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

Peace Lily And Anthurium Plants Around Home Or Office

Posted by Hugh on February 8th, 2016

Peace lily (Spathiphyllum)

Red Spathe Anthurium

Peace Lily (Spathiphyllum) and anthurium are near perfect foliage plants in poorly lit areas around your home or office. They’re native to the tropical rainforests of Central and South America. Both plants are shade-lovers in their native habitats. Direct sunlight for more than one hour will likely burn leaves. They’re members of the aroid (Araceae) family, as are many tropical foliage species.

Leaves are glossy, pointed, and oval or arrowhead-shaped. Their spathe-like flowers are unique and beautiful. White (peace lily) or red (anthurium) flowers emerge from the leaf stalk that gradually fade to green or yellow over many weeks.

Peace lily and anthurium are comfortable at temperatures between 60 – 85 °F. In spring and summer, plant(s) can be moved outdoors provided temperature is above 60 °F. Both thrive in high humidity. Locate near a room humidifier during the dry winter months. Another alternative is to set pots on a tray filled with moist pea gravel and spray plants once or twice daily. Never set a pot directly in water or keep soil (potting media) constantly we as this will promote root rot.

Both species prefer a moist well-drained soil and should be watered weekly with room temperature water. Allow tap water, usually from city fluorinated sources, to stand and dissipate away fluorine or chlorine gas over a 24 hour period before watering. Fertilize monthly during the spring, summer and fall with a water-soluble fertilizer such as Schultz®, Miracle-Gro®, Daniels® or Jacks®. Mix at only one-half the label rate.

Repot plants annually. Remove from pot and divide clumps with a sharp knife. Carefully cut apart plant divisions to include healthy roots and leaves. Clip off spent flowers and old leaves. Pot into a sterile well-drained potting soil.

Monthly inspect the underside of leaves for mites or mealybugs. Problem pests are usually found on the underside of leaves where they’re feeding. Prune off heavily infested leaves and spray insecticidal soap to be rid of insects.

Growing Orchids Is A Great Hobby

Posted by Hugh on February 6th, 2016

Lady Slipper Orchid (Paphiopedilum)

Phalaenopsis orchid at Biltmore Estate in Asheville, NC

At one time growing orchids was an elitist hobby for the very rich in our society. Orchids were expensive to purchase. Today, local greenhouses and garden centers sell orchids at affordable prices. Moth (Phalaenopsis) and lady slipper orchids (Paphiopedilum) are the simplest to grow. Here are some easy tips to make home orchid growing a rewarding year-round hobby.

Many orchid species are difficult to grow inside modern homes; not so for the moth and lady slipper orchids. In their natural habitat, orchids are plant epiphytes which grow on tree trunks and branches in the humid tropics. Their thick fleshy roots draw moisture from the air and various surfaces around the roots.

Most important, in northern temperate regions, orchids may spend most of the spring and summer months outdoors beneath the dense leafy canopy of a shade tree in your landscape. In early fall before cold night temperatures arrive (below 40 ºF), plants come back indoors. Orchids are comfortable in home temperatures between 60 and 80 °F.

Low room humidity between 10-40 % during the winter may challenge orchids. Bathrooms and the kitchen are the most humid rooms in a typical home. Group several plants together and set on a tray filled with moist pea gravel. Spray or mist plants daily in winter.

Across the Northern hemisphere outdoor light peering through windows in the winter months is generally lacking. Sunlight intensity is weak and day length is short between November through February. Moth and ladyslipper orchids need only bright light and not direct sunlight.

Orchids should be planted in special potting mix containing coarse bark, sphagnum peat moss and perlite. Some medias add charcoal to improve drainage and filter out impurities. A good orchid potting mix retains moisture only a few days. Otherwise, the fleshy orchid roots begin to rot if growing media stays too wet over many days. Never leave an orchid standing in water over many hours. Annually, repot your orchids after flowering, usually in the spring or in late summer.

Fertilize orchids “weakly” and “weekly” from spring thru fall with a high phosphorus-based soluble house plant fertilizer. Package directions for most house plant fertilizers are too strong for orchids. Use only half the recommended rate and feed weekly. Orchids are fertilized once monthly from December thru February. After repotting, do not fertilize for 2-3 weeks.

Coleus Thrive In Summer Heat And Humidity

Posted by Hugh on February 1st, 2016

Coleus ‘Campfire’ on Ohio State Campus

Coleus flowering in October

Coleus (Plectranthus scutellariodes) is a summer annual treasured for its colorful foliage. Plants thrive in summer’s heat and humidity (USDA hardiness zone 11). Coleus is a member of the nettle family Lamiaceae. You can create dazzling beds of color using coleus alone or mixed with flowering annuals.

Modern day coleus grow more compact and better branched. Trailing forms add another option. Every year new varieties surpass previous color barriers. The color array includes green, pink, yellow, orange, red, purple (almost black), cream, and white. Choose from solids, blended colors, or color-veined foliage.

Most varieties perform best in morning sun and afternoon shade, although shade only types are available. Cultivar series such as the ColorBlaze®, Wizard Sun®, Main Street®, and Ducksfoot® prefer partial to full sun, while the Mosaic® and Kong® series excel in moderate shade. ‘Fish Net Stockings’ struts lime green leaves with dark purple venation.

In northern climes (zones 7 and north), coleus prefers moist, compost-rich soil. Excesses or deficits in soil moisture should be avoided. Plant coleus after the spring frost threat has passed and soil temperatures have warmed above 50 ºF. Light feeding with a water soluble fertilizer such as Miracle-Gro™, Peters™, or Schultz™ every 6 -8 weeks is recommended. For containers incorporate a slow release fertilizer or feed with water soluble fertilizer.

Spacing between plants differs with cultivar size and vigor and this information is usually printed on the plant tag. In general midsize and trailing cultivars should be 16-18 inches apart. Large shade types cultivars should be spaced 24 inches apart unless they’re routinely pinched back.

Over the first 4-5 weeks newly set plants benefit by pinching (light tip pruning) to increase branching and plant density. New coleus cuttings may be quickly rooted from pinched shoots. After 3-4 weeks you can plant rooted cuttings into new garden areas.

Many gardeners opt to pinch off the small flowers to channel energy into plant growth and enhance leaf color and size. Some new cultivars exhibit delayed flower formation.

Scale, spider mites, mealybugs, whiteflies and aphids are occasional pests on coleus.

Coleus MainStreet ‘River Walk’

List Of Dioecious Trees And Shrubs

Posted by Hugh on January 29th, 2016

Kentucky coffeetree (Gymnocladus diocus)

Ginkgo or Maidenhair tree (Ginkgo biloba)

Some tree species are dioecious, that is produce single sex flowers (either male and female). Male flowers produce pollen and no fruits. Female flowers bear seeds or fruits. You may purchase male clones to avoid picking up messy seed pods or capsules in the fall. If you are allergic to certain tree pollens, avoid planting dioecious male trees.

Most popular of dioecious landscape shrubs are the hollies (Ilex spp.). In holly world many cultivars (varieties) seem to be specially “married” to one another. Gardeners may select female plants for their colorful fruits in fall and winter. Holly fruits may be red, yellow or white colored depending on the cultivar. Be certain that the correct pollinating variety has been planted nearby the specific female cultivar(s). For example, the male clone ‘Apollo’ will pollinate primarily ‘Sparkleberry’ female hollies.

Over the years male clones of several landscape trees have come to dominate our yards and gardens. Male fruitless types do not litter the ground with messy pulpy fruits and seed pods. Ginkgo is one such example. Female ginkgoes produce foul smelling apricot looking fruits. When the ripened fruits fall on sidewalks, the area around them reeks a horrible odor. Male ginkgoes produce no fruits and male clones are grafted by nurseries.

You may run into a third, slightly confusing group are “Polygamo-dioecious” species. This means the male and female flowers grow on separate trees, but occasionally produce perfect flowers on each tree as well. Best examples are certain species and varieties of Maples (Acer spp.), Honeylocust (Gleditsia triacanthos) and Spicebush (Lindera benzoin). These maple types produce few or no fruits in most years.

List of Dioecious Species:

Certain maples -example: boxelder maple (Acer negundo)

Tree of Heaven (Ailanthus altissima)

Japanese aucuba (Aucuba japonica)

Bittersweet (Celastrus scandens)

Plum yew (Cephalotaxus harringtonia)

Katsura tree (Cercidiphyllum japonicum)

Fringetree (Chionanthus spp.)

Smoke tree (Cotinus coggygria)

Persimmon (Diospyros virginiana)

Hardy Rubber Tree (Eucommia ulmoides)

Ash tree (Fraxinus spp.)

Ginkgo, maidenhair tree (Ginkgo biloba)

Honeylocust (Gleditsia triacanthos)

Holly (Ilex spp.)

Juniper (Juniperus spp.)

Spicebush (Lindera benzoin)

Osage orange (Maclura pomifera)

Mulberry (Morus spp.)

Bayberry (Myrica pennsylvania)

Amur Cork Tree (Phellodendron amurense)

Podocarpus (Podocarpus macrophyllus)

Poplar or Aspen (Populus spp.)

Willow (Salix spp.)

Yew (Taxus spp.)

Stinking Cedar (Torreya taxifolia)

Consumer Gardening Trends For 2016*

Posted by Hugh on January 26th, 2016

Leisure Time By Pool

Awareness of Beneficial Insects In Landscape

The Garden Media Group (GMG) has released its annual Garden Trends Report for 2016. The report, titled “Syncing With Nature,” identifies eight consumer trends that the group predicts will shake up the garden and outdoor living industry this coming year.

The report finds “gardening” has transformed into a connected lifestyle in 2016, with a rising millennial generation becoming more involved. The eight new trends show ways the gardening and outdoor living industries can connect not only with traditional gardeners but with a broader community.

GMG reports that “consumers are seeking to enhance their health and wellbeing and support their busy lifestyles. They’re merging technology with nature to explore, educate and entertain. More people have a passion for preserving the earth, and bring their home landscapes in sync. They desire a sustainable lifestyle and an eco-friendly garden and outdoor space.”

Connected Greenery – Garden centers and shoppes should embrace technology, syncing garden habits with technology. New gardening apps demonstrate how to grow indoor and garden plants on Instagram or on YouTube.
Combine Tech with Nature – People want to engage kids with gardening, health and fitness in fun new ways. Whether running, playing or storytelling, this trend has the potential to mobilize a new generation of nature lovers, while getting them outside to play.
Gardening That Combines Nature’s Beauty, Health And Wellness – People are adopting concepts like “edible landscaping” of fresh antioxidant edible berries and easy care landscape plants.
DIY Lifestyle – is shifting from “doing” to “making.” Property owners and renters alike want to experience outdoor living in a more hands-on way. Hot trends include providing materials for beer and wine making.
Outdoor living enhanced – includes evening lighting, porch swings, swimming pools, and designs of whimsy.
Landscape Becomes Multi-layered – addition of trees, shrubs, flowers, vines, grasses, and ground covers that provide food and habitat that are beneficial to wildlife, birds, and insects; choose plants of various shapes and sizes such as dwarf conifers, climbing vines on trellises.
Petscaping – pet owners spend about $60 billion on their pets. Switch to safe organic lawn products and limit use of harmful garden chemicals.
Protect and Conserve Earth’s Resources – gardening with less water such as cacti and succulents and to protect and conserve resources with small lifestyle changes.

*Source: Garden Media Group, Kennett Square, PA. Check their website for a full report.

Petunias For Nearly Every Garden

Posted by Hugh on January 21st, 2016

Petunia x ‘Easy Wave Pink Passion’

‘Supertunia Raspberry Blast’

Petunias (Petunia x hybrida) are top performing summer flowering annuals. There are hundreds of colorful varieties to beautify any flower bed or container garden.

Petunias are divided into three basic types:

Grandiflora petunias grow 8-12 inches tall and 8-10 inches spread; they start out upright branched and bear large size 4 to 5 inch wide blooms. Ideal for flower beds, window boxes, and other containers. By mid- summer vegetation and flowers spill over the sides of containers.
Floribunda (or Multiflora) petunias grow 8-12 inches tall and 8-10 inch spread; produce smaller, more abundant flowers that withstand harsh weather conditions. They’re much more versatile and can be planted in areas not suitable for Grandifloras.
Spreading petunias grow 8-10 inches tall and 2-3 feet spread; they trail along garden beds as a non-stop blooming ground cover or spill over edges of containers.

Hundreds of cultivar series are available starting with Waves®, Cascadias®, Supertunias®, Madness®, and Sulfinias® to list just a few. Double and single blooms offer a selection of solid and multi-colored flowers.

Petunias ask for weekly watering and full day sunlight (best) to achieve maximum blooming potential. They will grow in partially shaded locations but bloom less and plants tend to stretch. Petunias are heavy feeders. Before planting petunias work lots of compost into the soil and broadcast a slow release fertilizer over the entire bed. By mid-summer, plants, particularly those in containers, may become nitrogen deficient. Bottom leaves are first to turn yellow and plants bloom more sparsely. Feed container plants with a water soluble fertilizer such as Miracle-Gro®, Peters®, or Schultz® weekly or twice monthly at label rates.

When purchasing plants at garden center, select those with compact habit and unopened buds. Deadhead petunias, e.g. remove flowers to prevent or eliminate seed heads. In mid-season (late July, set your lawn mower to highest setting (5 inches recommended) and mow over taller varieties. Fertilize with 10-10-10 or equivalent product and irrigate. This will re-invigorate the petunia bed to bloom into mid- to late-fall.

Petunias are disease and pest resistant. Do not plant petunias in the same garden area more than three consecutive years to prevent buildup of soil -borne diseases.

Soil pH- What’s It All About

Posted by Hugh on January 18th, 2016

Rhododendron

Azaleas at Callaway Gardens

Soil pH is an indicator of the relative abundance of hydrogen (H⁺) ions and hydroxyl (OHˉ) ions in garden soils (Table 1). These ions play a very important part of soil fertility and a plant’s ability to absorb nutrients from the soil. The pH scale runs from 1 (highest acidity) to 14 (highest alkalinity). Soil pH of 7 is neutral.

Fourteen (14) of seventeen(17) essential plant nutrients are obtained from the soil. Most nutrients that plants need are readily available when the pH of the soil solutions ranges from 6.0 to 7.5, or slightly acid to neutral. Phosphorus is a major plant element that becomes less available below pH 6.0 and above 7.0.

Plants drink (absorb) nutrients that are dissolved in the soil water. Some minerals are more soluble in the company of H⁺ ions, and other minerals are more soluble in the company of OHˉ ions. Acid soils hold more H⁺ ions, and iron, manganese and phosphorus are more soluble in these soils. Alkaline soils have more OHˉ and calcium, magnesium, potassium, and molybdenum are more soluble in these soils.

Table 1: pH range and Nutrient Availability

Acidic Soil (below 7) Neutral = 7 Alkaline Soil (above 7)

More H⁺ Distilled (Pure) Water More OHˉ

Key Nutrients Most Available below pH 6: Key Nutrients Most Available above pH 7:

Iron Calcium

Manganese Magnesium

Aluminum Potassium

Molybdenum

Most (not all) nutrient elements are available between pH 6.0 to 7.0. As soil pH changes up or down, some elements becomes more soluble and available to the plant. Extremes in soil pH range, below 4.5 or above 7.7, may contain toxic nutrient levels and injure plant roots.

Certain plants have specific nutritional needs. Acid-loving plants (in the Ericaceous family) such as rhododendrons, azaleas, and blueberries are some examples. These plants don’t “love” acidic soil, but absorb higher amounts of iron compared to other plants. Ericaceous plants can not find enough soluble iron in neutral or alkaline soils where it is scarcer. They are also very efficient in absorbing phosphorus at a lower acidic pH.

Watering Tips When Away On Vacation

Posted by Hugh on January 15th, 2016

Potted Caladium and Heucheras Need Watering

Backup Watering System

Summer annuals: Hot July – August weather may demand daily or twice-daily watering for container-grown annuals. A trustworthy neighbor may have to handle these chores.

Flowers and vegetables: When there is no rain within a week, water deeply any vegetables that are bearing fruits like tomato, peppers, and squash. Plants will keep producing far into fall if supplied adequate moisture during late-summer dry spells.

Bulbs: Caladiums, cannas, elephant ears, dahlias, and others require deep weekly watering. Lilies, gladiolas, blackberry lilies, crocosmia, pineapple lilies (Eucomis), and others do not need watering.

Lawns: Cool-season grasses such as bluegrass, perennial ryegrass, and tall and red fescues will naturally go dormant. Warm season grasses like burmuda and zoysia tough it out over dry hot spells. Leaf blades turn brown, but green back up when rainfall returns. If you routinely irrigate your lawn during the summer, cutting off water may be devastating. Keep cool season grasses mowed tall, at least 3 inches or more.

Perennials: Most established perennials and ornamental grasses commonly survive moderate dry spells. Most newly planted perennials, planted 6 weeks or more and mulched, should be okay. Water perennials and grasses deeply before leaving on your trip. Shallow rooted ground covers like ferns, astilbes, and some sedges (Carex) should be irrigated by a trustworthy neighbor.

Roses: supply one inch of water per week, either from rainfall or supplied by you. Drip irrigation or soaker hoses irrigate roses without wetting foliage which can trigger disease outbreaks.

Trees and Shrubs: Some species are more drought-tolerant than others. Deeply water newly planted additions before leaving on trip; maintain 2-3 inch mulch layer around the base of young trees and shrubs to hold over trees 2-3 weeks without natural rainfall.

Houseplants: are best left in the hands of a neighbor. Otherwise, repot plants into larger containers. Small pots require more frequent watering. For extended stays away for home, first water plants thoroughly; fill bathtub with a shallow amount of water (to increase humidity). Do not set the base of pots in water. Keep room temperatures cool and reduce direct sunlight.

Tree Diversity Important In Urban Parks And Streets

Posted by Hugh on January 12th, 2016

Blue ash (Fraxinus quadrangulata) at East TN State University Arboretum in Johnson City, TN

Young Princeton elm (Ulmus Americana)

In recent years urban tree diversity has become a buzz topic. The threat of losing entire street plantings to a deadly exotic disease or pest has to often become the reality. Nearly a century ago, urban tree-lined thoroughfares were laid bare by losses of American elms (Ulmus americana) and chestnuts (Castanea dentata) to Dutch elm and chestnut blight diseases respectively.

Thousand cankers disease (TCD) is a disease complex currently threatening millions of black walnut (Juglans nigra) trees in forests and urban areas. TCD is the result of the combined activity of a fungus and walnut twig beetle.

Asian long-horned beetle continues to kill tree populations in several Mid-Atlantic and Midwest states. It is an invasive wood-boring insect that attacks hardwood trees, including maple (Acer spp.), birch (Betula spp.), beech (Fagus spp.), poplar (Populus spp.), and elm (Ulmus spp.).

Emerald ash borer is destroying native and European ash (Fraxinus spp.) across the U.S. and around the world. Oak wilt disease is laying ruin to oaks (primarily the “black oak” species) in several states.

Norway maple has been widely used on residential streets because it is a long -lived attractive tree, and holds up to soil compaction and air pollution. Unfortunately, this non-native maple is weedy, producing abundant seeds which invade native woodlands and aggressively compete with native plants.

Tree scientists are keen about Shantung or Purpleblow maple (Acer truncatum). It has an attractive appearance, but does not propagate well (USDA hardiness zones 4 – 8). This Asian maple species grows 25 – 30 feet tall and wide, is exceptionally heat and drought tolerant, and adapts to either full sun or moderate shade. Hybrid cultivars like Norwegian Sunset® and Pacific Sunset® exhibit exceptional heat and drought tolerance, good disease and pest resistance, and boasts bright red fall leaf color.

‘Norwegian Sunset’ maple (photo from J. Frank Schmidt Nursery)

Three Easy Care Foliage Plants For Your Home

Posted by Hugh on January 9th, 2016

Dumbcane (Dieffenbachia)

Calthea for sale at a garden center

Chinese Evergreen (Aglaonema), Dumbcane (Dieffenbachia), and Calthea (Calthea spp.) are three similar looking tropical house plants (USDA hardiness zones 8 through 11). Likely, you have seen these easy to grow foliage plants inside restaurants, shopping malls, offices, and at the public library.

They grow in medium to low light areas of the home or work place where many flowering plants will not thrive. They dislike room temperatures below 55 °F and a dry atmosphere. Browning leaf edges may be a symptom that room air is too dry. Turn plants every few weeks for furnish adequate light to all sides of the plant.

Spring-summer-fall fertilizing should be every 2 weeks with a water soluble “house plant fertilizer” at one-half package directions. Winter feeding is usually unnecessary. Irrigate with room temperature non-fluoridated water to avoid burning the foliage.

Plants may be moved outdoors in summer and placed under a large shade tree to receive filtered or indirect light only.

Always water plants thoroughly and do not leave them sitting in standing water for long periods. Plants should be repotted annually, usually in early fall or in late winter. Snip off older bottom leaves that have withered and died.

Diseases rarely bother all three foliage plants. Occasional pests are aphids, mealy bugs, spider mites and scales that may curl, speckle and bronze leaves. Inspect the leaf underside for webbing and spray with insecticidal soap or neem oil. Respray every one to two weeks until pest has been managed.

Chinese evergreen (Aglaonema) has a decorative patterned foliage and available in many varieties.

Dumbcane (Dieffenbachia spp.) reach heights of 4 to 6 feet; related to Aglaonema, Spathiphyllum and Philodendron.

Calthea (Calthea spp.) available in many varieties with colorful foliage and flowers in plant family Maranthaceae.

Caution: Foliage of Chinese evergreen and dumbcane are toxic and should not be ingested. If chewed or eaten, it can cause temporary swelling of the tongue and throat, leading to a temporary loss of speech and sometimes may result in suffocation. Keep plants away from children or pets. Calthea leaves are not toxic.