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

Parrotia: A Great Medium-sized Landscape Tree

Posted by Hugh on February 16th, 2012

Persian ironwood mottled bark

Parrotia (Parrotia persica), aka “Persian ironwood”, is native to Iran, Turkey, and the Caucasus region. Parrotia forms a lovely carefree medium sized lawn or street tree. Tree framework is vase-shaped, initially narrow at the base and flaring out in the canopy as it ages. Mature tree height varies 25-40 feet, depending on location and the seedling or cultivar planted. Rated hardy in USDA hardiness zone 5, parrotia excels in the Southern Appalachian region (USDA zones 6 and 7).

Tiny flowers appear in early March and are rarely noticed along its branches. Clusters of ruby red stamens emerge with no petals. In early spring its witchhazel-like foliage starts out reddish-purple and develop into 3-5 inch long leaves. Summer’s lustrous dark green foliage transitions to a blend of yellow, orange and red colors in autumn. Foliage colors are effective for almost a month.

After 12 – 15 years parrotia’s smooth gray bark begins to exfoliate. In subsequent year, a patchwork of green, white, tan and cinnamon unfolds. Prune away lower branches to better catch the striking mosaic bark.

Parrotia is long-lived with no serious insect or disease issues. A two-year established parrotia resists heat, drought, wind, and urban air pollutants. Seasonal leaf colors are more vivid in full to partial (6 hours minimum) sunlight and on a well-drained acidic soil site.

‘Biltmore’ is most popular cultivar which exhibits tall and upright branching. ‘Pendula’ is a spreading weeping mound form only 10-12 feet wide with branch tips which tend to curve upward.

Within the witchhazel family (Hamamelidaceae), besides parrotia and witchhazel (Hamamelis spp.), are such landscape favorites as sweetgum (Liquidambar spp.), fothergilla (Fothergilla spp.) and loropetalum (Loropetalum chinense).

Re-Potting Indoor Plants

Posted by Hugh on February 13th, 2012

Sansevieria (snake plant) rarely needs re-potting

The golden rule for house plant care is to repot them once a year. Times of seasonal change signal the best opportunity for repotting most house plants. September starts a slowdown and March (late February) a re-awakening period for your house plants. Most, but not all plants, should be re-potted in one of these periods.

Purchase a good “house plant” mix (soil-less media) from a local garden shop. Brand is unimportant, although a really “cheap” mix under $3.00 a bag is suspicious from a quality standpoint. The good mix should contain sphagnum peat moss, composted bark, and perlite (or styrafoam). Some manufacturers add vermiculite for improved moisture retention. Specialty mixes should be purchased for cacti and for orchids.

Re-pot plant(s) into the next larger-sized container (measured as pot diameter). For example, 4 ” plant would be shifted into a 5″ pot or 10″ plant into a 12″ pot. Pot may be clay, ceramic or plastic. It is easiest to maintain all your house plants in one type of pot. You may choose to root and shoot prune to keep the plant in the same container.

Partially fill the new pot with potting media. Pry the plant out of the old pot with a knife or thin screwdriver. Gently remove loose soil around the roots and place in a new pot. Slowly work in the new potting soil around to edges. Loosely fill soil to almost the top of pot lip. Watering soil eliminates air pockets and settles the media around roots. Add additional soil as needed.

Finally, do not save unused potting soil more than six months. The “wetting agent” additive has lost its activity. Dispose of the soil in a garden bed and purchase a fresh potting mix.

General Tree/Shrub Fertilizer Recommendations

Posted by Hugh on February 9th, 2012

Fertilizer Aisle at Garden Center

Fertilize most landscape shrubs and trees in winter or early spring with a granular 10-10-10 at a rate of 20 lbs. per 1,000 square feet when the ground cover is dry. A 19-19-19 fertilizer is distributed at 10 lbs per 1000 square feet. Distribute within an area 3 feet out from the trunk or shrub crown and 5 feet beyond the end of the branches. Most of us don’t care to haul a 20 or 40 lb bag of fertilizer from one tree to the next. A one pound coffee tin holds about 2 pounds of fertilizer.

Encapsulated slow release fertilizers deliver the nutrients soil temperatures are warm. Each capsule, called a “prill”, is soil moisture and temperature sensitive. The prill meters out a precise amount of the 3 key nutrients (nitrogen, phosphorus and potassium) over a 3, 5 or 9 month time period. In the warmest areas of the U.S., slow-release fertilizers deliver in a shorter time period. Prolonged drought periods also interrupt prill release. Overwatering meters out fertilizer faster and plants often appear nutrient-starved by late summer.

Water soluble fertilizers such as Miracle-Gro™, Miracid™, Jacks®, Peters®, or Hollytone® are great alternatives. These fertilizers are effective for 4-5 weeks and are usually applied bi-monthly from late March thru mid-August on a 6-8 week schedule.

In most areas spring rainfall is adequate to water the fertilizer in and leach it down to the tree/shrub root zone. Otherwise, you should irrigate to carry down whatever product you’ve applied.

Keep in mind that these are general recommendations and some plant exceptions apply.

‘Quasimodo’ Vernal Witchhazel

Posted by Hugh on February 7th, 2012

#3 Container of 'Quasimodo' Vernal Witchhazel (photo by Alex Neubauer, Belvidere, TN)

Vernal witchhazel (H. vernalis) is a dense growing 8-12 foot native shrub which blooms in mid-winter in the Southern Appalachian region (USDA zones 6 and 7). It is winter hardy to zone 4.

Small ½ inch wide yellow to red flowers, flushed red at the base, emit a pleasant witchhazel aroma in February. Often, it is the fragrance which has passerbys taking notice of the small strap-like red flowers blooming in the middle of winter.

New leaves start off with a reddish purple tint in early spring. The 2 – 5 inch long by 2 – 3 inch wide leaves are medium green and remain pest free from spring thru autumn. Fall leaf colors transition from green to yellow to gold. Dead leaves often stick on throughout the winter, concealing large percentage of the flowers. The root system possesses a strong suckering habit. The branch wood displays a pale gray color.

‘Quasimodo’ is a compact 3 – 4 foot high shrub, slightly taller than wide. This diminutive cultivar is excellent choice for a small garden. Quasimodo was hybridized and introduced by Pieter Zwijnenburg in the Netherlands. Its burnt orange flower color stands out better in the mid-winter landscape. Bloom season lasts 3-4 weeks. Quasimodo drops its leaves in the fall so that all flowers are in plain sight.

Vernal witchhazel grows in full sun to moderate shade and requires little extra care. The soil should be adequately drained and mildly acidic.

Key Points Whether To Grow Peaches

Posted by Hugh on February 6th, 2012

Select The Best Peaches for Your Region

Peaches grow in other places besides Georgia, USA. A decade long period of mild winters in the Southern Appalachian region (USDA zones 6 and 7) have increased gardener confidence about growing peaches. Peaches (Prunus persica) tend to flower in early spring when the threat of spring frosts is still high. In many years spring frost may kill 80% of flower buds, yet still produce a “full” crop in July and August.

Standard (non-dwarf) peach trees grow and are easy to harvest by pruning them to 10-12 feet in height. Dwarf peach trees are unreliable as they live only a short time and are not worth the high purchase price. Dwarf peach root systems are weak and break off from the graft union.

Only freestone peach varieties are listed below. If you garden in zone 7-a or further north, their long winter chilling requirement is not a problem. Freestone peaches are great for eating and ideal for baking and canning; the flesh does not stick to the pits. Clingstone peaches are also a good choice for their sweetness and taste.

Table 1. New peach varieties and approximate harvest times for East Tennessee, Western NC and Southwest VA (zone 6-b):

3^rd week July Contender (yellow flesh, freestone)

4^th week July Nectar (white flesh, freestone)

1^st week August Carolina Gold (yellow flesh, freestone)

2^nd week August China Pearl (white flesh, freestone)

Late August Intrepid (yellow flesh, freestone)

Table 2. Older reliable varieties for East Tennessee and Southwest Virginia include:

Cresthaven (medium to large fruit, yellow flesh, freestone)

Jefferson (early season, medium yellow-orange flesh, freestone)

Monroe (late harvest, medium yellow flesh, freestone)

Red Haven (medium, nearly fuzzless, yellow flesh, freestone)

Credit: Dr. David Lockwood, Extension Fruit Specialist at the Universities of Tennessee and Georgia recommend these varieties.

Tree and Berry Fruit Pollination Chart

Posted by Hugh on February 3rd, 2012

Apples Are Self Unfruitful, Cross-pollinator Required

A frequent question of newbie fruit gardeners is what will pollinate what. Do I need many varieties or can all be the same variety? The four common terms are used:

Self-pollinated: transfer of pollen occurs within the same variety.

Cross-pollinated: transfer of pollen occurs between two varieties.

Self-unfruitful: low fruit set unless the blossoms are fertilized with pollen of another variety.

Self-fruitful: varieties that set fruit with their own pollen.

Apple: self-unfruitful with two or more varieties required for good cross-pollination. Some varieties are poor pollen providers (‘Winesap’, ‘Jonagold’, ‘Mutsu’ are examples) and a third variety is required.

Pear: mostly self-unfruitful with two or more varieties required for good cross-pollination. Asian pears do not pollinate European pear varieties.

Plum: Japanese plum, represented by varieties ‘Burbank’, ‘Shiro’, ‘Santa Rosa’, and ‘Methley’, are self-unfruitful. European varieties do not pollinate Japanese varieties.

European plum, represented by ‘Stanley’ and ‘Damson’, are self-fruitful and pollinate other European varieties. All other European plums require pollen from another variety.

Sour (Tart) Cherry: self-fruitful; recommend ‘Montmorency’, ‘Early Richmond’, ‘Meteor’

Sweet Cherry: self-unfruitful, cross pollination required; recommend ‘Hedelfinger’, ‘Ranier’, ‘Viva’, ‘Valera’, ‘Venus’, ‘Hardy Giant’. The variety ‘Stella’ is self fruitful.

Peaches: self-fruitful, but heavier yields when two or more varieties are planted.

Strawberries – self-fruitful

Blackberries – self-fruitful

Raspberries – self-fruitful

Grapes – American bunch, French hybrids, V. vinifera types – self-fruitful

Grapes – Muscadine – self-unfruitful, cross pollination required

Blueberry – self-unfruitful, cross pollination required

Hardy kiwi – self-unfruitful, cross pollination required

Gooseberry, Currant – self fruitful

Elderberry – self-unfruitful, cross pollination required

Formerly A Tree… Now A Hat Rack

Posted by Hugh on February 1st, 2012

Former Maple Tree after Bad Pruning

Tree topping continues! The concern about a large tree falling on the house, garage, autos or pedestrians sends out calls to cut the tree back. If the tree in photo does recover (grow), the new branches will be mostly weak suckers. After 2-3 years, the sucker growth will be susceptible to high winds and snow/ice storms than if the original tree had been left alone or pruned correctly.

The proper pruning job does cost more money than a “butcher job” in photo. This is because the tree pruner is more highly skilled. The shade tree will enjoy a longer life and keep your summer air conditioning bills lower. Also, average people do

Leading reasons why homeowners butcher their trees:

1. My neighbor did it first

2. Tree was blocking signage to my business

3. Didn’t know that it was the wrong practice

4. Unlicensed tree pruner said it was the right thing to do.

To avoid this problem, select small to medium sized maturing trees such as redbuds, dogwoods, crabapples, hawthorns, Japanese maples, trident maple, and lacebark elm.

Leyland Cypress Too Big For Many Sites

Posted by Hugh on January 30th, 2012

Young Leyland Cypress TOO Close to Townhouse -photo by Ken Soergel

Leyland cypress (x Cupressocyparis leylandii) grows into a 50 foot tall evergreen behemoth. What happens when the plants (in photo) get too close to the small deck(s)? Access to the deck from the stairs will become impossible as the evergreens swallow up the entire back yard. Looking out from the deck and windows from the home won’t be likely within 5 years.

Here are six better low growing evergreen alternatives in the 12-25 foot height range which should be better fit into this landscape are:

Leatherleaf viburnum (Viburnum rhytidophyllum) @12-15 feet in 15 years

Prague viburnum (Viburnum x pragense) @8-12 feet

Skip laurel (Prunus laurocerasus ‘Schipkaensis’) @8-12 feet

Emerald arborvitae (Thuja occidentalis ‘Smaragd’) @18-20 feet

Foster No. 2 holly (Ilex x attenuata ‘Foster No. 2’) @16-18 feet

Nellie R. Stevens holly (Ilex x cornuta ‘Nellie R. Stevens’) @18-20 feet

Another option is a plant a hedge row of evergreens such as hemlock (Tsuga canadensis), white pine (Pinus strobus), or upright junipers (Juniperus chinensis). Evergreens would require pruning at least once a year.

In the Southern Appalachian region (USDA hardiness zones 6 and 7), Leyland cypress is not a good choice for an average size residential lot. Limit plantings to public parks, golf courses and large commercial properties and space at least 16 feet apart for good air movement around plants.

Leyland cypress is susceptible to three serious foliar diseases of which there are no fungicidal curative measures.

Dawn Redwood Lives On From Its Prehistoric Past

Posted by Hugh on January 26th, 2012

Fall Leaf Color of Metasequoia 'Ogon'

Dawn redwood (Metasequoia glyptostroboides) was thought to be extinct for the past 20 million years. Since 1948 gardeners have witnessed its re-introduction back into the North American landscape from Sichuan-Hubei Provinces in China where the tree was re-discovered.

Dawn redwood prefers a well-drained, compost-rich, acidic soil. This deciduous conifer tolerates standing water for a brief 2-3 day span, not as long as bald cypress (Taxodium spp.). If the tree is left branched to the ground on an open site, the trunk often develops large, contorted “boles”.

Active spring/summer growth emerges bright green and the fine textured foliage quickly darkens up to medium green. Autumn foliage turns a tan to pinkish color, finishing reddish bronze before dropping.

The main trunk displays “arm pits”, depressed areas along the main trunk where the branches are attached. The trunk base flairs out at the surface of the ground. During the winter the tree’s leafless framework is easily identified by its straight butressed trunk, strong central leader and wide horizontal conical branching. Its shredded reddish brown bark is an added winter attribute.

Dawn redwood is rarely bothered by disease and pest problems. Spider mites may be problematic during long dry spells. Japanese beetles may consume some foliage, but the tree’s fast growth rate cosmetically repairs most of the damage incurred. Ultimately, dawn redwood grows to 80-100 feet tall and is best sited for large properties such as public parks, golf courses, and college campuses.

Gold Rush® (‘Ogon’) dawn redwood is a popular gold-leafed form. It grows slightly slower than the species, but eventually attains large tree status.

Soil Testing Is Fool-Proof Garden Insurance

Posted by Hugh on January 18th, 2012

Gardens start with great soil!

Soil testing is a gardener’s best low cost insurance for enjoying a gorgeous garden or lawn. A soil analysis may be a problem solver, informing you of the soil nutrient content and pH. It accurately calculates how much chemical fertilizer, limestone, manure and other components to add. You save money is your soil is already rich enough or too high in certain nutrients, lime or sulfur.

The pH is a measure of how acidic (below 7.0) or alkaline (above pH 7.0) the garden soil may be. Acid-loving plants such as azaleas, rhododendrons, dwarf conifers and blueberries prefer soil pH below 6.0. An alkaline pH benefits growing some dianthus, ferns and lenten roses. Also, some soil nutrients are less available to plants above pH 7.0.

Soil test early, at least once every 4-5 years. Separately test lawn, vegetable, fruit, and flower garden areas. If you grow a large number of roses, test this area separately.

Randomly sample 4-5 areas of each separate garden bed. The soil should be aired dry for several days and collect enough to fill a large 5 oz. baby food jar.

The local Extension office or full service garden center now in mid-winter before the rush of spring gardeners begin tilling. The cost is very modest, usually $8-12 per sample in most states.