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

Abyssinian Red Banana

Posted by Hugh on October 18th, 2022

Ensete ventricosum is not true banana (Musa spp ); it does not sucker like bananas, so does not form large clumps over time. In their native environment in tropical Asia and Africa, plants may grow to 30 or more feet in height, but grow considerably shorter in containers or in cultivation.

Abyssinian Red Banana (Ensete ventricosum ‘Maurelli’) is a tropical plant from East Africa that should spark up your landscape. (USDA hardiness zones 10-11). The cultivar ‘Maurelii’ flaunts huge attractive colorful leaves. Each leaf emerges with maroon-reddish hues and reddish leaf axils. With a maximum height between 7-10 feet, it is smaller in height than many Musa banana varieties.

Amend the soil if needed with 3 to 4 inches of compost or humus. Water generously over dry periods. Feed annually with a slow-release fertilizer like Osmocote™ or Nitricote™. An alternative nutrition program is monthly feeding with a water-soluble fertilizer like Miracle-Gro™ or Espoma™ during the spring and summer months.

‘Maurelii’ Ensete Banana at Cincinnati Zoo

Grow in full day sunlight in zones 5b thru 7 and partially shade in the afternoon in the deep South (zones 8-11). Sunlight is important for gorgeous leaf and petiole coloration. Plant performs best in a sandy, organic-rich, well-drained soil. Keep the plant well-mulched to conserve soil moisture. Bananas like lots of moisture. Trim leaves as needed to keep the plant attractive.

Move your Red Abyssinian Banana Tree indoors in fall if you live in a zone colder than Zone 8. Repot into fresh compost-rich potting media, trim back roots, and cut back leaves and petioles. Store in a cool spot around 40°F until spring.

Most likely, your Ensete or Musa plant was purchased from the garden center and originated from tissue culture. The plant is not likely to flower outdoors in zones 6 and 7, and the fruits are not edible.

Their flowers are absolutely incredible. They are very large, yellow-orange and indeed have a waxy feel. Grow with other tropicals like elephant ears (Colocasia and Alocasia), hibiscus, mandevillas, and allamandas.

Banana plants are vulnerable to pests including aphids, mealy bugs, scale and white flies. Avoid root rot issues with good pot and bed drainage.

Success With Succulents

Posted by Hugh on October 6th, 2022

Jade Plant (Crasssula)
Easter cactus

Succulents are beautiful, low maintenance plants that are popular among plant addicts who grow them outdoors and as indoor house plants. Most are indigenous to desert or dryland conditions. They hold water in their fleshy leaves, stems and roots. Overwatering succulent plants is their nemesis. Adequate soil drainage and light are of key importance. These plants are susceptible to root rot when sitting in moist soil too long.

Succulent Plant Collection (most plants are not cold hardy in winter)

Succulents come in a range of colors and shapes. Succulents don’t require much container space they can easily be placed into a small container or plant several in a wide shallow container or a dish garden. Arrange several plants in their own individual pots.

A typical potting mix for house plants and garden containers contains a good mix of coarse sand, perlite and organic materials. A good potting mix for succulent plants contains two-parts coarse sand or perlite, one-part organic material, and one-part garden soil.

When buying succulents, look for plants that show active growth. Avoid plants that are affected by diseases or pests, growth is spindly, or leaves are pale. Succulents love light, and a bright southern window is best for many. Move plants outdoors in spring after threat of frost injury has passed. In the fall, move plants indoors when temps drop into the low 40’s. In the spring, when moving plants outdoors, allow them to adjust to higher light and moderate temperature changes over several days.

Succulents are slow growing plants…so be patient. Use water-soluble house plant fertilizers such as Miracle-Gro®, Espoma®, or Jacks®. Play on the safe side by feeding plants at half the label rate every 4-6 weeks. Fertilize just once in winter as plants are usually resting during the cooler indoor environ. As plants approach spring, transplant most plants into larger pots.

Many succulent house plants are easily propagated by stem and/or leaf cuttings during the spring and summer months.

Popular Succulents (check U.S. hardiness zone for your area)

Indoor: Jade Plants (Crassula spp.), Aloe Plant (Aloe vera), Snake Plant (Sansevieria), Holiday cacti (Schlumbergii spp.), Hen and Chicks (Sempervivum), Crown of thorns (Euphorbia milii), Stonecrop, Assorted Kalanchoes, Aeonium, Ball Cacti.

Outdoor: Hen and Chicks (Sempervivum), Whale’s Tongue (Agave ovatifolia), Stonecrop (Sedum spurium), Echeveria, Pig’s ear (Cotyledon orbiculata).s

Three Standout Pfitzer Junipers

Posted by Hugh on October 6th, 2022

Pfitzer junipers (Juniperus x pfitzeriana) are standouts in the winter landscape (USDA hardiness zones 3-9). Many varieties are utilized as groundcovers. Pfitzers are easy care, low maintenance plants when properly sited in full sun and well drained. Around coastal areas, pfitzers are moderately resistant to salt injury.

Give pfitzers lots of space. Their plume-like evergreen branches spread widely from a central growing point and some corrective pruning may be necessary. From one year to the next, snip back an “offending” or wildly aberrant branch back to preserve its graceful feathery habit and symmetry.

Pfitzer junipers serve as stunning backdrops for low deciduous shrubs and perennials. Small trees ladened with colorful berries such as ‘Winter King’ hawthorn, crabapples, or deciduous hollies to list three) or the colorful bark of ‘Little King’ birch, ‘Sango Kaku’ coral bark Japanese maple, or select cultivars of crape myrtles. They serve as a lush backdrop for low growing evergreen hollies ladened with red or gold berries.

Three cultivars are highly rated:

‘Angelica Blue’ – a horizontal branching form that reaches 6 or 7 feet in height, but their width may be up to 10 feet.

‘Daub’s Frosted’ – a compact, low-spreading, evergreen with its two-toned foliage (blue green foliage frosted with yellow new growth at tips). New growth emerges yellow but matures to blue-green; grows 1-2 feet tall (almost ground-hugging) and 3-6 feet wide.

‘Gold Lace’ – lacy golden plume foliage that reach the center of the plant and intensify in fall and winter; this compact reaches 3 to 4 feet tall and 5 to 6 feet wide.

Scout (inspect) plants for bagworms that may damage the foliage when population numbers are allowed to get out of hand. Bt (Bacillus thuringensis) is a safe organic pesticide when used early in the attack.

Plan ahead. Pfitzer junipers are robust growers, particularly in the mid-South (TN, VA, NC, GA) where shrubs generally grow 20-30% bigger than what is described in most garden books. Around coastal areas, pfitzers are moderately resistant to salt injury. Pfitzer junipers live quite a long time.

Add snipped juniper branches to holiday wreaths, swags or table centerpieces.

Deciduous Hollies Dazzle In Your Winter Landscape

Posted by Hugh on October 1st, 2022

Along I-26 NC Rest Area Planted With Deciduous Hollies

While deciduous hollies (Ilex spp.) are well-known among home gardeners and landscapers, surprisingly few grow them (USDA hardiness zones 3-9 variable by species). In the fall, their branches and twigs are covered in bright red berries. Orange and yellow berried varieties are also available. Birds love them as a winter food source.

Deciduous hollies do not have prickly leaves like evergreen hollies. Their foliage is soft and non-spiny, and are shed by late fall. Two prominent native species — winterberry (Ilex verticillata) and possumhaw (Ilex decidua), plus Japanese winterberry (Ilex serrata) are planted. Numerous hybrid varieties are sold at independent garden centers.

Few gardeners take notice of the tiny greenish-white flowers in spring. Insect pollinators pollinate the blooms. Before purchasing, decide on what cultivars will fit in your landscape site (see below). Cultivars range in size from 2 to 18 feet high and 4 to 10 feet wide. Give individual plants plenty of growing room.

Plant deciduous hollies from spring to early fall in a full to part day sunny site (5+ hours of sun best). Deciduous hollies prefer moist, acidic soils, and don’t mind wet ground. Possumhaw grow tall and wide in moderately alkaline soil. Male clones do not produce fruits, but serve to pollinate female varieties. For optimum berry set, female cultivars should be matched to one or more specific male clones (see below).

Two-year established deciduous hollies are moderately drought tolerant, but produce greater numbers of berries if summer rainfall is adequate. Fertilize in March or April with an acidic organic slow-release fertilizer such as Holly-tone® or Osmocote®. No serious insect or disease problems trouble deciduous hollies.

Clip off berry-covered twigs and branches in fall and winter to bring indoors and arrange in tall vases; no need to add water as cut stems will last quite a while. When shrubs grow too large, cut them back in early spring by one-third or more, even drastically to the ground.

Hedges of deciduous hollies attract all kinds of birds to your property and offer nesting and winter protection for our feathered friends. A background of tall needled evergreens like hemlocks, spruces and pines help make the colorful winter berries to stand out.

Pollinator Info: 6 to 8 feet tall ‘Aurantiaca’ (orange berries), ‘Heavy Berry’, ‘Afterglow’, and compact ‘Red Sprite’ (5 feet tall) are pollinated by early blooming male ‘Jim Dandy’. Late blooming male ‘Southern Gentleman’ pollinates ‘Winter Red’, ‘Winter Gold’, and ‘Sparkleberry’. ‘Apollo’ is a late pollinator for ‘Sparkleberry’ and ‘Winter Red’.

Three Hybrid Oaks Grow Tall And Narrow

Posted by Hugh on September 20th, 2022

Where space is limited, such as along a narrow thoroughfare or snuggled up near a downtown building, here are three (plus two others pictured here) columnar oaks that you can depend upon.

Beacon® is a hybrid swamp white oak (Quercus bicolor) discovered by famed plantsman Dr. Michael Dirr and introduced by J. Frank Schmidt Nursery in Boring OR. It maxes out at 40 feet by 15 feet and makes a strong visual statement. The stout upright branching structure and dense green foliage makes this variety a reliable street tree. It also has an above average yellow fall color. (Zone 4 hardy).

Skinny Genes® is another tight-growing hybrid deciduous oak (English oak Q. robur x White Oak Q. alba). This columnar form is perhaps the narrowest yet. The glossy, very dark green summer foliage is mildew resistant, then leaves turn yellow in autumn. Note…. Beacon is rated more symmetrical and denser branched than Skinny Genes.

Kindred Spirit® is a hybrid cross between Swamp White Oak (Q. bicolor) and Columnar English Oak (Q. robur ‘Fastigiata’). Rising like a sentinel, the tree has a columnar growth habit, growing about 30 feet tall at maturity, with a branch spread of 6 feet. The tree has a low canopy – about 2 feet from the ground. It has attractive large dark green lobed foliage with silver undersides in spring and summer and turns bright red – orange in fall.

All five columnar oaks require some occasional maintenance and pruning upkeep. They tolerate all types of soil that are well-drained. Newly planted trees should be irrigated during very dry periods, particularly during the first two years after planting. Yes, oaks produce acorns which can be messy and attract squirrels to your landscape and sidewalks.

‘Crimson Spire’ oak (*Q. robu*r x *Q. alba)*

Bigroot Cranesbill

Posted by Hugh on September 10th, 2022

*Geranium macrorrhizum* ‘Bevan’s Variety’

Bigroot Cranesbill (Geranium macrorrhizum) is a favorite, easy to grow plant that forms a dense weed-resistant ground cover with attractive foliage and flowers. (USDA zones 4 – 8). This “cranesbill” is a true perennial geranium. It is a rhizomatous semi-evergreen perennial, native to southern Europe, typically grows to 12 inches tall and to 24 inches or more in spread. The rounded grayish-green leaves (4-8 inches long) have 5-7 deeply cut lobes. Leaves are strongly aromatic when crushed. Over the years this slow-growing cranesbill species develops into an attractive vegetative patch that asks for little maintenance.

Three varieties – ‘Ingwersen’s Variety’, ‘Bevan’s Variety’ and ‘Spessart’ – are commonly available at garden centers. ‘Bevan’s Variety’ grows to slightly more than a foot tall and bears magenta-pink flowers that are uniquely veined; ‘Ingwersen’s Variety’ bears pale pink flowers on dark red stems; ‘Spessart’ has white (soft pink) flowers on and off through the summer months. Blooms stand above the foliage, often with some re-blooming in late summer into autumn.

Bigroot cranesbills grow in full sun to partial shade and in average well-drained soil. Plants tolerate full sun in northerly cool areas; otherwise, they tolerate hot humid summers and dry shade better than most other cranesbill species. Plants do not need to be cut back or sheared after flowering. If you demand a tidy look, the taller flowering stems may be mowed back, leaving a rough appearance for maybe 7-10 days. Plants spread in the garden by rhizomes and occasionally self-seed. Clumps may be divided to expand the ground bed faster.

Site this low ground cover at the front of planting borders or edge large urns and planters utilizing this cranesbill and others. Deer and rabbits leave cranesbills alone and the bees work their small saucer-like blooms. Leaves acquire red tones in autumn and stand out more in unseasonably dry weather.

Worst Weed Ever Is Here?

Posted by Hugh on September 2nd, 2022

Mulberryweed (Fatoua villosa) is not related to mulberry trees but its leaves look a little like mulberry foliage. A native of eastern Asia, it was introduced into North America in the latter half of the 20^th century. Currently, it is seen in the Southeastern United States from Maryland to Florida, west to Texas and Oklahoma, north to the Ohio (zones 5-11).

Gardeners may argue whether it’s worse than nutsedge (Cyperus rotundus), creeping Charlie (aka ground ivy), crabgrass, or any other you wish to list. Even the U.S. nursery industry is concerned. It has gotten into growing (potting) media, and growers are warning their customers (garden centers and landscapers) to inspect shipped plants after purchase.

Mulberryweed is an erect, branched summer annual. Leaves are alternate, and roughly triangular in outline with toothed margins. Flowers are borne in feathery clusters in the leaf axils. Flower clusters are purple when young, fading to dark brown with age. Plants flower from late spring through early fall and die after frost.

If you mow over this weed, new growth branches and stays low and grows horizontally. It produces tons of seed and produces multi-generations over the growing season. New seedlings may flower and fruit within 12 days of reaching the 2-leaf growth stage. Learn to pull it out immediately. Individual flowers are inconspicuous, white to cream colored, and are not persistent. Seeds are forcefully expelled at least 4 feet.

Closeup of seed capsule (photos by Jane Conlon)

Seeds germinate from early spring through late fall, resulting in many generations per year. Consequently, although well managed by certain pre-emergence herbicides, populations may continue to build in the absence of aggressive sanitation programs. Herbicide efficacy rankings for this species are based on limited experimental data.

From personal experience, mulberryweed has really become a menace in our landscape. I’ve been sloppy pulling and leaving weeds in place to decompose – a big mistake. I am now carting all weed debris away.

Thanks to Mr. Jason Reeves, Horticulturist at the West TN AgResearch & Education Center in Jackson, TN, for initially identifying mulberryweed.

Salvias – Nature’s Last Hurrah

Posted by Hugh on September 1st, 2022

Salvias are native to central South America. Some species may surprising survive here in Tennessee/Virginia (zone 7) as tender perennials. In the early days of autumn, salvias seem to revitalize – vegetatively and flower numbers. Salvias are both reliable nectar and pollen sources for butterflies and hummingbirds and are seldom damaged by deer. Listed here are four star performers in late summer and autumn.

Blue anise sage (Salvia guaranitica) is a garden annual in northern areas of the U.S. (zone 7b-10). Deep purple flowers are produced from midsummer to fall. The 2-inch long, electric blue, two-lipped, tubular flowers contrast strikingly with the blackish stems. Two cultivars – ‘Black and Blue’ and ‘Black and Bloom’ – may survive a mild winter if plants are well-mulched. Plants develop an open shrubby appearance, to 3-5 feet tall (perennialized) and 2.5 to 3 feet tall (as an annual) in garden beds or large containers.

Mexican Bush Sage (Salvia leucantha) is prized for its dense, arching spikes and ability to produce an attractive late summer bloom of showy flowers (zones 7b-10). The plant feels soft and hairy to the touch, and the bi-color blooms include white corollas and purple calyces.

*S. leucantha* ‘Santa Barbara’ at NC Arboretum in Asheville, NC

Friendship Sage (Salvia x) is a showy violet-purple blooming sage. The cultivar ‘Armsted’ is an annual sage that overwinters in zone 7b.

Fuzzy Bolivian Sage (Salvia oxyphora), aka Bolivian Spearhead Sage, is fairly new in U.S. garden scene, but their bright, hot pink, fuzzy blossoms will surely make them a favorite (zones 8-10). The plant’s deep green tropical-like foliage is glossy green with clear, almost invisible hairs. Flowers appear in late June and plants continue blooming through the October frost, with terminal clusters of hairy rosy-pink tubes. It grows vigorously and can reach 4 feet in height by the end of summer.

**Fuzzy** **Bolivian** **Sage** (*Salvia oxyphora*) at Longwood Gardens

General Care: Plant any of these salvias in the flower garden or in containers in humus-rich, medium moist, well-drained soil and in full sun. Wait until the threat of spring frost has passed. Salvias become moderately drought tolerant 6-8 weeks after planting.

Why My Tree Turns Yellow in Summer

Posted by Hugh on August 27th, 2022

Leaves of some landscape trees turn yellowish- green color in the summer. The common cause for this malady is a lack of minor nutrients (“micronutrients”) that are essential for plant growth. These nutrients are available in the soil in very small quantities. Nutrient deficiencies are not common, except in the high pH soils, particularly the soils the central U.S. south to Texas.

Micronutrients include iron, manganese, zinc, copper, boron, silicon, and molybdenum. These are in contrast to macronutrients (nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), which are required in greater amounts and make up a larger portion of the plant tissue.

A bag of fertilizer (contains N, P, and K) and various forms of lime supply key macronutrients of (Ca) and (Mg). Soil pH plays a role in the availability of minor nutrients, particularly iron (Fe), manganese (Mn), and molybdenum (Mo). Micronutrient deficiencies also may occur when a plant’s root system is compromised, such as by injury, disease, poor site conditions, drought, or water-saturated soils.

Yellowing of the late spring or summer foliage is typically a symptom of a minor nutrient deficiency in specific landscape plants. As examples, look for mid-summer foliar yellowing (called “chlorosis”) on pin oak (Quercus palustris) and river birch (Betula nigra), and manganese deficiency on red and silver maples (Acer spp.).

Deficiency symptoms are marked by pale green or yellow leaves, with veins that remain green. As the deficiency is not corrected, new spring growth is stunted, branches may die back, and the leaf edges (margins) and interveinal areas of leaves may turn brown. In severe cases, the entire tree may decline over several years and die.

Iron deficiency on river birch (*Betula nigra*)

To avoid poor plant health caused by micronutrient deficiencies, test the soil before planting a tree and choose trees and shrubs that are tolerant of the high pH soil conditions. Foliar application of iron is a short-term treatment that can help trees appear more green and healthy in the current season, but must be applied later on when leaves have emerged. Repeated this fertilizer treatment annually.

Micronutrients injected into the trunk of the tree. These treatments help leaves to turn green within a week or two, and can last up to two years. Certified tree arborists can inject “liquid chelated iron” into holes drilled into the trunk of oaks and birch trees. Other products containing ferrous sulfate (iron / sulfur) may be fed directly into the soil around trees and shrubs also improves their foliar color.

Growing Rain Lilies

Posted by Hugh on August 22nd, 2022

Rain lilies (Zephyranthes), aka Zephyr lily, Atamasco lily, fairy lily, et al. are small perennial bulbs that are native to the southeastern United States, Central and South America (USDA hardiness zones 7-10). In the U.S., these bulbous members of the Amaryllis Family (Amaryllidaceae) grow in shady woodlands and wet meadows where they peek out along the edges of a garden.

Rain lilies crave wet to rainy summer weather and perform poorly in droughty soils. Dormant bulbs wake up during periods when rainfall is plentiful in summer and early autumn. Plant (sow) them in the front of the border, in a rock garden, or even in a rain garden. Plantings get more notice by sowing multiples of rain lilies together.

Flower colors range from yellow, white or pink. Butterflies and honeybees are all over these late summer-fall blooming bulbs. Plants have grass-like foliage and their heights range from 2 to 12 inches (5 – 30 cm.) depending on species.

Rain lilies bloom from spring to autumn (species dependent). Sow bulbs at a depth of 3 inches (8 cm), and a spacing of 4-6 inches (10 -15 cm) apart following the last frost of spring. Plant them @ 8-10 bulbs per sq. ft. The top of the bulb should be about an inch under the soil surface and 2-4 inches apart in containers as they look best when crowded and slightly pot-bound.
They multiply rapidly.

Plants grow in partially shaded or sunny parts of the garden that have well-drained, moist, humus-rich, mildly acidic soil. Rain lilies benefit from fertilizing at planting time and annually. In northern gardeners grow these non-hardy bulbs in containers as annuals or overwinter the pots in a cool dry location.

Rain lilies are both pest resistant and critter proof. Bulbs and all parts of the plants contain toxic alkaloids that can cause vomiting, convulsions, and death if ingested.