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

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.

Don’t Crawl /Let’em Weep White Pine

Posted by Hugh on January 15th, 2012

4-foot Young Weeping White Pine

Pinus strobus 'Pendula'

In the beginning was a small weeping pine which wanted to crawl along the ground because it had no “legs”. The gardener came along and straightened up the leader and attached it to a tall pole. Straightening and staking continued for several years. Many years later it grew into a tall weeping white pine (Pinus strobus ‘Pendula’).

The leader and branch shoots pf white pine emerge in late April. The 3 – 5 inch long needles have fully elongated by early June in the Southern Appalachian region (USDA zones 6 and 7). Staking is best performed anytime from mid to late June. The shoots become semi-woody, yet are still flexible.

The main shoot (leader) is bent vertically upward and tied to the stake. The staking and tying procedure is neither complicated nor time consuming. Use soft jute or cotton twine, and not wire twist-ems® or plastic ties for fastening to the stake or a trellis. After 6-8 months, loosen the ties so they won’t girdle the tender main shoot (leader).

At planting position a sturdy 12-16 foot metal or heavy duty plastic stake close to the trunk. White pine grows 12-18 inches per year. On rare occasions a tree may produce multiple leaders. Remove all but the one you want to continue up the stake. Within 8-10 years, your weeping white pine should support itself on its strong straight leader and the stake may be permanently removed.

‘Little King’ Birch For Small Gardens

Posted by Hugh on January 12th, 2012

'Little King' River Birch at Daniel Stowe Bot. Garden in NC

Little King, aka Fox Valley™, (Betula nigra ‘Little King’) is a 10-12 foot tall shrubby river birch, which fits into small landscapes. Simple minimal pruning can shape it into a lovely small tree. Little King possesses the desirable traits of large river birches, including an oft-white exfoliating bark.

River birch exhibits good heat tolerance in the Southeastern U.S. (USDA zones 4-8) and has fewer disease and pest problems than other birches (Betula spp.). Locate a diminutive ‘Little King’ adjacent to a deck or patio where it can easily viewed by family and guests. Add landscape lighting to highlight ‘Little King’ either in the garden or from inside your home any time of the year.

Grow it in full or partial sunlight (6-hours sunlight recommended). River birch is native to moist river bottom lands, and is not fussy about soil type. Soil pH should be slightly acidic to avoid pale green or chlorotic foliage in late summer from iron or manganese deficiency.

Availability is limited to specialty nurseries on the internet or through special ordering at your local nursery/garden center. It has been available since 1991 and more wholesale nurseries are growing it.

What Can Be Done About Phytophthora

Posted by Hugh on January 10th, 2012

Phytophthora disease (Phytophthora spp.) is the fatal cause of root rots, stem cankers and crown rots. Several hundred species of plants are susceptible, including redbuds, dogwoods, rhododendrons, camellias, white pines, firs, yews (Taxus spp.), and fruit trees. It thrives in warm moist saturated soils. Phytophthora may lie dormant in the soil for several years, waiting for a susceptible host plant and ideal environmental conditions.

Some common symptoms include yellow-green foliage, wilting, dead branches, and whole plant death. Infected leaves typically turn various shades of brown, die, and remain on the branches for several months.

Your best approach is to avoid the disease completely. Purchase only healthy trees and shrubs. Inspect the root ball for size dimension (compare to the top) and look for visible damage. Leave sick plants at the garden center.

Avoid plant stress by selecting the proper planting site. For example, most needle evergreens grow best in full sun, while broadleaf rhododendrons prefer partial sun. All demand a well-drained soil, preferably situated on a slight grade or slope. Do not plant in heavy clay or compacted poorly drained ground.

Prior to planting, remove all nylon and plastic burlap and twine around the root ball. Jute or cotton burlap and rope may be left around the rootball. Set most shrubs and trees at the same depth (as at the nursery). Fertilize plants in late winter at the proper amounts; overfeeding may worsen Phytophthora root rot infections. Water the plant(s) on site within three days after planting. Apply 2-3 inches of an organic mulch around the tree and do not pile mulch up around the trunk.

Once Phytophthora has been diagnosed, apply treatments of Subdue MAXX™ or Aliette™ fungicides in the spring and fall to prevent further disease spread. Fungicide treatments are quite expensive and removal of the sickly plant may be your best option.

Phalaenopsis Orchids Easy To Grow

Posted by Hugh on January 8th, 2012

Moth Orchids (Phalaenopsis) easy to grow

At one time, growing orchids was a hobby that only rich doctors, lawyers and fictional detectives could afford. Today, the very affordable “moth orchids” (Phalaenopsis spp.) are commonly available at supermarkets and big hardware chain stores at reasonable prices. They’re easy to grow and produce large showy flowers which bloom for two or more months.

Moth orchids can spend most of the spring and summer months outdoors beneath the dense leafy canopy of a shade tree. They come back indoors in early fall here in the Southern Appalachian region (USDA zones 6 and 7).

The winter season in most home is a tough environment for growing orchids. 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. Orchids are comfortable in home temperatures between 60 and 80 °F., but low room humidity is hostile to orchids. Room humidity as low as 10% is commonplace during the winter.

The bathroom and kitchen are the most humid rooms in the home, but outdoor light is usually limited. Moth orchids crave bright light but not direct sunlight. Sunlight intensity is weak and daylength is short in the Northern hemisphere between November through February.

Orchids are planted in special potting mixes containing coarse bark, sphagnum peat moss and perlite. Some mixes add charcoal for added drainage and to filter impurities. A good orchid potting mix should retain moisture for only a few days as their fleshy roots easily rot if the growing media is saturated for many days. Never leave a potted moth orchid standing in water.

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

Get Past The Winter Blahs With Paperwhite Narcissus

Posted by Hugh on January 4th, 2012

A wonderful, easy indoor gardening project this winter is to start a dish (pot) of paperwhite narcissus (Narcissus tazetta). Paperwhites make a lovely white centerpiece on your dining table. Paperwhite bulbs are outdoor hardy in USDA hardiness zones 8 – 10. Store the bulbs in a warm dry location such as on top of a refrigerator until you’re ready to plant them. Never allow the bulbs to freeze.

Fill a shallow container about 80% full with a porous sandy potting soil mix similar to planting cacti and succulents into. Set the bulbs a few inches apart on top of the soil and add coarse sand or colored aquarium gravel to the top of the container. Set the bowl or pot in a sunny house window until flowering begins.

Generally, the blooms may be forced in 3-4 weeks inside a warm sunny greenhouse. Begin by forcing bulbs in a cool room (or outdoors on mild days) at 50-60 degrees to stimulate root growth. As buds swell and open, move the pot to a cooler spot out of direct light to extend the life of the flowers. Floral life average 7-10 days.

The small trumpet shaped flowers are pure white and exude a strong sweet fragrance. Flower buds may “blast” (never open) if too hot and low humidity inside your home. Plant height varies from 1-2 feet depending on available light and temperature inside the room. Fewer hours of light per day means taller flowers and a greater need for staking. Rotate the container every few days to keep floral shoots growing straight.

You may purchase bulbs at many full-service local garden centers and Brent and Becky’s Bulbs on-line.

Volcano Mulching Harmful

Posted by Hugh on January 1st, 2012

Mulch Piled Up Around Tree

Piling up mulch around trees or shrubs, called “volcano mulching”, is a bad practice and is killing them. Perhaps you’ve seen a neighbor or a professional landscaper doing it, and assumed that it must be alright. It’s not!

The deep mulch pile smothers the natural buttress flair of the trunk which breathes and absorbs air for the rootsystem. The sugary sap underneath the thin bark skin is a food source for harmful insects which overwinter in the mulch piled around the bark. It also becomes a haven for critters, particularly rabbits and field mice.

Organic-based mulches aid to conserve soil moisture, moderate soil temperature extremes and reduce competition from weeds. It also keeps mowers and string weeders (“weed wackers”) away from potentially damaging the tree trunk.

Mulch depth is recommended at 2-3 inches and is distributed around the tree in the form of a donut. The bulk of the mulch should lay 3 or more inches away from the trunk and taper off near the tree’s dripline (outer extent of branches). Excessive depth of the mulch also promotes shallow rooting by reducing oxygen to the roots. Trees become more susceptible to prolonged periods of drought.

Organic mulches include pine bark, hardwood bark, chopped leaves, pine needles, and composted grass clippings.