Early Detection & Treatment of Spruce Needle Cast Disease

Some spruce trees, such as Colorado Blue Spruce may be susceptible to environmental stress. The recent pattern of milder than usual winters and cool spring temperatures combined with wet conditions in the northeast have favored development of a fungal disease known as “needle cast”. Early detection and proper diagnosis is important in the treatment of this fungal disease and to ensure the health of your tree.

Identifying Needle Cast

The best proactive means for preventing needle cast disease is to plant your Blue Spruce in the proper location and provide proper care. Blue Spruce prefer to be located in a well-drained soil in an area of full sun, meaning the plant should be receiving at least six hours of sunlight daily. A southern or western exposure suits this best. Prevent irrigation from directly spraying on the foliage of the plant. Constant moisture on foliage or over-watering can be a direct invitation for needle cast. Drip irrigation is recommended where possible, allowing the soil to dry between watering. Proper planting height is of course also necessary. Plant the tree at grade or slightly above the grade so that the root flare is visible. Do not plant too deeply. It is best that the lower branches have some air circulation above the ground.

The type of needle cast affecting Colorado Blue Spruce in the northeast is mainly Rhizosphaera needle cast (caused by the fungus Rhizosphaera kalkhoffii). While some browning and dropping of older needles in spruce is common, needle cast disease is noted by a distinct brownish-purple discoloration which appears on needles (usually towards the bottom of the tree) with the eventual death and dropping of older needles. Newer current growth may show no signs of the disease.

Advanced Needle Cast Disease

Should your tree show signs of early needle cast, it is treatable. Needle cast can be effectively controlled with fungicides containing chlorothalonil. For Rhizosphaera needle cast, two properly-timed applications per year for at least two consecutive years (sometimes three) are required for control. The first application should occur when new needles are half elongated (around Memorial Day depending upon location) followed by a second application three to four weeks after the first. The timing of the two applications should be the same for the second and third year. Since needle cast is fungal and spread through spores, removal of branches showing early signs can prevent further infection.

As mentioned in the beginning of this article, the best method of preventing needle cast starts with proper planning, planting and monitoring. Early detection of any kind of disease leads to better results and remedies any further issues down the road. These tips also apply to dwarf forms of Blue Spruce, such as Picea pungens ‘Globosa’ (Globe Blue Spruce).

For more gardening tips Visit my Author Page

A Guide to Northeastern Gardening: Journeys of a Garden Designer Landscape Design Combinations
Dream, Garden, Grow!-Musings of a Lifetime Gardener

Lee Miller@Landscape Design By Lee 2020. All Rights Reserved.

Autumn Browning and Needle Shed on Hinoki Cypress

If the inner needles on your Hinoki Cypress (Chamaecyparis) are suddenly turning from a healthy looking green to shades of yellow, orange and brownish-red in autumn, there is little need for concern. Needle shed is all part of a natural process. Each year evergreens will produce new foliage in spring and part of the preparation process involves shedding their older foliage in the previous fall. Shedding of needles and foliage is a process that evergreens go through as a way of preparing for new growth once the weather warms. As the days become shorter and temperatures lower, evergreens go through a slight dormant period similar to deciduous trees and shrubs. Many evergreens such as Chamaecyparis (Hinoki Cypress), Thuja (Arborvitae), fir, pine, cedar, hemlock and spruce lose some of their needles every year and may go through a major shedding every three to five years.

Autumn Browning and Needle Shed Hinoki Cypress

To examine, look at your tree carefully. Older foliage is shed first so the losses should generally be from the inside out and not at the tips. Prior to shedding the needles appear from green to yellow, orange and eventually brown, remaining on the tree until the process is complete.  The actual amount of needle shed on the tree or shrub varies depending on the growing season, temperature changes and amount of rainfall, and can sometimes be sudden. Often the change is unnoticeable but generally the drier the season or more drastic the temperature change the more noticeable the needle shed, a natural cleaning process leading to new growth in the spring.

Hinoki Cypress Major Needle Shed Autumn

The sudden change in temperatures over the past couple of weeks here in the northeast has caused some of the Hinoki Cypress to go through a major shed. I do have concern over this particular Hinoki, which I have had for over twenty years. It does tend to get more yellowing/browning over the others, but normally comes back with a flush of new growth in spring. If desired, lightly brushing the inner portion of the plant will help to remove the older browned foliage. If concerned about any particular branches on your plant, scrape the bark with your fingernail down to the growing layer. If the branches are brown and brittle the area tested has met its demise. If there is presence of a green growing layer underneath the surface of the bark, the branch is indeed alive.

 Author:  Lee@Landscape Design By Lee, 2019, All Rights Reserved

Spring Maintenance of Birch, Boxwood and Hydrangea

Once mid-late spring rolls around, you may notice that some of your landscape plants are in need of some tender loving care. After the lack of snow in some parts of the northeast and prolonged frigid temperatures in the single digits this past winter season, certain plants have been more affected than others by the lack of insulation from snow cover and extreme cold. Another factor affecting the vitality of your plants could the abundant rainfall amounts hitting the eastern seaboard.

Winter Die Back on Weeping Birch

Birch trees are one species that the winter has especially taken a toll on. By this time in June, Birch trees should have pushed out most of their new foliage, but you may notice some bare branches and empty spots on your tree. If that is the case, gently scrape the bark or cut a tip off bare stems to see if there is any sign of green. If the cambium growing layer underneath the bark is green, give the tree a little more time to see if it will push out any new growth from those branches. If the layer below the bark is brown, remove the dead branch from the tree to help direct growing energy to where it is needed. Give the tree a good feeding (preferably a deep root application) and some time. The tree should gradually show signs of recovery and continue to regain its health.

Iron Deficiency on Boxwood

Boxwood is another plant which has been affected by the recent weather abnormalities. If your boxwood is looking a little paler than usual with some yellowing in the leaves, it could be a sign of iron deficiency. The abundance of rain here in the northeast has literally “washed” away much of the iron in the soil. Iron chlorosis can develop under conditions that reduce the availability of iron to the plant, such as a combination of cooler than normal temperatures and poor root aeration or soil drainage due to constant moisture. To remedy the lack of iron, apply a liquid iron solution to the soil around your plants. Most supplements will work over time to restore the plant back to good health.

Winter Die Back on Hydrangea

Hydrangea are another plant showing signs of winter damage over the past several years here in the northeast and over other parts of the country. If your Hydrangea is still showing bare stalks above new growth now in June, and stems appear dead, simply prune off the damaged wood to beneath the line of new foliage. As with most flowering plants, application of a plant food that is high in phosphorus in mid-late spring will encourage buds.

Routinely checking your garden in springtime can catch early signs of plant distress and help in avoiding more serious issues down the road. During springtime and throughout the ongoing growing season, early detection of plant issues is a worthwhile practice, After all, a little preventive care can go a long way!

For more gardening tips and design inspiration along with personal musings…

Visit my Author Page/Purchase My Books:
A Guide to Northeastern Gardening: Journeys of a Garden Designer Landscape Design Combinations
Dream, Garden, Grow!-Musings of a Lifetime Gardener

Lee Miller@Landscape Design By Lee 2019. All Rights Reserved.

Contagious Fungus Attacks Ornamental Pear Trees on Long Island

Ornamental Pear trees have been recently under attack from a hard to treat fungus known as Trellis rust. Originally from Europe, Trellis rust or European Pear Rust is caused by the rust fungus Gymnosporangium sabinae. The disease may present a serious health threat to members of the Pyrus species, including both ornamental and fruit pear types. Ornamental Pear trees have been popular trees planted for decades noted for their fast growth rate, tolerance of urban conditions, fairly compact shape and white blooms that appear in early spring. Unfortunately, hundreds of trees have been noted dying in Rockville Center and the disease has been spreading to the Nassau and Suffolk County areas of Long Island. The fungus has spread from the mid-western states to upstate New York and Connecticut over the past several years and seems to be getting progressively worse. According to horticulturists, part of the problem is that the trees have been over-planted, resulting in a rapid spreading of the disease.

Symptoms to look out for are yellow-orange leaf spots (see photograph), which develop into spores in late summer. The spores can be spread to other host plants by wind or to the roots if the trees are close enough together. The secondary host during the winter months is juniper, allowing the fungus to survive when the pear trees drop their leaves; hence, continuing the cycle in the spring.

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Photo Credit: MSU Cooperative Extension

If you spot damage on your tree, remove and destroy the infected leaves to prevent spores from spreading. If caught early enough, systemic and spray fungicides can be applied to inhibit the spread of the disease. Best preventive measures are to be alert in monitoring your trees, and when in doubt, call a tree professional.

Late Winter Bronzing of Evergreens-Is it Normal?

What is “winter bronzing”? While approaching the end of winter, some of your favorite evergreens may appear to take on a bronze appearance. You may be wondering. “Is this normal or is my plant dying?” Changing foliage color is a normal phenomena that affects some evergreens near the end of winter while seasons are transitioning. Freezing temperatures, followed by a warming trend, longer hours of sunlight, then more cold can trigger foliage to discolor. The color change is a reaction to low temperatures, winds and sunlight, causing mild desiccation of the needles or leaves, allowing the underlying colors to show through. This dulling of green foliage is more pronounced on plants that receive more sunlight. The result is commonly known as “winter bronzing”. The longer the ground is frozen and the more water that is evaporated from the plant than it can take in, the more pronounced the foliage will appear to turn from green to brown, bronze, or even orange or purple. This process is similar to why deciduous leaves change color in the fall. While the tree is going dormant for the winter months, chlorophyll production subsides and the true underlying colors of the leaves are revealed. 

Winter Bronzing of Evergreens

When can I expect my trees to look more normal? Once the temperatures rise and new growth is stimulated, the foliage will turn back to a more vibrant green. Broken or dead branches are different in that they are completely dried out and brown. Those branches should be pruned off the tree in late winter/early springtime to prevent any further damage. Any falling or divided tree leads can be arbor tied to secure them and encourage upright growth. Split branches can also be arbor tied together, and if caught in time the cambium growing layer of the tree can mend. In the photograph above, the center upright Western Arborvitae are displaying signs of bronzing with no evidence of  any completely browned or broken branches, both indications of a normal and healthy tree.

For more gardening tips and design ideas: My books on Amazon:

 Visit my Author Page

A Guide to Northeastern Gardening: Journeys of a Garden Designer  Landscape Design Combinations
Dream, Garden, Grow!-Musings of a Lifetime Gardener

Author:  Lee@Landscape Design By Lee 2018. All Rights Reserved.

Snow Warnings and Care of Landscape Plants

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March Snowstorm

The seasons have been shifting in the northeast, leaving many homeowners in much dismay when it comes to winter garden maintenance. Winter storms can hit late winter into early spring, causing more distress to plantings once they have experienced warmer than normal temperatures. As we await another winter storm, there are some precautions you can take to ensure the vitality of your landscape plants and protect them from possible damage.

SNOW WEIGHTED TREE BRANCHES: Most evergreen trees and shrubs can handle snow build-up on their branches, but in the instance of a heavy snow, the branches may become weighted down. Certain Arborvitae are susceptible to the weight of snow pulling down on them and may have already experienced sagging branches. Further damage can easily be avoided by wrapping the branches together with arbor tie. The cloth tie cannot be seen from the outside, will prevent future damage from another snow, and the tree will look unscathed.

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Arborvitae and Snow Care

BROKEN OR DAMAGED TREE BRANCHES: Before an approaching storm, try to walk outside and inspect trees and shrubs on your property for any broken or damaged branches. If you do spot a damaged branch, tie the two split halves together by wrapping them tightly together with arbor tie. Start by wrapping the two halves tightly together and continue wrapping above and below the crack for extra support. If caught in time, the cambium (or growing layer) of the plant will repair itself and fuse the two parts of the damaged branch together. I have personally saved split branches on holly, azalea and arborvitae using this technique and the plants have recovered beautifully. Identifying these issues now and tending to them prior to the snow can mean the survival of your plant.

arbor tie
Arbor Tied Split Branch on Holly

SNOW REMOVAL: While it is tempting to go outside and start removing snow from weighted branches it is also a good time to exercise caution. Under the snow-covered branches could also be a frozen layer of ice.  Any manipulating of the frozen branches could result in easy breakage and permanent damage to your tree.  A helpful tip is to very carefully dig snow from around trapped branches and allow them to spring back up on their own. Never shake branches with ice.  It is best to let nature take its course and allow thawing to occur. The branches will gradually regain their shape as the ice melts preventing any harm to your landscaping.

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Snow Removal From Branches

SPRING BULBS AND SNOW:  Just as your spring bulbs are emerging, a late winter snow storm in March can cause much distress and uncertainty. Besides having to tend with the snow, there is some reassuring news!  While mulch protects dormant bulbs from cold, once they start blooming, a covering of snow will act as an insulator. The snow will help to hold in the natural warmth from the soil and provide protection. Once the snow is gone, you can continue to enjoy your bulbs!

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Spring Bulbs and Snow Cover

As mentioned previously, plants are very resilient, and with a little care can bounce back and recover nicely after a major snow. With a March snow on the way, warmer days may not look promising at the moment, but Spring is right around the corner!

Informational Links:

A Guide to Northeastern Gardening on Facebook
Landscape Design by Lee on Facebook
A Guide to Northeastern Gardening Blog

NEGardening on Twitter

My Published Books: 

A Guide to Northeastern Gardening: Journeys of a Garden Designer

Landscape Design Combinations

Author:  Lee@Landscape Design By Lee 2017. All Rights Reserved.page-divider-autumn

Protecting Broad-leaved Evergreens for Winter: Anti-Desiccant Spray

The temperatures are dropping rapidly here in the northeast and it is time to apply anti-desiccant spray to your broad-leaved evergreens to protect them from winter damage.

What is desiccation?:   Certain broad-leaved evergreens are susceptible to winter burn and drying from harsh winter winds here on Long Island and anywhere where winter temperatures drop below freezing. Desiccation, or extreme drying is caused by moisture loss from the leaves by transpiration. A precautionary measure for this drying is the use of an anti-desiccant, which can help to prevent damage to your landscape plants.  Anti-desiccant spray is an organic based spray application that lasts for approximately three months throughout the winter, and helps to prevent water loss from your evergreens.

Which plants should be sprayed with an anti-desiccant?: Apply an anti-desiccant spray to your broad-leaved evergreens such as holly, rhododendron, cherry laurel, skip laurel, mountain laurel, Japanese skimmia, leucothoe, aucuba and boxwood when the daytime temperatures start falling below 50 degrees (around Thanksgiving here in zone 7 Long Island). Apply when the temperatures are above freezing and there is no threat of rain or frost within 24 hours. (This tip applies to areas going into their winter season-temperatures dropping below freezing: 0 degrees Celsius or 32 degrees Fahrenheit.)

When to Apply: Apply anti-desiccant when the daytime temperatures start falling below 50 degrees (late fall/early winter). Apply when the temperatures are above freezing and there is no threat of rain or frost within 24 hours.

Dangers: Be sure to read all directions on the label since anti-desiccants can cause photo toxicity on some narrow needled evergreens such as Arborvitae and Spruce that could cause more harm than winter burn.  Spraying in freezing temperatures will do harm to the plant.  Do not spray in freezing temperatures and allow time to dry before temperatures drop below 32oF or 0oC.

How often should I apply anti-desiccant?:  Sudden warm spells can trigger your evergreens to open their pores allowing for more water loss. If there is a winter thaw part way through the season it is recommended to re-spray your plants but only if the temperatures are to remain above freezing for at least 24 hours.

Where do I purchase anti-desiccant?:  The most commonly used brands of anti-desiccant are Wilt-Pruf, Vapor Guard and Transfilm that can be found in nurseries and garden centers. There is a new brand of anti-desiccant on the market which requires only one application. Ask your landscape professional for more information.

Informational Links:
A Guide to Northeastern Gardening on Facebook
Landscape Design by Lee on Facebook

NEGardening on Twitter

My Published Book: A Guide to Northeastern Gardening: Journeys of a Garden Designer on Amazon

Author:  Lee@Landscape Design By Lee 2016. All Rights Reserved.

Book Announcement! My First Published Book!

FotorCreated BOOK PROMO 2 600 pixAfter two years of working on my book I am excited to announce that it is finally published! A Guide to Northeastern Gardening: Journeys of a Garden Designer is a comprehensive guide to gardening in plant hardiness zones 3-9.  My goal for the book is to share information on a number of gardening topics based on my experiences as a landscape designer over the years.BOOK PHOTO

A Little Bit About the Book:

A Guide to Northeastern Gardening is a comprehensive guide of valuable information on plants hardy in a range of zones from 3-9, and gardening techniques backed up by my own personal experiences as a professional landscape designer, along with answers to frequently asked questions. Learn about landscape design principles, butterfly gardening, deer resistant plants, long blooming perennials, globe and weeping evergreens, flowering trees and shrubs, native plantings, shade gardening and more. Whether you are a novice or experienced gardener, A Guide to Northeastern Gardening will help you to create your own dream garden. Come along on my journey into the world of gardening!

A Little Bit About the Author:

Lee Miller is a professional landscape/garden designer involved in the horticultural industry since 1996. Having started a gardening blog in 2010, she is the author of over 150 articles on general gardening, landscape design principles, gardening tips, planting, pruning, garden maintenance, feature plants and more. Her published book, “A Guide to Northeastern Gardening”, is an accumulation of information touching on a wide variety of gardening topics, all backed up by her own personal experiences.

Previews and further information are available on the following links:

Updated for 2016: Now in Amazon Softcover!

Amazon Kindle

Also here is a link to the full story behind the author and the book. I hope to share my gardening experiences with you!

As Always…Happy Gardening!

2015 Lee@ A Guide to Landscape Design & Maintenance.

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Dormant Oil Application in October: Protection from Insect Damage for your Landscape Trees & Shrubs

Dormant Oil is a known application that is sprayed on landscape trees and shrubs in fall to help protect them from overwinter damage from insects. Prepared from a mixture of highly refined petroleum oils combined with an emulsifying agent, dormant oil can be mixed with water and sprayed on trees killing exposed insects and mites by either suffocating them or destroying internal cells. These oils are effective in controlling most species of scales and mites that overwinter as nymphs or adults such as cottony maple scale, obscure scale, euonymus scale and lecanium scale which can do early damage. Dormant Oil is also effective on insect eggs that are laid in September and overwinter such as aphids, leafrollers, Spruce Spider Mite, Honeylocust Mite and European Red Mite. Dormant Oils are effective for both immediate and preventive care and have been developed to be less harmful to beneficial insects.   They are also safe for birds, humans and other mammals.

dormant oil
UC Statewide Integrated Pest Management Program

When to Apply:  Dormant oil applications should be applied in fall when temperatures remain in the 50’s at night (Early October) and must be done when temperatures stay above freezing for 24 hours. Dormant Oil is also best applied on a clear day with no wind and no threat of rain within a least six hours so that the oil can dry.  It is preferable to choose a time when no rain is in the forecast for a few days to ensure effectiveness.

Warnings:  Be sure to follow all label directions because oil sprays may damage certain plants, including Japanese maple, Eastern Redbud, sugar maple and Amur maple.  It can also cause the foliage (needles) of Colorado blue spruce to become discolored (change from blue to green) since the pigment is formed from the oils on the surface of the plant.  When in doubt consult with your landscape professional.

Dormant Oil when applied correctly will help to protect your trees and shrubs from winter and early spring harm from a variety of damaging insects and will ensure the health and vitality of your landscaping.

For more information on dormant oil application visit:  Colorado State University horticulture Insect Control

As Always..Happy Gardening!

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