries'

Hosta ‘Curly Fries’

2016 AHG Hosta of the Year will be Hosta Curly Fries. This is a novelty hosta with extremely rippled, narrow chartreuse leaves. The mature plants are peppered with red speckled petioles. Curly Fries is a smaller hosta, forming clumps that grow to 6 inches high and 16 inches across. Just morning sunlight will bring out the best foliage color.

 

 

 

* Information and photos provided by Perennial Pulse e-newsletter.

Winter Blooming Flowering Apricot

Prunus mume on ETSU campus in Johnson City, TN

Prunus mume on ETSU campus in Johnson City, TN

Upright tree form

Upright tree form

Flowering apricot (Prunus mume) is native to southeastern Asia(USDA hardiness zones 6-8). It is primarily grown for its mid to late winter bloom of pink flowers.

This small 15-20 feet tall tree grows in average well-drained, acidic soils in full sun to partial shade. Avoid planting in heavy or wet soils. Most abundant flowering occurs in full sun. In the deep South leaves may scorch in full day sun. Prune, if needed, immediately after flowering.

A young tree tends to be branched upright. Spicily scented pink flowers bloom anytime - during a warm winter respite or in early spring. Flowers display red calyxes and yellow stamens. Flowers are followed by small 1-inch diameter, fuzzy-skinned, green to yellow apricot fruits. The ripe clingstone fruits are harvested in mid-summer and made into jams and preserves.

Occasionally, cold winter and spring temps damage flowers and subsequent fruits. Bloom buds have a staggered dormancy so that only the open flowers and swollen buds are damaged. This ensures a long period of flowering. If left unpicked, fruits may cause a mess on lawns and sidewalks. Birds help in the cleanup. Potential insect pests include aphids, scale and borers. Bacterial canker and brown rot on fruits are probable disease problems.

Flower buds are set in fall; fall-winter pruning removes some flower buds. Flowering apricot should be prune within 4-6 weeks after flowering. Annual pruning encourages new vigorous shoots that eventually bear the future flower buds. Flowering apricots are short-lived, around 15-20 years in the U.S.

Numerous cultivars are available from on-line nurseries. ‘Peggy Clarke’ struts rose-pink double flowers; ‘Rosemary Clarke’, early white petalled double-flowered form; ‘W.B. Clarke’ has double pink flowers, and graceful weeping form.

Hiring A Tree Service

 

Arborist Pruning Pine at Chicago Botanical Gardens

Arborist Pruning Pine at Chicago Botanical Gardens

The trees around your home do much more than provide seasonal beauty and cooling shade in the summer months. Just as you need to get an occasional haircut, trees (and shrubs) need pruning as well. Homeowners should invite a trained arborist to inspect their trees every 5 -7 years.

First, select a tree pruner who is licensed and bonded. Be certain that he or she shows their business credentials. Second, how many years has the company been in operation. Longevity is a good thing. Third, when will the work start and finish. Get a firm date. Don’t pay fully until the agreed upon job has been completed. A small down payment for a multi-thousand $$ job, perhaps 20% down, is okay.

Most companies are listed in telephone book (who reads that anymore) or on-line or on Angie’s List. Personal reviews from former clients who are pleased with a completed job is pretty good endorsement. Drive around and observe the aftermath of their handiwork.

Finally, consumers are in the driving seat when planning tree maintenance. Immediately following a severe storm (hurricane, tornado, ice storm) is never a good time to negotiate price. Oft-season pruning times (winter) are better times to request a cheaper rate.

Procure at least three bids and select the best one for you. Many times it is not the lowest bid that wins the job.

Sycamore Maple Performs In Cooler Regions

Last Leaves of Summer

Bark on Mature Sycamore Maple

 

 

 

 

 

 

 

Sycamore maple, aka planetree maple (Acer pseudoplatanus) is indigenous to northern and central Europe where it is a popular landscape tree. Very commonly planted in the northeastern U.S. in the early 20th century, this large 50-60 foot tree is rarely found today (USDA zones 4 and 7).  A mature specimen in Jonesborough, Tennessee (zone 6) is over 80 feet in height.

The popularity of native red (A. rubrum) and sugar (A. saccharum) maples is the likely reason that it is no longer planted. Sycamore maple exhibits subpar summer heat tolerance which excludes its use in the southeastern U.S. The 4 – 6 inch broadly palmate leaves feel sand-papery to the touch. Leaf petioles are 4-5 inches long. Mature specimen trees display grayish brown bark which chips off in tiny narrow strips to expose orange-red inner wood. Its green clusters flowers in spring contribute little to the tree’s overall stature; leaves turn a bland yellowish brown before abscising.

There are two diminutive cultivars which are more deserving your planting attention. ‘Brilliantissima’ exhibits salmon pink spring foliage which turns bright lime-green in summer. ‘Esk Sunset’ foliage starts off with pink, green and white variegation, and turns lemony green in the summer. Both cultivars grow very slowly,  perhaps to less than a third the size of species (20-40 feet in height and 12-15 feet in spread).

Sycamore maple grows in average well-drained soil and is not pH sensitive, even high lime soils. Leaves are exceptionally tolerant of salt and urban air pollutants. Annual growth rate is fast and the upright branches of this hardwood maple are very sturdy. Sycamore maple distribute thousands of fertile double winged samaras (“whirligigs”)annually and seeds invade surrounding landscapes. Pennsylvania lists sycamore maple as invasive.

Sycamore maple is available from  a number of on-line nurseries.

Take A Second Look At Canadian Hemlock

Large hemlock hedge at Biltmore Estate, Asheville, NC

Large hemlock hedge at Biltmore Estate, Asheville, NC

Hemlock at Yewdell in Louisville, KY

Hemlock at Yewdell in Louisville, KY

 

 

 

 

 

 

 

Canadian hemlock (Tsuga canadensis) is a native evergreen species which is available in many forms: prostrate, globose, weeping, fastigiate and variegated (USDA Hardiness Zones 3-7). Its tremendous versatility as a hedging tree or shrub  in planting sites is also a great reason to continue to include hemlock in the landscape. Hemlock may be planted in full sun to moderate shade and does quite well.

Negative publicity continues hurt the sales of this evergreen. For nearly a half century, hemlock wooly adelgid, a serious insect pest from eastern Asia,  has devastated hemlocks in the eastern U.S. forest lands. Adelgid infestations continue to move across the country.

Plant scientists have developed workable strategies for nursery producers and homeowners to combat wooly adelgids. In addition, the severe winter weather of 2013-14 reduced adelgid populations in large landscapes and forest lands. Parasitic beetle releases in state forests are helping to reduce adelgid numbers. Pesticides continue to be very effective in managing this pest without environmentally damaging the treated areas.

The American Conifer lists over 250 cultivars of just Canadian hemlock. Many are slow-growing and somewhat pendulous.

Short List of Cultivars to Plant…

‘Cole’s Prostrate’ or ‘Cole’ -  slow-growing, ground hugger ideal for rock gardens; or graft on a short standard; 3 feet after 10 years.

‘Everitt Golden’ –  new spring growth with golden tints; compact 5 feet high by 4 feet wide shrub after 10 years.

‘Frosty’ – white tipped new spring growth that fades; 3-6 feet globe form after 10 years.

‘Gentsch White’ -  slow-growing, globe form with variegated branch tips; 5-6 feet after 10 years.

‘Jeddeloh’- mounding or nest-like habit; 3-6 feet height after 10 years.

‘Lewis’ – dwarf with upright branched; 3-6 feet height after 10 years.

‘Sargentii’ – aka ‘Pendula’, broad spreading weeping form that can reach more than 10 feet high and 20 feet wide.

‘Watnong Star’ – new shoots almost white; needle arrangement appears star-like on strong 2-inch to 2½-inch shoots.

Worldwide, there are five other major species of hemlock other than Canadian hemlock. They are Carolina hemlock (T. caroliniana), western hemlock (T. heterophylla), mountain hemlock(T. mertensiana), and Southern Japanese hemlock (T. sieboldii), and Northern Japanese hemlock (T. diversifolia).

Mt. Cuba Center Evaluates Heuchera (Coralbells) Cultivars

Heuchera 'Mocha'

Heuchera ‘Mocha’

Heuchera 'Apple Spice'

Heuchera ‘Apple Spice’

 

 

 

 

 

 

 

Over the past quarter century, gardeners have enjoyed the wonderful heuchera revolution (USDA hardiness zones 4-9). A great many hybrid cultivars have been introduced with more arriving every spring. Unfortunately, the flood of new cultivars has given us a huge number of poor selections. As I talk with gardeners across the U.S., it has become obvious that there are regional diffences among heucheras. A poor performing cultivar in the Southeastern U.S. may shine in the Mid-Atlantic or Midwestern U.S.

Heucheras are herbaceous perennials with palmate leaves attached by long petioles to a thick basal stem. Foliage emerges in spring with a second growth flush coming on in late summer if plants are not environmentally stressed. Leaves are reliably evergreen in plant zones 7-9.

There is an enormous number of hybrid cultivars including leaves with ruffled margins, colorful venation , et al. Plant breeders have made significant improvements in toughness, performance, and foliage. H. americana and H. villosa have lent hardiness, vigor, and color. Heucheras thrive planted in moderate shade or full morning sunlight (in zones 5-7).

From 2012-14 Mount Cuba Center near Greenville, Delaware evaluated 83 varieties. The best performers were: Citronelle, H. villosa Bronze Wave, Cajun Fire, Color Dream, Steel City, Carousel, Apple Crisp, Frosted Violet, Southern Comfort, Spellbound.

Highly rated were: H. villosa ‘Autumn Bride’, Brownies, Creole Nights, Dark Secret, Guardian Angel, Miracle, Pinot Noir, Plum Pudding, Rachel.

How to use this data? Read the entire report on the Mt. Cuba website posted under” research”. If you garden in the Mid-Atlantic states or in zones 5-6, this regional report should be of value. For mid-westerners, a 4 year heuchera trial conducted by Richard Hawke was published by the Chicago Botanical Gardens (CBG) in 2003 and is still available for viewing on the CBG website. Dr. Leonard Perry at The University of Vermont has also evaluated heucheras in previous years.

What Roses Need

Double Pink Knockout at UT Gardens, Knoxville, TN

Double Pink Knockout at UT Gardens, Knoxville, TN

Rosa 'Shock Wave'

Rosa ‘Shockwave’

 

 

 

 

 

 

 

A goal of most rose gardeners (rosarians) is to grow them almost maintenance free. The improved shrub roses introduced almost two decades ago have brought this too reality. Rose series such as Knockout®, Home Run®, Drift®, OSO Easy®, Carefree® and Meidiland™ are among the best.

No matter the pedigree of the rose, selecting a poor site, doing something wrong, and new disease problems can disappoint your love affair with roses. Providing a good environment makes growing roses a lot more enjoyable:

  • Plant in soil with good moisture drainage
  • At least 6 hours of sunlight
  • Adequate spacing between shrubs to allow good air circulation
  • Shelter from high or drying winds
  • Little competition from other plants
  • Irrigate ground but keep foliage dry (drip, soaker hoses); best time to water is early morning
  • Fertilizers: either a water soluble fertilizer (3-4 times in growing season thru early September); or 10-10-10 (in early spring and mid-July); or slow release fertilizer once in early spring.
  • Organic fertilizers (as alternative):
  1. N (nitrogen) -horse manure – yes!; cow manure –no! (full of weed seeds)
  2. P (phosphorus)  – roses crave P, very important; sources: bone meal, rock phosphate
  3. K (potassium) - improve summer heat tolerance
  4. Minors- Fe (chelated iron) and Mg (Epsom salts)
  • Mulch with 2-3 inch layer of pine needles, bark chips or nuggets around bushes, but not against trunks.
  • Keep roses weed-free as weeds compete and also attract harmful bugs and diseases
  • Prune roses in late winter or spring when dormant or starting to bud out
  • Prune in summer to remove disease wood, particularly rose rosette or other virus problems

 

 

Blue Atlas Cedar Becoming Very Popular In Urban Landscape

Blue Atlas Cedar at  Dallas Arboretum

Blue Atlas Cedar at Dallas Arboretum

Blue Atlas cedar (Cedrus atlantica ) hails from the Atlas Mountains in northern Morocco and Algeria (USDA hardiness zone 6). The cultivar ‘Glauca’ has been the popular choice because of its blue green foliage. Blue Atlas grows to 40-60 feet in height, but individuals over 70 feet are hard to find. Mature forms, those 50 years or more age to become conifer aristocrats.

Atlas cedar is a “true” cedar. In its early years, Atlas cedars grow tall and narrow with rigid upright branches. Young tree framework is strongly pyramidal. As it ages, overall tree canopy widens, taking on a slightly weeping form. Tufts of 1-inch long deep blue needles develop from late spring through early fall. Needle color over winter washes out to slate blue; needle color plus medium gray bark are handsome winter features.

This conifer prefers a deep, well-drained, slightly acidic soil. Never plant on a tight poorly drained soil where water may stand over several days. Allow plenty of room for branches to spread gracefully. Its ability to handle snow loads is debatable. Pest and disease problems are rare if planted on an open site in full sun and with good air movement. Permit 2-years for establishment with backup irrigation over long dry spell. A multi-year old tree exhibits exceptional heat and drought toughness.

The 3-4 inch long cylinder shape cones lay above the needle foliage and need two years to mature. Purchase grafted nursery stock as seed produced plants do not hold their needle color year-round.

Their enormous size makes them ideal selections planted in spacious public areas such as urban parks, golf courses, industrial parks, wide boulevards, and cemeteries. For narrow restricted spaces, select the upright cultivar ‘Fastigiata’. ’Glauca Pendula’ is an awesome weeping form, but requires staking in its early years to attain its desired height and form.

Personal note: I have seen 100+ year old specimens in the northeastern U.S. which stand tall and majestic for a century and more.

Many Shapes and Sizes Of Cryptomerias

Crypt 'Radicans'

Cryptomeria ‘Radicans’

 

Cryptomeria 'Globosa Nana'

Cryptomeria ‘Globosa Nana’

Japanese cedar, aka cryptomeria, (Cryptomeria japonica) is the national tree of Japan and is also indigenous to China (USDA hardiness zones 5 to 8).  Cryptomeria cultivars vary greatly from very dwarf to rounded shrubs to large tree forms. Needle-like foliage may be dark green, medium green, golden or contorted leaves.

Cryptomerias tolerate hot humid summers and prefer deep, moist, well-drained soils with an acidic to neutral pH, and in full to half-day sun. Two-year trees are moderately drought tolerant.

Spring-summer foliage is bright green; leaves of many cultivars often turn bronzy in winter. Gold needle cultivars are available but not listed here. The rusty red bark, peeling in vertical strips, is also very attractive; older trees are frequently limbed up to show off the bark.
Cryptomeria contracts no major pests and diseases. On occasion, a fungal blight causes inner needles to turn reddish brown; prune out discolored foliage and toss from the property.

This mighty evergreen is wind tolerant, standing up to strong hurricanes; needles are salt tolerant. The upright branches hold up well to snow loads. Tall cryptomerias are easily trained and maintained as a tall single leader tree and utilized as privacy screens or windbreaks.

Cultivars to plant:

Tall tree forms…

‘Yoshino’- the most popular cultivar at 30-40 feet height; bright green needles bronze off in winter in zone 6.

‘Ben Franklin’- difficult to find at nurseries; similar to Yoshino in size and form; needles retain their green color through most of winter.

‘Radicans’ – tall upright pyramidal form, 20 to 30 feet tall x 7 to 10 feet wide; eventually to 40 feet high at maturity; holds its very dark green color throughout winter compared to Yoshino.

Intermediate…

‘Black Dragon’ –medium height @ 10-12 feet high x 6 feet wide; deep green needle-like leaves.

‘Gyokuryu’ – compact upright pyramid habit @ 10-15 feet high; dark green foliage with slight winter bronzing.

Shrub forms…

‘Globosa Nana’ – compact shrub form 2 to 3 feet high and wide, almost ball shaped.

‘Elegans Nana’ – globose compact form to 5-6 feet high.

‘Tansu’ – 2 feet x 3 feet dense compact form with rich green foliage; slow grower.

Twelve Days Of Christmas Showcase At Dallas Arboretum

Seven Swans A-Swimming

Seven Swans A-Swimming

Ten Lords A-Leaping

Ten Lords A-Leaping

 

 

 

 

 

 

 

 

The Dallas Arboretum in Texas is hosting a festive holiday exposition: The Twelve Days at Christmas. It is an elaborate collection of 25-foot Victorian gazebos themed to “The Twelve Days at Christmas”. Each of 12 gazebos is comprised of  charming costumed characters and whimsical animals made famous by the beloved Christmas carol.

Each gazebo is richly decorated and encased in glass, permitting a 360º three-dimensional view. Each of the 12 showcases are mechanically animated and accompanied by holiday musical classics that bring the characters almost to life. Around each gazebo Arboretum staff have decorated with many kinds of large evergreen trees for a wintry feel.

The Arboretum has extended daily visitation hours into the evening hours (until 9 p.m.) during the exhibit’s run which ends on January 4th. Each gazebo is illuminated for magical nighttime viewing. In addition, visitors will become further immersed in the Victorian-era holiday theme by live carolers and holiday treats served in the arboretum’s cafe.

If you missed it 2014, the Arboretum plans to make The Twelve Days at Christmas exhibit an annual holidays showcase.