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

Asian Pears Becoming Very Popular

Posted by Hugh on January 6th, 2016

‘Korean Giant’ Asian pear

Whether home-grown or store bought, Asian pear (Pyrus pyrifolia) fruits ripen sweet and tasty on the tree (USDA hardiness zones 4-9). There are over 100 varieties available worldwide, many with difficult to pronounce.

Investigate variety cold hardiness and winter chilling rating as some cultivars are hardier than others. Southern varieties require only 300- 600 hours of winter chilling temperatures (under 45°F) to set a crop annually. They ripen on the tree (ready to eat) compared to European pear varieties that are first harvested and ripened off the tree.

Asian pears trees bear fruits in 2-3 years compared to European pears in 4-5 years. Plant bare root trees either in late winter or in early fall. You will need to plant two or more different varieties to insure good cross pollination. Trees should be set 12-15 feet apart in a well-drained, moderately acidic soil; keep the graft union 2-4 inches above ground.

Trees should be pruned during late winter. Asian pears exhibit different growth habits than European pears. Asian pears are smaller trees (usually 8 feet to 12 feet tall). Some branches develop very narrow crotch angles, which may break under a heavy crop load.

Trees should be trained to a modified leader system. At planting, cut back the central leader to 36-42 inches above the ground to encourage lateral shoots. These shoots become the main scaffold branches. Remove any broken, low branches and root suckers at any time.

Do not fertilize newly planted trees in year one. Going forward, fertilize trees annually with granular 10-10-10 or equivalent. Keep trees mulched around the base. Loosely wrap chicken wire or mesh around trunk of newly planted fruit trees to protect the tender bark from rabbits and field mice (voles). The wire should be removed after two years.

Asian and European pears have their share of disease and pest problems. Consult fruit spray guides published by your state land grant university. Some Asian pears varieties are more disease resistant than others. Unfortunately, both Asian and European pears are susceptible to fireblight.

Depending on variety and growing region, Asian pears are ready for picking from mid-July to early-October. Fruits are thin skinned.

Fall Anemone 2016 Perennial Plant of The Year

Posted by Hugh on January 3rd, 2016

‘Honorine Jolbert’ anemone

Anemone at Biltmore Estates in Asheville, NC

Japanese anemone (Anemone x hybrida), popularly called “fall anemone”, are long-lived, fall-flowering perennials for cottage and open woodland gardens. They start to flower in late summer in many parts of the U.S. (USDA hardiness zones 4 to 7). Several colorful varieties are available. Fall anemones make great additions to cut floral arrangements.

For nearly 5 weeks, showy 2-4 inch wide flowers stand 2-4 feet tall (depending on variety), on long wiry stems above dark-green basal mounds. Anemones tend to be floppy and may need staking. Each flower is composed of 6-9 overlapping white petals with numerous yellow stamens in center. The dark green leaves are 3-lobed. This long-lived perennial spreads vigorously via creeping rhizomes and seeds.

Fall anemones prefer moderately moist soils and perform poorly on dry sites. They’re best sited in partially shade locations. Foliage tends to burn in hot, dry, sunny conditions. They fail in wet clayey soggy soils over winter. Plants may be slow to establish, but, once established, will aggressively naturalize, spreading by rhizomes to form large colonies. They can be propagate by root cuttings in winter (perhaps most effective) or by division in spring.

Fall anemones prefer partial sun to partial shade, never in full day sun or deep shade. At planting time, add lots of compost to a well-drained, mildly acidic garden soil (pH 5.5 to 7.0 range preferred). Plants are mostly deer tolerant and have few disease and insect problems. From the Greek, the word anemone means “windflower”; shelter plants from extreme winds. Anemones seed in readily (think weedy).

Special note: ‘Honorine Jobert’, an heirloom hybrid anemone popular in France since the mid-19^th century, has been designated the 2016 Perennial Plant of The Year.

Cultivars to try:

‘Honorine Jobert’ (2-3 inch single white flower)

‘Queen Charlotte’ (3 inch semi-double pink flower)

‘September Charm’ (3 inch single rose-pink flower)

‘Whirlwind’ (4 inch semi-double white flower)

Invincibelle Spirit Hydrangea Raises Money For The Cure

Posted by Hugh on December 31st, 2015

Hydrangea ‘Invincibelle Spirit’ in Conlon Garden

Since the introduction of the Invincibelle Spirit® hydrangea in 2009, sales from this special plant have raised funds for The Breast Cancer Research Foundation® (BCRF). At the end of 2015, fundraising efforts reached over $900,000 toward its million dollar goal. In addition to donating one dollar for every plant sold, it serves as the heart of hundreds of Pink Day fundraisers hosted at garden centers across the United States and Canada.

Proven Winners® ColorChoice®, the brand behind Invincibelle® Spirit hydrangea, selected The Breast Cancer Research Foundation (BCRF) because it is the highest rated breast cancer organization in the U.S. with an A+ rating from Charity Watch and 4 out of 4 stars from Charity Navigator. BCRF provides critical funding for cancer research worldwide to fuel advances in tumor biology, genetics, prevention, treatment, metastasis and survivorship.

New to the campaign in 2015 was the introduction of Invincibelle Spirit® II hydrangea. This new variety improves upon the original Invincibelle® Spirit while continuing the legacy of donating one dollar from each plant sold to BCRF. The Invincibelle Spirit hydrangeas (H. arborescens) is the result of the breeding of Dr. Tom Ranney, NCSU Ornamental Plant Breeder. This new hydrangea improves upon the original with brighter flower color, stronger stems, and superior performance in containers. Like its predecessor, Invincibelle Spirit II hydrangea is a reliable re-bloomer that will perform from Manitoba to Mobile (USDA hardiness zones 3-9).

Smooth hydrangea (Hydrangea arborescens) is a loosely branched deciduous shrub that typically grows to 3 – 6 feet tall and wide in the wild. This native shrub is easy to grow in average, moisture, well-drained soil in partial sun to shade. Invincibelle® Spirit hydrangea series is more compact at 3-4 feet in height and width. Irrigate shrubs during dry periods to keep summer foliage looking fresh. It flowers on new wood from late spring thru early summer.

Credit: data on sales of Invincibelle® Spirit hydrangeas provided by Mark Osgerby, Spring Meadow Nursery, Inc.

House Plants Purify Indoor Air

Posted by Hugh on December 30th, 2015

Snake Plants (Sanseveria)

Rubber plant (Ficus)

Yes, house plants do indeed clean, filter and purify the air of various toxins and pollutants. Back in the 1980’s the National Aeronautics and Space Administration (NASA)conducted tests to determine the best house plants that helped purify indoor air in homes and work environments.

If humans were to traveled to inhospitable planets, humans would inhabit biospheres full of plants scrub the air and supply life giving oxygen. NASA proved plants could remove volatile organic chemicals from the air, including formaldehyde, tobacco smoke, and some toxic gases. Some pollutants were shown to be dangerous to human health, including some found to be carcinogenic.

Over 50 species were identified, including some popular gift giving plants like poinsettias and kalanchoes. Below is a list of twenty (20) foliage house plants that people maintain in their home and office environments.

List of 20 House Plants

Bromeliad

Philodendron vines (Philodendron)
Pothos vines (Epipremnum)
Arrowwood vine (Syngonium podophyllum)
Weeping Fig (Ficus benjamina)
Rubber Plant (Ficus robusta)
Schefflera / Umbrella Plant (Schefflera)
Snake plant / Mother-in-Law’s Tongue (Sansevieria)
Dumb Cane (Dieffenbachia)
Corn Plants (Dracaena)
Prayer Plant (Maranta)
Thanksgiving or Christmas Cactus (Schlumbergera)
Spider Plant (Chlorophytum)
Peacock Plant (Calthea)
Chinese Evergreen (Aglaonema)
Boston Fern (Nephrolepis)
Peace Lily (Spathiphyllum)
Anthurium (Anthurium)
Bromeliad (Aechmea)
Moth Orchid (Phalaenopsis)
Norfolk Island Pine (Araucaria)

Arrowhead Vine- Easy Care House Plant

Posted by Hugh on December 27th, 2015

Arrowwood (Nephthytis) Vine

Arrowwood vine in Biltmore Conservatory, Asheville, NC

Arrowhead vine (Syngonium podophyllum), often called nephthytis, is a easy to grow trailing or vertical climbing house plant. It is indigenous to the Central and South America tropics and is botanically related to philodendron. Its 5-7 inch long leaves are arrowhead shape, with a dull pointed tip (apex) and two basal lobes. Foliage of modern day varieties come in more color choices, including silvery white, cream, and pale pink variegation. Plants grow more compact and foliage is disease resistant.

Arrowhead tolerates low winter light inside the home. Grow in a east facing window with room temperatures between 60-75°F and with moderate room humidity. Plant in a potting media having good drainage and keep media moist. Water less frequently in winter and periodically mist the foliage. Every 1-2 years, repot in early spring so plant never becomes root-bound.

If moved outdoors over the summer, keep arrowhead vine under heavy tree shade and adequately watered. In early fall move all tropical plants indoors before night temperatures fall below 40°F. From spring through fall, feed plant(s) every 2 weeks with a balanced house plant fertilizer such as Peters®, Daniels®, or Miracle-Gro® diluted by half the recommended package rate; do not fertilize over the winter months.

Arrowheads are constantly growing new leaves and shedding older ones. Prune out old straggly shoots and dying foliage at any time. At start of summer, cut older vine(s) back at least by two-thirds to refreshen their appearance. Use prunings to start new plants. To propagate, take a terminal stem tip cutting or stem segment containing a healthy node, leaf and petiole.

Newly purchased plants start out trailing. Within 6-12 months some developing stems turn upright and are easily trained as a climbing vine to a pole fashioned from osmunda fiber.

Caution: Sap of this plant may be toxic to pets and cause skin irritation. Wear protective gloves when working with arrowhead vine.

Care of Holiday Cactus

Posted by Hugh on December 25th, 2015

Thanksgiving cactus

Thanksgiving cactus for sale

Thanksgiving cactus (Schlumbergera truncata) and Christmas cactus (S. bridgesii) are popular fall- and winter-flowering houseplants. Flower colors (by variety) include red, purple, lavender, cream, and white.

Holiday cacti thrive in hanging baskets. The scalped stems and foliage start out growing vertically and weeks later begin to spill over the edge of the pot. Plants flourish for many years if these simple care tips are followed.

Fall-Winter Care In Your Home: Place in bright light in an east or south facing window for maximum flower numbers. Avoid cold, drafty areas close to window or near a dry heat source. Increase room humidity by sitting the pot on a tray of moist gravel, but do not allow bottom of container to stand in water.

After bloom finishes, prune back stems to develop a bushier plant. Feed monthly with a water soluble fertilizer such as Miracle-Gro™, Peters™, Nature’s Source™, or Schultz™ at one-half package directions.

Spring-Summer Outdoors: Move plant outside once night temperatures remain above 45°F. Avoid placing cactus in direct sunlight. Over the first 1-2 weeks, acclimate the plant to outdoor temperature, light, and wind. If leaf edges start to redden, move plant to a shadier spot. Increase frequency of watering, particularly when rainfall is lacking.

Feed holiday cactus every 2-3 weeks with a water soluble fertilizer at full label rates. This is during the periods of active spring/summer growth and full bloom indoors.

To Initiate Holiday Blooms: In early to mid-October, place cactus in the dark for 12 hours daily, such as in a closet from 8 p.m. to 8 a.m. over 6 to 8 consecutive weeks. An alternative method is to chill the plant in temperatures between 50 – 55°F at night. This may be done outdoors, weather permitting. Don’t subject plant to temperatures below 40°F.

Holiday cacti are not desert cacti, but true epiphytic succulents that live in the shade of Brazilian tropical rain forests. They have high water and humidity needs. Drought is taboo to these plants; drought symptoms include shriveled scalped leaves and blooms and buds drop off. Plants need to be watered regularly, at least weekly. Plant(s) should be repotted annually, usually in March, into a larger pot containing a well-drained potting media, preferably one designated for succulents. After potting, prune the plant back by at least one-half and encourage good branch symmetry around pot.

American Holly For Year-round Interest

Posted by Hugh on December 22nd, 2015

Century old Ilex opaca at Biltmore Estate, Asheville, NC

American Holly (Ilex opaca) is a pyramidal evergreen tree that deserves to be planted more for multiple reasons. It is native to the eastern and central U. S. and is easily identified by its spiny green leaves (USDA hardiness zones 5 to 9).

It grows slowly to 15 to 35 feet, sometimes taller. The leathery, deep green leaves (2-4 inches long) are spiny-tipped along the leaf margins. Hollies are dioecious, e.g. individual plants are sexed either male or female.

Greenish-white flowers appear in May-June. Bright red or golden yellow ¼ – ½ inches diameter drupe fruits (“berries”) ripen on female trees in fall and persist on the tree through winter. For good fruit set male and female hollies needed to be planted within ½ mile apart.

American holly grows in any average soil, but fails in poorly drained or soils that periodically flood. In northern zone holly grows in full day sun and prefers partial afternoon shade in southern region (7b -9). In early spring feed a slow-release fertilizer specifically labelled for acidic loving plants.

Holly foliage and berries are used for winter holiday wreaths and other decorations. The tree provides shelter for birds from harsh weather and predators; holly berries are a steady food source all winter long. Spiny leaves contain toxic sap and are an adequate deterrent against deer.

American hollies are susceptible to leaf drop, leaf scorch and chlorosis (leaf yellowing in high pH soils). When properly sited, hollies have few disease and insect problems. Otherwise, the list of potential problems grows long.

Utilize as a single tree specimen or group several for foundation planting and for hedging. Foliage and fruits are superior winter features.

Over 100 cultivars of American hollies are identified and cataloged. Five exceptional cultivars are:

‘Dan Fenton’– broad pyramidal form to 25 feet high; dark green leaves and shiny red berries.

‘Jersey Princess’– female pyramidal form with glossy dark green leaves, and bright red berries released from Rutgers University.

‘Jersey Knight’– male pollinator for ‘Jersey Princess’ with dark green leaves (another Rutgers introduction).

‘Satyr Hill’– vigorous grower, upright pyramidal habit, olive green foliage, and bright red berries.

‘Xanthocarpa’– pyramidal form and yellow-orange berry fruits.

Growing Calamondin Orange

Posted by Hugh on December 18th, 2015

Calamondin orange (Citrofortunella mitis)

Calamondin (Citrofortunella mitis) hails from China and is hardy to 20 ºF in temperate regions. It prospers outdoors in Florida, central and southern Texas, and Southern California gardens. Its sweetly fragrant flowers develop into edible ornamental fruits beginning in late fall. Small 1-2 inch diameter orange fruits are highly decorative as an indoor house plant.

Calamondin can be grown in a large tub or portable container plant in colder regions where do not commonly grow. It thrives in bright light near a window for best growth and fruiting, but will tolerate lower light levels in winter. It is the most popular potted citrus, along with Meyer lemon and Ponderosa lemon. It performs well as a summer patio plant; it may be trimmed as a hedge in warm zone 8 and further south.

Water plants as needed; excess or lack of water will kill calamondin. Repot your plant in mid- to late winter. Add a slow-release fertilizer such as Osmocote™ to the container in early spring and continue fertilizing with full strength water-soluble acidic fertilizer (Miracle Gro™ or Peters® 20-10-20 or Schultz®) monthly over the summer and early fall. Fertilize sparingly during the winter months using one-half strength water-soluble fertilizer every 4-5 weeks.

Calamondin may bloom 4-5 times a year. The spring growth flush often produces the most flowers. The flowers are self-fertile and require no cross-pollination. Flower and fruit often will appear at the same time. Calamondin fruits take nearly a year to ripen.

Fruits are thin skinned and have short keeping life of 1-2 weeks after picking. If you eat the fruit, choose firm yellow to yellow-orange fruits. Use pruners or scissors to harvest off the tree instead of pulling them. Prune calamondin in late winter before the spring growth flush. Most cuts are for shaping and size control. Remove dead or damaged twigs at any time.

Plants should be inspected for mites, mealy bugs, scales, and aphids every few weeks; particularly check the underside of leaves. Insecticidal soaps and neem oil are effective in managing pest outbreaks.

Re-blooming Your Poinsettia

Posted by Hugh on December 14th, 2015

Poinsettias for Sale

Many people like to save their poinsettia plant and re-flowered it next Christmas. Scheduling a poinsettia to re-bloom is not difficult, but you need to follow an exact year-long procedure. First, continue to water the soil in the pot until early April.

In April, cut the stems back to about 4 inches above the soil. Replant into a new container that is 1 to 2 inches larger in diameter, adding new soilless potting mix. Many good commercial potting mixes are available. Do not use soil from the garden as it may contain diseases. Water the soil thoroughly when the surface of the soil feels dry to the touch. Place the plant near a sunny window (east or southern exposure is ideal) and at temperatures between 65 – 75°F.

New shoots will appear within a few weeks. Start to fertilize every 2-3 weeks with a water soluble fertilizer such as Miracle-Gro™, Peters™, or Schultz™ according to package directions.

By mid-to late-May (if danger of frost in your area is low), move poinsettia outdoors in a lightly shaded location, such as under a shade tree for the summer. You may wish to submerge the pot in a hole so that it does not fall over on windy days. Continue watering and fertilizing the plant as needed through the summer.

Starting in early July, lightly pinch each stem (remove 1 inch of shoot tip) to encourage branching. In late August, add a second pinch, leaving 3-4 leaves on each shoot. After this second pinch, bring the plant indoors (or late September), and place it in a sunny window. Keep the plant at a temperature of 65 to 70°F at night and continue watering and fertilizing.

Poinsettias are short-day plants, e.g. they initiate flowers about 10 weeks after daylength shortens to 12 hours or less. This part requires your complete dedication: keep the plant in complete darkness between 5 p.m. and 8 a.m. from early October until Thanksgiving Day for a total of 6 weeks. During this interval, any kind of light exposure between 5 p.m. and 8 a.m. will delay flowering. Putting plant in a closet or covering with a black sheet are two popular options. Over the daytime hours move the plant near a sunny window and continue watering and fertilizing your poinsettia.

Happy Holidays!

Unique Life Cycle Of Bumble Bees

Posted by Hugh on December 13th, 2015

Bumble Bee pollinating

Bumblebee pollinating buddleia

Bumble bees (Bombus spp.) are highly beneficial insects that pollinate native wildflowers, fruits, vegetables, and many agricultural crops. They’re large robust insects with an easily identifiable black and yellow hairy abdomen. Hundreds of branched hairs pick up and transfer pollen from flowers. About 50 species of bumble bees inhabit North America.

They share some common traits with honey bees, which are not native. Both are highly social insects and live in colonies with one queen and many workers. Bumble bee colonies last less than one year compared to honey bees. They do not store a surplus of honey for harvested. Populations fluctuate from year to the next, subject to environmental factors, parasites and predators.

Bumble bees are ground nesters, making their colonies in mostly underground holes or a few above ground partly covered by debris. Their nests are larger than those of solitary bees. In early spring a young queen finds an abandoned nest or burrow made by another critter and prepares it for her brood. She builds a few wax pots that she fills up with pollen and honey, and a larger cell for her brood. She lays her eggs, laying no more than half a dozen at first. These eldest offspring are all sterile female workers. Once this brood is fully grown, the queen rarely leaves the nest again and spends all her time laying more eggs while the workers take care of all the activities in and out of the nest.

By midsummer the colony (nest) grows rapidly and will have 20-100 workers. Near summer’s end, the queen lays eggs containing fertile males and females. The females emerge from the nest and mate with males. All sterile workers, male bumble bees, and queen mother die at the end of summer. A mated queen hibernates 2-5 inches deep in the soil over winter and re-emerges found a new nest.

In some countries bumble bees are imported to pollinate specific crops such as forage clover (Trifolium pratense) in fields and tomato crops in greenhouses. They can fly at much lower temperatures than honeybees and can pollinate flowers with long, narrow corollas.

Source: several USDA publications on Bumble bees