Friday, December 15, 2017

Poinsettias in Scarlet Bloom at the Durham VA Medical Center

Photo archive by Marcia Loudon, Heritage Garden Club.
The Durham Veterans Affairs Medical Center is again in holiday scarlet bloom with poinsettias thanks to the sponsorship of the Forest Hills Garden Club and fellow members of the Durham Garden Clubs participating in the 2017 Poinsettia Project for Veterans.

Dr. Sue Woods, President of Forest Hills Garden Club, and Treasurer Moe Berry spearheaded the Poinsettia Project, assuming the mantle held and created by the Heritage Garden Club. This year's poinsettias totaled 64 plants. Each of these contained a plant tag honoring a US service member whom the sponsor recognized with their plant purchase.

As with tradition, at New Year's the 2017 holiday poinsettias will be distributed to patients in residence and staff at the VA Medical Center. Many of the keepers are able to grow the plants all year and are deeply appreciative of the gift, according to Woods.

Members of the Forest Hills Garden Club and Junior Garden Club ready to decorate the VA Chapel.
Photo by the Forest Hills Garden Club.

Wednesday, December 13, 2017

Protecting Plants from Cold Damage

Water loss is the main concern in the
garden during winter months.
Slow drip water to woody plants and water
cool grasses when precipitation is scarce.
During the winter months it is necessary to offer protection to certain North Carolina landscape plants. Winter protection does not mean to keep plants warm, as this is virtually impossible but to provide protection from damaging wind, heavy snow and ice, the alternate freezing and thawing of the soil beneath the plants and heat from the sun on very cold days.

Protection should be offered to evergreen plants by reducing water loss. Plants transpire water through their leaves. Evergreens continue to lose water during the winter, therefore moisture must be taken up by the plants' roots. Homeowners are more conscious of watering shrubs during the summer months and often this garden chore is neglected during cold weather. The roots will absorb moisture when it is available but when the ground is frozen or during a dry period the moisture is not available. The plants continue to transpire water but at this time draws moisture from living cells. If too much is given off from this source the cell dies. Consequently leaves brown out and die.

High winds and a warm sun on cold days result in a higher rate of water transpiration. Protection could be offered by planting susceptible plants in a sheltered location and providing additional water during dry periods or prior to hard freezes.

Foundation plantings are often injured by ice and snow falling from the roof on their frozen branches. It is sometimes necessary to construct a temporary shelter for shrubs in a precarious situation.

Wide tape or cloth can simply be wrapped around an evergreen to prevent broken branches. This is quite helpful to boxwoods and arborvitaes. If branches are bent and broken over by heavy ice or snow it is advisable to wait a few days before pruning and cleaning up. Often branches will recover to a degree of satisfaction on their own--so don't be hasty to prune drooping limbs.

An additional layer of mulch is usually recommended during winter months after the first freeze. Mulches will reduce water loss from the soil thus aiding in transpiration, and also reduce 'heaving' of the soil as the soil freezes and thaws.

To protect plants from cold damage, the following 6 steps are suggested:
  1. Plant only varieties that are hardy to your area.
  2. If you have a choice, locate less hardy plants in the highest part of the yard. Cold air settles to the lowest part of the yard.
  3. Protect plants from cold wind. A fence or tall evergreen hedge of trees or shrubs gives good protection.
  4. Shade plants from direct winter sun, especially early morning sun. Plants that freeze slowly and thaw slowly will be damaged the least. Obviously, the south side of the house with no shade is the worse place for tender plants.
  5. Stop feeding plants quickly-available nitrogen in late summer. Let them "harden off" before cold weather.
  6. A covering of plastic is excellent protection. Build a frame over the plant or plants, cover with plastic and seal plastic to the ground with soil. Shade plastic to keep temperature from building up inside. This plastic traps moisture and warm air as it radiates from the soil. It also knocks off cold wind. Be certain not to allow plastic to come in contact with plants.

Repair to Storm Damaged Plants

Knowing how and when to offer first aid to an ice, snow, or wind damaged plant will often save the plant from future decay and possible loss. Do not be in a hurry to start pruning a branch which is bent out of shape. Often in a few days following the damage the plant will straighten up on its own.

Broken limbs can be pruned immediately. Make clean cuts with sharp tools. If the plant is completely misshapen after the corrective pruning - consider pruning the entire plant where the subsequent growth will be in balance.

Trees can be straightened by cabling or guying. Straighten them by attaching a cable or guy about 3⁄4 of the way up - pulling them back into position. Be certain to pad the tree to protect against wire damage.

Trees which are uprooted should be immediately straightened and staked. Remove any damaged roots or limbs by pruning. Keep the tree mulched and watered during stress periods.

Author: Kim Powell, Spec (Commercial Landscaping)
Horticultural Science Publication date: Sept. 30, 1993

Thursday, December 7, 2017

Pathogen Spotlight: Phomopsis Blight of Juniper

Phomopsis blight is a serious disease problem on eastern red cedar in Missouri. The fungal disease, caused byPhomopsis juniperovora, is widespread in this region and can infect arborvitae and cypress as well as juniper. Phomopsis is more of a problem on junipers in landscape plantings because young tissue is most seriously infected. Older plants are seldom killed by Phomopsis, thus it is not a concern in natural stands of juniper.
Yellowing juniper tips (Juniperus) showing early signs of phomopsis blight.
Symptoms and Diagnosis

The first sign of infection is the browning of needle tips. New shoots, in the yellow-green stage, will brown and die in their first summer. Progressive dieback follows, eventually killing an entire branch by girdling the stem. The fungus will progress to the main stem and can infect and girdle stems less than 1/2 inch in diameter. Infected needles turn light green, then reddish-brown, and finally an ashen gray.

Life Cycle

Phomopsis overwinters on needles and stems of young trees that were infected the previous year. The fungus is most abundant on dead tissue that has become ashen gray in color. Infective spores are dispersed by rain splash. Only seven hours of 100% humidity are needed for infection to occur when temperatures are 75 degrees F.

Integrated Pest Management Strategies

1. Prune infected branches to prevent the spread of the disease. Remove dead tissue as well. The fungus can produce infective spores for up to 2 years in dead parts of infected plants. Prune in late summer when the weather is dry.

2. Plant resistant evergreens. Susceptibility to Phomopsis blight varies considerably among junipers. Ask for resistant stock at your garden or landscape center or consider planting another type of evergreen.

3. Fungicides. Bordeaux mixture, other copper-based fungicides, and mancozeb are labeled for use on Phomopsis. These fungicides can be applied 3–4 times in the spring, at 10–14 day intervals to protect the new growth. They can be used anytime a flush of new growth occurs. Once the new growth matures in midsummer, discontinue further applications.
Organic Strategies
Strategies 1 and 2 are strictly organic approaches. Of the fungicides mentioned in Strategy 3, consult the Organic Materials Review Institute (OMRI™) for appropriate organic copper products.

Friday, December 1, 2017

Garden Spotlight: 10 Gardens That Glitter with Holiday Lights and Cheer

Looking for design inspiration for your Christmas outdoor display?
See the gardens highlighted in Garden Destinations:
Pictured: Shore Acres Garden – Holiday Lights in Coos Bay, Oregon