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

Globe Amaranth (Gomphrena)

Posted by Hugh on April 1st, 2022

Three important objectives of area gardeners are: 1. Inviting more pollinators, 2. Growing more natives, and 3. Reducing garden maintenance. Gomphrenas, aka Globe amaranths, are becoming more recognized as outstanding annual flowering plants for Tennessee/Virginia/North Carolina gardens. Gomphrenas are North American natives (Texas, New Mexico, and northeastern Mexico) and are blooming machines in the heat, the humidity, and droughty soils of summer.

Gardeners often reach for showy big flowering annuals. However, small ball-shaped clove-like gomphrena blooms are covered with throngs of bees, butterflies, and other nectar feeders in garden beds and containers. Gomphrenas root down deeply and bloom spring, summer, and way into autumn, wanting very little care.

Gomphrenas grow 10 to 24 inches high and 12 to 16 inches spread. The color floral palette comprises purple, pink, orange-salmon, and red. They prosper in full sun and will grow in poor to average ground as long as soil drainage is good. Space plants a foot or so apart. Spread a slow-release fertilizer such as Osmocote™ at planting time. If leaves appear chlorotic in summer, apply a water-soluble fertilizer such as Miracle-Gro™ or Peters™ to green-up plants. Gomphrenas planted in the spring are usually well established in 4-6 weeks. Afterwards, summer watering needs are minimal.

Gomphrenas attract very few pests and disease problems. Rabbits and deer generally stay away. Spider mites are sometimes troublesome if summer weather is exceptionally dry. A coarse spray of water directed to the underside of leaves will reduce mite populations without use of pesticides.

So many great choices!! Long-stemmed Gomphrena haageana grow taller and not as wide as G. globosa. Distinctive G. globosa cultivars include: bright fuchsia ‘Fireworks’, stoplight red ‘Strawberry Fields’, and ‘Lavender Lady’. ‘Fireworks’ are described as “explosions of pink with yellow stamen flowers”. In 2020 a huge hit among visitors to the UT Gardens in Jackson was G. pulchella Truffula™ Pink with “tufted, hot pink orbs with the bracts tipped in tangerine”. It grows slightly smaller than ‘Fireworks’, another gardener favorite.

Audray™ series are available in Bicolor Rose, Pink, Purple Red, and White. LasVegas series (white, pink, purple) are also standouts. See Gomphrena photos on SAPS website. Gomphrena flowers are especially nice in mixed fresh floral bouquets for the table and in dried florist arrangements.

2022 Perennial Plant of the Year® Announced

Posted by Hugh on March 31st, 2022

2Since 1990 The Perennial Plant Association (PPA) has showcased a perennial that is a standout among its competitors! Perennials chosen for this honor are suitable for a wide range of growing climates, require low maintenance, have multiple-season interest, and are relatively pest/disease-free. Each year PPA members look at four nominated perennials and vote for their favorite. PPA members vote for the Perennial Plant of the Year® and nominate additional plants for the following year’s ballot. In addition, members have access to a flyer, poster, and bench card to assist with promoting the Perennial Plant of the Year®.

The PPA is pleased to promote Little bluestem (Schizachyrium scoparium and cultivars) as the 2022 Perennial Plant of the Year®. The wider selection of Schizachyrium scoparium and cultivars allows the perennial expert in any region to select and promote the cultivars that do best in his or her location!

PPA Board members selected top performers in their regions and shared appealing details about each one. Highlights of each selection are below:

Central region – Richard Hawke of the Chicago Botanic Garden selects Schizachyrium scoparium ‘Jazz’ for the Central region. Richard notes, “The striking silvery blue leaves of Schizachyrium scoparium ‘Jazz’ are most comparable to ‘The Blues’, but at 36 inches tall and 30 inches wide, ‘Jazz’ is a foot shorter than ‘The Blues’ and has sturdier stems.

Southern region – Shannon Currey of Hoffman Nursery selects Schizachyrium scoparium ‘The Blues’ for the Southern region. Shannon comments, “In the South, our humidity, high nighttime temps, and wet springs can slow down some Little Bluestem. ‘The Blues’ is a strong, vigorous grower and has fantastic color. Blues, pinks, purples in the summer followed by reds and oranges in the fall. In the right conditions, it stands out for us.”

Canadian region – Tony Post of Brookdale Treeland Nurseries – Valleybrook Farm, choses Schizachyrium scoparium ‘Standing Ovation’ for the Canadian region. Tony says, “This selection adds excellent texture to the summer garden. Burgundy highlights add late season interest. Seed heads are attractive, particularly when backlit.”

Western region – For the Western region, Nanci Hollerith Allen of MarkWatch Plants notes that Schizachyrium scoparium can be a tricky plant unless you have reasonably dry, well-drained soil. She shares two recommended cultivars for the Pacific Northwest and the Rocky Mountain region: Schizachyrium scoparium ‘The Blues’ and Schizachyrium scoparium ‘Standing Ovation’.

Great Lakes region – Patty Steinhauser of Stonehouse Nursery chooses Schizachyrium scoparium ‘Carousel’ for the Great Lakes region. Patty says that, “This uniquely mounded selection forms a wide clump of blue-green foliage that emerges nearly horizontal and matures into strong, upright stems that remain standing through inclement weather and winter. It takes on pink, copper and orange-red tones in fall topped with tiny seed tufts.”

Mid-Atlantic region – Taylor Pilker of Cavano’s Perennials suggests ‘The Blues’, ‘Standing Ovation’, and ‘Jazz’. Taylor likes ‘Blue Heaven’ because “it is taller and has good autumn color with a wide range of shades of burgundy and pink.”

Information source: Perennial Plant Association website

Coneflower Variety Trials At MT. Cuba Center

Posted by Hugh on March 26th, 2022

Echinacea planting at Kingwood Center, Mansfield, Ohio

Coneflowers (Echinacea spp) are immensely popular native flowering perennials prized for their summer floral beauty. Nine species of Echinacea are native in North America and are found primarily in the central and southeastern U.S. Additionally, some populations of Echinacea angustifolia extend from the U.S. northwards into southcentral Canada.

Since the 1990s, a boom in Echinacea breeding has resulted in large numbers of new cultivars arriving at garden centers. The result has been an endless array in diversity, particularly in plant sizes and flower colors of coneflowers.

In 2020 MT Cuba Center in Greenville, DE released their most up to date ratings. This represents an updated test summary from their previous 3-year Echinacea variety trial in 2007-2009. The new report lists many more coneflower introductions and compares some newer cultivars against some of the tried-and-true top performers from the 2007-2009 trial.

In addition, MT Cuba conducted a pollinator survey to determine the cultivars that were most attractive to pollinating insects. This data was collected by their Pollinator Observation group. They tallied insect visitation to help determine ecological value of plants in our trials. For Echinacea, special attention was paid to the difference between single and double flowers in their ability to attract pollinators.

The best performing coneflowers in the trial are E. purpurea ‘Pica Bella’, E. ‘Sensation Pink’, E. ‘Santa Fe’, E. ‘TNECHKR’ (KISMET® Raspberry), E. ‘Snow Cone’, E. ‘POST301’ (Postman), E. ‘Glowing Dream’, E. ‘Purple Emperor’, E. purpurea ‘Fragrant Angel’, E. ‘TNECHKIO’ (KISMET® Intense Orange), E. ‘Balsomcor’ (SOMBRERO® Hot Coral), and E. ‘Julia’.

Important to gardeners: if you live in the mid-Atlantic States, results from the MT Cuba trial should be most useful and are posted online on the MT Cuba website. Midwest gardeners should look to recent Echinacea evaluations at the Chicago Botanical Gardens.

Eight Colorful Annuals Thrive In Shade

Posted by Hugh on March 20th, 2022

1. Boston fern (Nephrolepis exaltata) are excellent shade plants, traditionally planted in hanging baskets and window boxes. Asparagus fern (Asparagus springeri) is also nice additions to shady areas.

2. Coleus (Solenostemon) are known for their colorful foliage is nice in a pot or around trees or shrubs. For moderately shady areas, select the Mosaic™ or Kong™ series.

3. Begonias as a group represent lots of variety series. Most garden begonia varieties should do well in beds, planters and pots. Begonia types like the Rex and Angel Wing are grown primarily for colorful foliage and secondarily for flowers.

4. Impatiens are not just for shady garden spots anymore. Choose hybrid disease resistant varieties such as Sunpatiens, New Guinea, and Beacon ™ (NEW in 2020) impatiens are full of bigger showy blooms and perform best in partially shaded areas.

5. Caladium are non-hardy tubers are often started indoors in late winter to extend their outdoor season. They are grown for their colorful tropical foliage which brightens up shady areas.

6. Fuchsias are readily identifiable by their drooping, brightly colored flowers that bloom most of the summer. Select the trailing habit which promise excellent flowering in beds or hanging baskets.

7. Wishbone flower (Torenia fournieri) bloom from late spring into early autumn. Summer Wave® and Clown series are current favorites; tolerant of heat, heavy rains, and occasionally dry soils. Plants usually get about 6 inches tall and can trail up to 30 inches.

8. Polka-dot plant (Hypoestes phyllostachya) grow 1-3 feet high with purple-green leaves that are ornately speckled in shades of pink and white leaves; these tropical, colorful shade plants thrive in hot and humid conditions; polka-dot plant is moderately drought tolerant. Seed series: Confetti™; Splash™.

Growing Tips: All eight shade annuals look great in the front of landscape beds or in large patio containers and hanging baskets. Plants are set in mid-spring when threats of frost have left the area. All prefer moist fertile loamy soil, and partial shade area. They tolerate heat and humidity and perform poorly in either full day sun or deep shade.

Snowdrops (Galanthus)

Posted by Hugh on March 16th, 2022

Snowdrops (Galanthus spp.) are one of the first of all spring flowers to bloom. Depending on the region, they appear in February and March, often while patches of snow is still blanketing the ground. Snowdrops belong in the small genus Galanthus, that contains approximately 20 species of bulbous perennial herbaceous plants in the family Amaryllidaceae. They are native to Europe and southwest Asia (USDA hardiness zones 3 to 7). Snowdrops are best suited to cooler climes and bulbs often lose vigor in the South.

Two popular species are G. elwesii, called the “giant snowdrop” and grows to be twice as tall as the common snowdrop (G. nivalis). Common snowdrops are 3 to 6 inches high (7–15 cm). A white “drop” flower is supported by a stalk comprised of three outer petals above three inner petals. Narrow bladed (linear) leaves are about 4 inches long. As perennials, snowdrops divide and spread freely by offsets. The plants have two linear leaves and a single small white drooping bell shaped flower with six petal-like tepals in two circles. The smaller inner petals have green markings.

Plant the bulbs 2 to 3 inches deep in the ground, in groups of 10- 20 or more bulbs in early fall. Snowdrops are small plants that don’t make much impact individually, so create a showy display by planting in multiples. Create a blanket of snowdrops that cover an area. Plant under deciduous trees and shrubs, rock gardens, border frontage, or in front of flowering shrubs, or in lawns or along woodland paths. It prefers moist, humus-rich soils, partial shade, and cooler climates. Snowdrops are listed hardy in zones 4-7, but are seen in zones 2 and 3.

Over the years drifts of grouped bulbs gradually spread. You can also mix the planting with other spring-blooming bulbs. You can plant snowdrop bulbs under deciduous trees that permit sufficient sunlight to penetrate and nourish. Provide good soil drainage and bright shade.

Snowdrops have no serious disease or pest problems. Snowdrops are found in a woodland or rock gardens planted with other late winter blooming bulbous favorites: glory-of-the-snow (Chionodoxa), crocus, winter aconite bulbs (Eranthis hyemalis), spring snowflake (Leucojum) and others.

“Snowdrops are critter-proof”, according to Brent Heath with Brent and Becky’s Bulbs in Gloucester, VA. Deer, rabbits, chipmunks, and mice do not trouble them. They are poisonous to humans and pets (dogs and cats). Do not allow pets or children to eat them. Wear garden gloves when planting bulbs to avoid skin irritation.

Snowdrop flower bulbs are small bulbs that should be planted immediately after purchase. Bulbs dry out quickly sitting around for weeks in the house or in dry soil.

Five Redbuds With Dynamite Seasonal Foliage

Posted by Hugh on March 11th, 2022

Here are five notable redbuds (Cercis canadensis) possessing colorful summer foliage. Of note, the first 3 of 5 varieties are the creation of noted plant breeder Dr. Dennis Werner of NC State University in Raleigh.

Flame Thrower® has stunning eye-catching foliage color breakthrough in the world of redbuds. It is marketed as Eternal Flame® in Europe. Its stunning color foliage is on fire throughout the season, offering hues of reds, oranges, yellows and greens along the branches. The intensity of colors changes throughout the season with reds and oranges more prominent in spring, followed by yellows and greens in summer.

Clusters of pink blooms emerge from buds on branch wood and twigs in early spring for added garden appeal. The tree matures to 15 to 20 feet.

Carolina Sweetheart® has a rounded crown and typically matures to 20 to 30 feet tall with a slightly larger spread. A carnival of color in early summer as new leaves emerge, ‘Carolina Sweetheart’™ redbud starts out with pink flowers in early spring. New leaves emerge purple, but over time, they gain various shades of white, green, and hot pink. Eventually, the leaves turn green in the summer.

‘Whitewater’ combines a more vivid form of variegation with a broadly weeping habit. The pea-shaped flowers bloom in April and May, are a deep rose-purple. Flowers are quickly followed by the heart-shaped leaves which emerge mostly white with green flecks and mature to mostly green with white flecks. The weeping habit is an exciting addition to the bright variegated foliage.

‘The Rising Sun’ is semi-dwarf tree (8 to 12 feet tall). New heart-shaped deep apricot leaves age, starting out in peach, next to vivid yellow, then chartreuse, and finishing deep green. Light magenta blooms coat the tree’s round canopy in early spring.

‘Alley Cat’ is a 20 by 20 feet redbud with foliage liberally splashed with white. Its striking variegation is stable and scorch resistant. The dark pink pea-shaped flowers emerge in April just before the leaves; summer foliage shades of copper pink and soft green are showy. As the foliage matures, the white emerges and makes a lovely contrast to the green.

Our native redbuds prosper in full sun to partial shade (zones 5 to 9). While at their best in full sun, some varieties may benefit from some afternoon shade in hot Southern climes. Redbuds prefer average to moist well-drained soils. Avoid droughty and poorly drained soils are not particular as to soil type or pH. The foliage is highly tolerant of urban pollutants. Annual mulching around the root zone is beneficial.

Bigleaf Magnolia

Posted by Hugh on March 6th, 2022

Bigleaf magnolia (Magnolia macrophylla) is a deciduous, native tree that reaches 30-40 feet tall. This unusual pyramidal tree magnolia is rarely found in the wild, inhabiting a few rich wooded areas in river valleys in the southeastern U.S. (USDA hardiness zones 5-8). With age, the tree develops a spreading rounded crown.

Bigleaf magnolia is a unique landscape feature. This deciduous magnolia bears the largest flowers of any tree in North America. Its enormous-size mature leaves are green above and silvery-gray below that can be up to 36 inches long and 12 inches across. You find the tree growing in cool moist mountainous habitats and in mildly acidic soils.

The cream-colored goblet-shaped blooms open to 8-10 inches across, and emit a delightful fragrance up close in late May. After flowering, the seed pods swell with seeds covered in a protective red seed coat.

Cultivars are rare – ‘Palmberg ’ (with slightly larger flowers) and ‘Purple Spotted’ (flowers with purple stain at their base). For most people the place you see the first bigleaf magnolia is at a regional botanical gardens in the Mid-Atlantic and Southeastern U.S.

The huge flowers are often located far off the ground and are not always easy spotted from the ground. Flowers give way to spherical cone-like fruits which mature to red in late summer, releasing individual red coated seeds attached to slender threads.

Its large foliage limits its use in many urban landscapes. Bigleaf magnolia grows best in moist, organically rich, well-drained loams in full sun to part shade. Generally intolerant of soil extremes (dry or wet) as well as most urban pollutants. Best sited in locations protected from strong winds which may shred the large leaves.

For the patient gardener, the tree likes to get its roots established before adding on lots of vegetative shoot growth. The first blooms may not appear for 12 or more years. Bigleaf magnolia is hard to purchase in the garden marketplace. Search for young seedlings at native plant emporiums online.

Landscape Site: moist woodlands

Ridding Homes Of Camel Crickets

Posted by Hugh on February 26th, 2022

Camel crickets, also known as cave crickets or spider crickets live in dark damp places of the home or garage. They are related to grasshoppers, locusts, and other crickets (insect order Orthoptera) and are six legged as opposed to spiders that have eight legs. Fully grown adults range in size from 1-2 inches long, while the nymphs, the immature stages, have the same body type at a smaller scale, and no wings.

Camel crickets are strong jumpers, thanks to their long hind legs, and do not have wings. Camel crickets do not bite and their chewing mouthparts gnaw on just about anything, including fabrics, wood, cardboard, plants, and other bugs.

Camel crickets are often seen in eastern and Midwest states. These pests dislike the cold damp and tend to make their way indoors when the weather is hot and dry in the summer and fall months. They can breed in your house if the conditions are right, and may be seen any time of year. They will feed on fungi, wood, cardboard, fabrics, and other spider crickets.

Prevention and eradication of spider crickets is to keep them out of your home in the first place. Basements and crawl spaces are popular hangouts for them. Seal around entry doors and basement windows and ground-level doors with weather stripping. Dehumidifiers make room air less damp. Toss away old cardboard boxes and newspapers will also help.

Sticky insect traps are available at home stores. You can make your own from a few loops of duct tape. Place these where walls and floors intersect in basements and attached garages. Shallow bowls of soapy water also make effective traps. Camel crickets will fall in the bowl and drown. The key method of managing these household pests is to reduce the moisture inside your home. They are attracted to water and high humidity.

Use a shop vacuum to suck them up and empty it out immediately. Otherwise, they will crawl out and re-infest your home.

Hardy Zone 6 Camellias

Posted by Hugh on February 21st, 2022

In the Southern U.S., camellias are treasured for their showy flowers in the fall-winter landscape. Their glossy evergreen foliage looks great all year long. Hardy varieties are now available for zone 6 northern gardens (-10 to 0 °F). Essentially, gardeners can raise camellias in Tennessee, Kentucky, Virginia and in most coastal cities along the East Coast. Blooms measure 3-5 inches across with yellow stamens in the floral centers.

Depending on variety, flowering may last for a period of 4 to 6 weeks. Sudden drops of temperatures may injure blooms currently opened and those due to open a few days; hence, flowers in tight bud often survive, swell, and open. Color choices include shades of red, pink, lavender, white and even multi-colored. Varieties vary in size, from 8 -15 feet in height and 6 – 10 feet in spread. Spring pruning can alter plant dimensions.

Camellia likes a well-drained, mildly acidic soil along with adequate soil moisture. In northern areas grow shrubs in a partially sunny location or one with full morning sun and afternoon shade. Established camellias are moderately drought tolerant; irrigate during prolong dry spells in summer and fall. Fertilize camellias in early spring with a product labeled for acid-loving shrubs. Prune camellias after seasonal blooming is over or in mid-spring.

Shishi Gashira camellia is an outstanding flowering shrub. Looks-wise, in leaf and flowering, this camellia mimics our Sasanqua camellias, but is actually Camellia hiemalis. It has a mature compact height of only three feet. and is an ideal choice for smaller landscapes. Foliage is highly glossy and leathery along with gorgeous semi-double, rose-pink blooms. Shishi Gashira is a winter bloomer with great cold tolerance.

‘Cleopatra’ camellia blooms in October – November

Modern day zone 6 camellias are interspecific crosses between C. oleifera, C. sasanqua, C. hiemalis, C. japonica, C. vernalis selections. Some start blooming in early fall into very early winter and a second flower in March and April. Petals are shed and require no dead-heading. In northerly climes, zone 6 hardy camellias should be planted and mulched from early spring up to Labor Day (and no later).

Reward yourself by planting two or more camellia in your garden to flower during the transition period in early fall and in late winter when temperatures are seasonally mild. Here are some favorites:

Fall Bloomers: ‘Snow Flurry’ (white), ‘Autumn Pink Icicle’ (clear pink), ‘Sweet October’ (white / pink tinge), ‘Winter’s Joy’ (pink double), and ‘Long Island Pink’ (light pink), ‘Cleopatra’ (soft pink).

Mid-March/April Bloomers: ‘Pink Icicle’ (shell pink), ‘April Tryst’ (deep red), and ‘April Remembered’ (pale pink-large flower), ‘April Rose’ (deep rose pink).s

Uniqely Different Chinese Quince

Posted by Hugh on February 16th, 2022

Chinese quince (Pseudocydonia sinensis) is an under-utilized small 10-20 feet tall deciduous tree or large shrub with a dense oval crown (USDA hardiness zones 5-8). Initially, it starts out a slow grower for 1-2 years to establish its roots. Throughout the year, it provides several months of landscape charm that includes an attractive form, large edible fruits, and a stunning patchwork bark in fall and winter.

Chinese Quince (Pseudocydonia sinensis) at NC Arboretum Bonsai Collection

The finely edged, oval shaped, 3-4″ dark green leaves emerge in late March and April. The foliage stays blemish-free through summer and turns yellow to red in fall. Showy cup-shaped, fragrant pink flowers (to 1 1/2″ across) bloom in April-May. They resemble the blooms seen on the more popular Japanese flowering quince (Chaenomeles speciosa).

Huge (5 – 5½” wide) oval quince fruits ripen in fall (October) and are sweetly fragrant in aroma. Fruits are edible off the tree and can be made into jams and syrups. Unpicked fruits may become a trashy headache. Ripen fruits fall from the tree, break open, and rot. The decaying fruits emit a foul odor that attract wasps and other insects.

During the remaining autumn and winter season, your eyes will delight at the tree’s patchwork bark. The flakey, sycamore-like trunk exfoliates to expose brown, orange, green and gray hues.

Chinese quince is a good planting choice in small landscape places. It is easily grown in average well-drained soils and in full sun. The tree tolerates poor soils and moderate drought, but prefers fertile, moist, well-drained, mildly acidic loam soil. Site in winter protected locations (southern side of walls) in the northern part of its zone 5 growing range.

Chinese quince is available primarily from specialty nurseries online and generally not sold at local garden centers.

Fireblight can be a serious disease problem in areas of the U.S. in some years.