What Grows There :: Hugh Conlon, Horticulturalist, Garden Advisor, and Photographer

Fall Is Spring Bulb Planting Time

Posted by Hugh on October 18th, 2013

Mix of Tulips and Pansies at Callaway Gardens

If you love spring flowering tulips, daffodils and other spring-flowering bulbs, some planning and planting chores should be set into motion this fall. Spring flower bulbs should be planted when cool soil temperatures (below 55 °F) return. For gardeners living in the Southern Appalachian region (USDA hardiness zones 6 and 7), bulb planting begins in early October and ends when the ground freezes or around the first of the New Year.

Bulbs and corms (ex. crocus) should spend the winter in the cold moist ground. They may also be potted in moist soil-less media and stored in a refrigerator for 90 days or more. This mimics the outdoor garden environment. Refrigerated bulb pots can be forced to bloom indoors in February and March. Cover the pots with shrink wrap or in plastic bags to prevent the potting media from drying out or foul smelling your refrigerator.

If you have lots of bulbs to plant in the garden, invest in a power drill and an augur. Most garden centers sell augur bits. This tool makes bulb planting alot easier physically. A recommended depth chart should be available where you purchased the bulbs. Mark the proper depth on the augur with tape. After 5-6 holes, you’ll become a planting pro.

If the bulbs are planted before October 15th, consider inter-planting with winter hardy pansies and violas. Pansies will guarantee a blast of color from fall into late spring while you’re waiting for bulbs to poke through in late winter.

If you can’t plant bulbs right away, store them in a cool, dry place with good air circulation. If you purchased bulbs earlier and found them partially sprouted in the garage, plant them immediately, even if you need to use a pick axe in an icy soil. Most should come up and bloom feebly the first year.

Popular Landscape Trees Deer Don’t Like

Posted by Hugh on October 15th, 2013

Red Buckeye

Flowering Dogwood

This title is somewhat misleading. Deer will eat or sample (nibble) on any landscape plant, particularly if they are hungry enough. Deer also do not read lists of plants they’re suppose to leave alone.

The following list of deer resistant plants is a sampling from reports across the U.S. It does not include every tree reported. Deer species and numbers vary across this big country. A deer’s food palate may also differ from one region to another. It also depends on how hungry the numbers of deer in an area may be.

Some native trees such as American beech, buckeyes, green ash, persimmon, hophornbeam, and flowering dogwood are important food resources for deer and other wildlife. But, they do little significant damage to their host tree(s). If you are trying to introduce young host trees into a landscape, you should fence them off for 3-5 years until they become larger and better established. Finally, prune up low branches out of reach of deer feeding.

Abnormally high deer populations starved for a lack of their favorite foods (mast) will eat or browse on almost any plant. This is a survival reaction. To truly protect plants from deer when deer numbers are unusually high, a tall fence or reinforced netting may be your best options.

Deer Resistant Tree List:

Paperbark Maple (Acer griseum)
Japanese Maple (Acer palmatum)
Striped maple (Acer pensylvanicum)
Norway Maple (Acer platanoides)
Red Maple (Acer rubrum)
Sugar Maple (Acer saccharum)
Ohio Buckeye (Aesculus octandra)
Red Buckeye (Aesculus pavia)
Mimosa (Albizia julibrissin)
Downy Serviceberry (Amelanchier arborea)
Shadblow (Amelanchier canadensis)
Allegheny Serviceberry (Amelanchier laevis)
Pawpaw (Asimina triloba)
Himalayan Birch (Betula jacquemontii)
Yellow Birch (Betula lutea)
River Birch (Betula nigra)
Paper Birch (Betula papyrifera)
European White Birch (Betula pendula)
European Hornbeam (Carpinus betulus)
Deodar Cedar (Cedrus deodara)
Katsura Tree (Cercidiphyllum japonicum)
Chinese Fringe Tree (Chionanthus retusus)
Flowering Dogwood (Cornus florida)
Chinese (Kousa) Dogwood (Cornus kousa)
Winter King Hawthorn (Crataegus viridis ‘Winter King’)
Japanese Cedar (Cryptomeria japonica)
Leyland Cypress (Cupressocyparis x leylandii)
Persimmon (Diospyros virginiana)
American Beech (Fagus grandifolia)
European Beech (Fagus sylvatica)
Green Ash (Fraxinus pennsylvanica)
Ginkgo (Ginkgo biloba)
Honey Locust (Gleditsia triacanthos)
Carolina Silverbell (Halesia diptera)
American Holly (Ilex opaca)
Eastern Red Cedar (Juniperus virginiana)
Goldenrain Tree (Koelreuteria paniculata)
Tulip or Yellow Poplar (Liriodendron tulipifera)
Southern Magnolia (Magnolia grandiflora)
Dawn Redwood (Metasequoia glyptostroboides)
Eastern Hophornbeam (Ostrya virginiana)
Sourwood (Oxydendrum arboreum)
Spruces (Picea spp.)
Japanese Red Pine (Pinus densiflora)
Limber Pine (Pinus flexilis)
Eastern White Pine (Pinus strobus)
Flowering Cherry (Prunus serrulata)
Douglas Fir (Pseudotsuga menziesii)
Sassafras Tree (Sassafras albidum)
Bald Cypress (Taxodium distichum)

ShiShi Gashira Camellia So Far Holding Up to Zone 6-b Winters

Posted by Hugh on October 11th, 2013

'Shishigashira' Camellia in late October

Camellias bloom at a time when most trees and shrubs are not flowering. Growing them is no longer a dream for gardeners who do not live in the deep South. A number of “designated zone 6 hardy” cultivars prosper in the Southern Appalachian region (USDA hardiness zones 6 and 7). ‘ShiShi Gashira’ camellia (Camellia hiemalis) is not one listed in the zone 6 group.

Also written ‘Shishigashira’, it is a late fall blooming cultivar that grows 5-6 feet tall and slightly wider than high. Dark pink flowers are mostly 2 1/2 to 3 inches across and bloom from late October into early January. It is rated hardy in USDA hardness zones 7-10, but appears hardy in zone 6-b with protection. It does not bloom out its full bud count before sub-zero nights in December and January shut down flowering.

Foliage is evergreen and does not discolor over our cold winter months. It grows best with part sun or part shade, avoiding most afternoon sun. Dappled sunlight over most of the day will also suffice. Shishigashira is best protected from frigid wintry winds.

Newly planted camellias should be mulched and irrigated during dry periods until established in two years. Camellias dislike overwatering and have proven drought tolerance once established.

Camellia culture is similar to that of rhododendrons. Prepare the ground prior to planting, mixing in generous quantities of organic matter. Camellias require an acidic soil which is well-drained. Feed camellias with an acidic base fertilizer such as Miracle Gro™, Schultz™ or Hollytone™ every 4-6 weeks from March to mid-August.

Shishigashira makes a good fit in most urban gardens planted in a container (zone 7 and warmer) or as an evergreen foundation shrub.

Three New Hardy Fall Blooming Camellias

Posted by Hugh on October 10th, 2013

Camellia 'Long Island Pink'

Camellia 'Sweet October'

Three Zone 6 winter hardy camellias are becoming more available. A recent visit to a local camellia grower found these three fall bloomers: ‘Long Island Pink’, ‘Londontowne Blush’, and ‘Sweet October’ in full floral regalia. The first two are reliably hardy in USDA zone 6 and a third nearly so.

‘Long Island Pink’ was found growing in Long Island, NY. It produces bright pink single flowers and glossy evergreen foliage. Long Island Pink is a handsome 10 feet by 8 feet shrub, with a slightly upright habit. Flower color is medium pink.

‘Londontowne Blush’ bears semi-double pale pink flowers in mid-fall. This cold hardy C. sasanqua hybrid comes from Dr. William Ackerman, the camellia breeder who earlier introduced the ‘Winter” camellia series. It bears single to semi-double pale pink flowers with deeply notched petals. A 10-year old plant grows 5-6 feet tall and almost as wide.

‘Sweet October’ is another Ackerman cross (C. oleifera x C. sasanqua). This mid-fall blooming camellia bears single white flowers with a splash of pink. It possesses a vigorous growth rate (10-12 feet tall and 8 feet wide after 8-10 years). It tends to be upright branched and flowers in mid-to late fall.
Note: Sweet October is rated zone 7-a hardy.

Camellia culture is similar to rhododendrons and azaleas. Plant them in a compost rich, acidic, well-drained garden soil. In their first growing season camellias should be moderately watered and fertilized to develop a deep fibrous root system. After two years camellias exhibit moderate drought tolerance because of their thick waxy foliage. Overwatering is a curse.

Feed with an acid-based fertilizer (such as Miracle-Gro® or Hollytone®) after bloom. Keep roots cool and moist with a 2-3 inch layer of mulch.

Camellias are generally pruned after flowering. An alternative is to prune all cultivars at one time in late April when all flowering has ended and before new spring growth has begun.

Planting camellias in front of evergreen shrubs and trees offers an excellent background as well as protects them from dry winter winds.

Timing Fall Leaf Color Of Red Maple Cultivars

Posted by Hugh on October 7th, 2013

'October Glory' Red Maple in Mid-November in Tennessee

Red maple (Acer rubrum) is one of the most popular large street and shade tree in the Southern Appalachian region (USDA hardiness zones 6 and 7). Most cultivars average 40-60 feet tall in height.

Tiny red flowers burst open early, often before the official first day of spring. Flowers give way to reddish double winged samaras. Its glossy dark green 3-5 lobed leaves are 3-6 inches across with deep red petioles. Many red maple cultivars strut their vibrant red foliage on a specific week in October or November.

Red maple is native to moist well drained soils, preferably in full to partial sunlight. It tolerates wet soils and is unswayed by temporary flooding such as in rain garden zones. In some Midwest states it has earned the nickname “swamp maple”.

Red maple is also cataloged as “soft maple” because high winds and ice may break brittle branches. Its notoriously shallow root system may lift up adjacent sidewalks or driveways.

Red maple may be troubled by insect or disease problems, often when the tree(s) is planted on the wrong landscape site. Leaf aphids, wood borers and scale insects can be occasional pests. Verticillium wilt disease attacks the vascular system, frequently the result of unusually long dry spells extending three or more years. It is resistant to most common urban air pollutants.

Five popular cultivars planted in the southeast and mid-Atlantic states include:
Autumn Blaze® (A. x freemanii) – 50 ft. x 40 ft. – early deep burgundy red leaf color
Red Sunset® (A. rubrum) – 45 ft. x 35 ft. – early bright red leaf color
‘Autumn Flame’ (A. rubrum) – 35 ft. x 15 ft. – better red color in southeast U.S.
‘Armstrong’ (A. rubrum) – 45 ft x 15 ft. – columnar habit for narrow street plantings
October Glory® (A. rubrum) – 40 ft. x 35 ft. – one of the latest for red color

Pruning is best performed in the spring and summer months when sap pressure in low. Sap from this tree can be used to make maple syrup during the winter months.

Too Early Fall Color A Telltale Signal Of Tree In Trouble

Posted by Hugh on October 6th, 2013

'Red Sunset' Maples Coloring In Late September in Tennessee (photo by Ken Soergel)

Early leaf color or premature leaf drop often tells a property owner that their tree(s) may not be healthy. Photo above, taken in front of a new subdivision, says alot. Large red maples show leaf color weeks ahead of their natural timeline. Notice the narrow median where the trees are planted.

The cause of early foliage change may be weather-related, a foliar or root disease, an earlier insect infestation, or a site with one or more environmental factors. Extremes of either a dry or a wet summer (flooding) may lead to premature leaf drop or early fall leaf color. Urban air pollutants can be blamed.

In this landscape situation (photo), red maples were the wrong tree choice for the site. Red maple is nicknamed “swamp maple”; you find the species naturally growing along streams, and near lakes and ponds. Red maple has a notoriously shallow root system, a network of surface roots that destroy a home lawn or lift sidewalks.

In this example, on an obvious dry soil site, crape myrtle (Lagerstroemia spp.), sweetgum (Liquidambar styraciflua), elms (Ulmus spp.), Chanticleer pear (Pyrus calleryana), hornbeams (Carpinus spp.), or yellowwood (Cladrastis kentukea) would have been better tree choices.

A professional landscaper should have known that the tree choice was wrong. Unfortunately, mistakes like this are all too common.

Paperbark Maple Offers 4- Seasons Landscape Interest

Posted by Hugh on October 4th, 2013

In the winter some gardeners get excited about tree bark, particularly if you own a paperbark maple (Acer griseum). This small 25-30 foot tall tree has an upright spreading branching habit. The cinnamon-colored bark flakes off naturally in thin strips or chips. Horticulturists call this “exfoliating”. The sturdy branches are not prone to breakage in stormy weather.

Fall leaf color is variable. The foliage of select cultivars and some seedling forma turn scarlet red. The dark green trifoliate leaves present a fine texture to a summer garden. Spring flowers are mostly inconspicuous. Two winged samara fruits (many call them “helicopters”) start dropping in early fall. Most seeds do not germinate and create a weedy mess.

Plant in full sun in northerly hardiness zones 5 and 6, and protect from the direct afternoon summer sun in southerly zone 7. Paperbark maple prospers in moist, well-drained, compost-rich, and moderately acidic soil, but does adapt to average soil that are adequately drained. Water a newly planted tree regularly over the first two years until fully established. Paperbark maple is generally slow growing, often less than 12 inches a year.

Paperbark maple provides shelter for birds and other wildlife. It has no serious disease and pest problems when properly sited. Its slow growing nature rarely asks for pruning. Maintain a year-round mulch that’s 2 to 3 inches deep to maintain adequate soil moisture.

Location, Location, Location. Truly, it is in the fall and winter seasons when paperbark maple shines. Set paperbark maple where its exquisite trunk’s bark is on show all winter long. Consider landscape lighting as the tree ages and becomes grander.

Most paperbark maples in the marketplace are seedling forms, and may vary widely in bark color. Two noted cultivars include:
• Gingerbread® (‘Ginzam’) with darker cinnamon-red bark and orange-red fall color;
• ‘Cinnamon Flake’( A. griseum and A. maximowiczianum) features darker green summer foliage and exfoliating bark of tiny chips.

‘Halloween Hocus Pocus’ Daylily For Garden Goblins

Posted by Hugh on October 1st, 2013

'Halloween Hocus Pocus' daylily

On a pleasant July morning I saw my first ‘Halloween Hocus Pocus’ daylily (Hemerocallus x ‘Hocus Pocus’) in a friend’s garden. The 5 ½ inch flowers stand on 26 inch tall stems (scapes) and the foliage is semi-evergreen.

The cultivar name describes it best. Its creamy orange color with a triangular black throat and wide blacken edged petals are the perfect colors of Halloween. Flower throat is small and yellow green. Floral form is very round and full with petals overlapped. Petal substance is thick and smooth, and holds up well to full sun.

Flowers are borne on well-branched scapes and carry multiple blooms. Hocus Pocus is a vigorous grower and a mid-season bloomer. If properly watered and not subject to summer drought stress, it should re-bloom dependably in the late September into early October.

Flowers are similar to another Salter 2006 introduction ‘Halloween Trick’ which has plum color rather than blacken edges. In some catalogs it may also be listed as ‘Hocus Pocus’ and is classed as a tetraploid.

DOs and DON’Ts Checklist Before Purchasing Plants

Posted by Hugh on September 29th, 2013

Root Inspection of Japanese Maple

When shopping at the garden center don’t bring home problem plants. “Plants On Sale” should raise a caution flag. Thoroughly inspect all sale plants. They may have been sitting many months with the pots now full of weeds, diseases, or pest problems. They become tightly potbound and roots will need to be teased apart prior to planting. Some of my worse garden weeds got their start from a purchased plant. Nutsedge and oxalis are two of worse to bring home.

Inspect the underside of leaves for bugs. If the pots are easy to lift weight-wise, pop the pot off and look for live roots. Root rot diseases like Photophtora and Pythium can seriously kill roots of holly, rhododendron, azaleas, junipers in containers.

Not all roots are white-colored, but should appear plump and moist. The potting soil (media) should not contain dry patches. The media has lost its ability to hold water (“hydrophobic”). If you’re purchasing 10 or more plants, inspect 2 to 3 items.

Once home, isolate all suspicious plants for 1-2 weeks prior to planting. Recent warnings about boxwood blight should raise your concern. Boxwood blight is primarily spread from newly purchased boxwoods that introduce the disease to an existing planting. Daylily rust is started in much the same matter. It is carried from new daylily purchases.

One final point! Some percentage of plant roots growing in black nursery containers may be dead. The side of the pot facing the sun (outside rows) is where to inspect. Black containers absorb excessive solar heat, usually on the west-facing side, and roots frequently die. When purchasing plants, select plants from inside and not on the edge of the block. Similarly, winter cold temperatures may kill roots on the exposed sides of overwintering containers.

Tropical Flowering Maple

Posted by Hugh on September 26th, 2013

Chinese Parasol Tree Is Colorful Tropical

(Abutilon spp.), often called Chinese lantern or Chinese parasol plant, is a tropical houseplant (USDA hardiness zones 8-10). It offers pendant umbrella-shaped flowers along with handsome rich green five-lobed maple-like foliage. Some variegated leaf forms are available. Leaf petioles are long.

Utilize as a tropical foliage plant in the garden or a container. The brightly colored flowers are stunning. A pot plant often blooms earlier than one planted in the ground. The blooms attract hummingbirds and other pollinating insects. Some varieties are slightly cold hardier (zone 7-b), but this is no guarantee. The over-wintered plant outdoors seems to take most of the summer to struggle back and re-bloom.

Many hybrid varieties originate from Asia, Africa, and South America. Flowering may occurs in all four seasons, indoors as well as out. High light and warm temperatures of summer are mostly to their liking. For optimum growth and bloom, flowering maple needs high light from a south or east facing window and 68-72 °F minimum room temperatures.

Repot in April or May before moving outdoors in the garden. Move back indoors when night temps drop below 40 °F. Flowering maple grows exceptionally fast to 6 – 8 feet in height from spring to fall.

Follow a weekly watering schedule to establish a deep, extensive root system. Feed with a water-soluble fertilizer such as Miracle-Gro™, Jack’s™ or Daniels™ monthly at half the package rate during the spring, summer and fall months. Feed sparingly over the winter.

Prune twice annually in early spring and mid-summer to control plant size and shape. If the plant gets too leggy indoors, clip it back hard to increase branching. Flowering maple is frequently plagued by pesky whiteflies. Inspect your plant(s) for bugs before bringing indoors in the fall.

Flowering maple is easily propagated from cuttings and from seeds. Some plants may live 10 years and older and develop a 3 to 4 inch wide trunk.