Sunday, February 21, 2010

Thinking Spring-Color in the Garden Part I: Evergreens

Hinoki Cypress 'Crippsi'
The snow is finally starting to melt here in the northeast and thoughts of spring and returning to the garden are going through my mind.  Since evergreens are the "foundation" of the garden I am going to start with these wonderful all season interest plantings.  Evergreens of course are known for their ability to screen, add privacy to a spot and serve as the ultimate backbone of the garden.  Evergreens can sometimes be underestimated with the misunderstanding that they lack color and variety of texture but quite the opposite is true.  These dependable additions can add variety and color twelve months of the year.  The varieties I will be discussing do apply to zone 7 but are quite versatile and can be used in a number of climate zones.

Some of my favorite evergreens for brightening up any garden include the genus picea (spruce), chamaecyparis (cypress), juniperus (juniper) and cedrus (cedar).   In the spruce catergory-the Colorado Blue Spruce 'Hoopsi' is a favorite which grows to an average of fifteen feet in 10 years, stays at smaller size than an ordinary spruce and exhibits a characteristic  blue color throughout the year.  A smaller globe variety shrub form of the blue spruce is the 'Montgomery' Globe Spruce, another nice addition to any well lit garden. 

'Gold Mop' Cypress
The genus chamaecyparis includes my favorite golden additions to the garden including chamaecyparis pisifera 'Gold Mop'-an evergreen shrub growing to approximately three feet in height over time, much smaller than its predecessor the 'Gold Thread' cypress which can reach an eventual height of fifteen feet.   The 'Crippsi' Cypress is a lovely larger form of  chamaecyparis reaching fifteen to thirty feet over time and the dwarf golden form of hinoki cypress chamaecyparis obtusa 'Nana Aurea' only reaches about four feet and is a prize in the landscape.   I must not forget to mention another golden variety - a personal favorite of evergreen which is not a cypress but rather the genus picea (spruce) which I have recently added to my garden.   If you area a spruce enthusiast then the Oriental Gold Spruce, picea 'Skylands' is by all means one of the most beautiful evergreen trees imaginable and makes a grand stand alone statement to the evergreen-perennial garden.  

Juniperus 'Blue Star'
In the genus juniperus there are so many selections as well but the two I favor for instant color are juniperus 'blue star' - blue in color as the name indicates and juniperus 'gold lace'-not as golden as the 'gold mop' cypress but rather a mix of green and gold and bit more whispy in the garden.    Those of you who would like a little gold in the garden but not too much would prefer this particular evergreen. 

Deodara Cedar
Last but by no means least are the Cedars.  Cedrus deodara 'Aurea' is  magnificiant golden cedar which steals the show for any area where you have good lighting and plenty of space. This beauty can serve as an "anchor' plant for a foundation planting but allow it enough area to grow and make sure the center portion of the tree is planted an average of seven to ten feet away from the foundation (the further the better) to ensure proper distance from the exterior of your home- then enjoy this beauty.  Two other stand alone pieces in the genus cedrus are cedrus atlantica 'Glauca Pendula'  and cedrus atlantica 'Glauca'-both blue in color similar to the blue spruce however less of a "bottle brush" look to the needles as in the genus picea.  The weeping form (pendula) can be used as a foundation planting or in any garden and the later upright form can be used as a stand alone piece where they is plenty or room as it can also reach up to eighty feet in height under optimum conditions.  
Cedrus atlantica 'Pendula'
 (Weeping Blue Atlas Cedar)

I am hoping you have found the information in the above segment both informative and useful. This is the first in a series of three articles on color in the garden.  Parts II and III will focus on the usage of flowering shrubs and perennials to add everlasting color and interest to your landscape.

Author:Lee@A Guide To Northeastern Gardening Copyright 2010. All Rights Reserved

Wednesday, February 17, 2010

The Benefits of Mulching Your Garden

Mulching trees and shrubs is a good practice in keeping plants healthy and reducing landscape maintenance. Mulch helps conserve about 10 to 25 percent of the moisture lost from plants through evaporation and helps to keep the soil well aerated by reducing soil compaction that results from heavy rain. Mulch can also reduce water runoff and soil erosion as well as the likelihood of soil borne pathogens. Organic mulches decompose with time releasing small amounts of nutrients and organic matter into the soil. They help maintain a more uniform soil temperature (warmer in the winter and cooler in the summer) and provides an environment for beneficial soil microorganisms and earthworms.

Mulch serves its function best at a depth fo 2-4 inches and should be kept 1 to 2 inches from the base of plants to prevent bark decay. Keep in mind that mulch depth can depend on the type of material used and the drainage and moisture holding capacity of the soil. Sandy soils dry out quickly and often benefit from a slightly deeper mulch layer (3 to 4 inches). A site that stays moist may not benefit from mulching at all.

Mulch can be applied any time of the year, however the best time to mulch is late spring after the ground has thawed and the soil has warmed.  Mulching while the ground is still cold can delay soil warming and possibly inhibit plant growth. When fertilizing it is not necessary to remove the mulch as the nutrients will penetrate through the soil each time you water.

Practice good soil maintenance. Signs of plant stress could signal soil lacking in essential nutrients or components. A simple soil test can help to remedy this problem. Generally acidity of a soil can be controlled by adding lime to make it more basic or aluminum sulfate to increase acidity. Research the types of plants you have in order to determine the environment which is suitable.
Most evergreen trees and shrubs prefer a slightly acidic soil while many deciduous shrubs and perennials do not. Adding the same fertilizer to an entire garden can benefit some plants but can actually inhibit the absorption of nutrients in others. Ask your local garden center for advice on feeding your trees, shrubs and perennials.

Author:Lee@ A Guide To Northeastern Gardening Copyright 2010. All Rights Reserved

Garden Maintenance: General Tree & Shrub Care Information

Most evergreens can be pruned at any time of year except during severe heat and drought or within a month before the first frost.   Ideally the best time to prune evergreens is believed to be in March (late winter or early spring) before new growth starts. This also eliminates any winter burn that can occur during especially cold weather and gives the evergreen a good start for Spring.  Your flowering evergreens are an exception to this rule and should not be pruned until after blooming (late spring).  Evergreens such as pine, spruce and fir produce their new yearly growth in shoots called "candles".  In order to encourage more compact growth cut the tips of the candles back half way before the needles unfold.   No plant is completely maintenance free so keep your evergreens trimmed to their desired size. This will also keep them full and healthy and prevent thinning out. NOTE: Evergreens will shed their needles or foliage in the Fall/Spring to allow for new growth. If any branches appear brown or dead after planting or after winter, trim them off and allow the plant to rejuvenate.

Cherry Laurel
WINTER CARE: BROAD LEAVED EVERGREENS:   Some Broad-Leaved Evergreens such as Cherry, Skip or Mountain Laurel, Japanese Aucuba, Leucothoe, Skimmia, Boxwood, Holly and Rhododendron can be subject to winter burn from dehydration due to water loss in the case of a cold and dry winter. Care should be taken in the usage of an anti-desiccant such as ‘Wilt-Pruf” Spray which should be applied two to three times during the winter months throughout periods of cold and thaw.  There is also a new product on the market which lasts for three months with only one application.  Ask your landscape professional for more information.

PRUNING FLOWERING TREES & SHRUBS:   As a general rule prune flowering trees, shrubs and evergreens after the bloom.  Shrubs including Azalea, Rhododendron, Mountain Laurel, Cherry Laurel, Forsythia, Mockorange, Magnolia and Flowering Crabapple can be pruned in late Spring after bloom.  Flowering shrubs such as hydrangea bloom on the last years growth and will not bloom if cut back in Spring. There are some newer varieties of hydrangea such as the 'Endless Summer' Hydrangea which blooms on new and old wood and 'All Summer Beauty' which blooms on the new season's wood that can be pruned at any time and are a welcome addition to the garden.  Shrubs such as Spirea (except Bridal Wreath) and Barberry 'Royal Burgundy' or 'Rosy Glow' improve bloom and fullness when cut back in late winter-early spring (March) before they get their leaves in Spring. Renovate Lilac in winter and prune for shape after flowering in Spring. Prune roses in Spring to remove winter damage before new growth starts.    Buddlea (Butterfly Bush) should be pruned back in late winter-early spring while dormant for best bloom.

MOVING TREES: Trim (or move) deciduous trees in Fall after leaves have fallen and tree is dormant. Evergreens can be moved in either Spring or Fall and must be keep well watered.

PERENNIALS: Deadhead perennials such as salvia though out summer for continuous repeat blooms. In Fall perennials should be allowed to die back then remove any unwanted foliage. Pruning back perennials can be done in either late Fall or early Spring (March) before new growth appears but it is recommended in the Fall in order to prevent disease. Note: There are some perennials such as liriope (lillyturf) and coral bells (Heuchera) that can provide nice winter interest and benefit from pruning in Spring.

ORNAMENTAL GRASSES: Grasses should be cut back in late March before new growth appears. Leaving the grass during the winter provides nice interest to the garden and protects the root system as well.

FERTILIZING: Feed plants in Spring and Late Summer. Do not apply a full dose if feeding in the Fall apply a half dose for root feeding only. For new plantings allow the plantings to become established then apply a slow release organic fertilizer or apply a “starter” formula when planting. For established plants there are several products on the market but be careful not to buy a concentrated product that will burn the roots. A slow release or organic fertilizer such as Holly Tone is recommended.

WATERING:  As a general rule it is best to water less frequently and deep rather than everyday and shallow.  Water needs to get down to the roots of plants so it is recommended that trees, shrubs and perennials are watered every two to three days for approximately 40 minutes per area during Spring and Fall.  In cases of severe heat in summer months watering may be required more frequently.   Lawn areas in shade may require less watering and annuals may require daily watering at less time.  Monitor your plants frequently to adjust their watering accordingly.  It is also important that prior to winter that there is significant moisture around your plants before the ground freezes in order to ensure their health.  A well watered tree will over winter far better than a thirsty one and will not be as susceptible to winter frost damage.

LAWN CARE: Sod lawns can be planted anytime of year, preferably spring or fall. Avoid planting in extreme conditions of heat or cold and ensure proper irrigation to get your lawn established.  Seed lawns are best planted in the Fall (ideally between August 15 and October 15 here in zone 7) when temperatures are in the 60's and 70's.  Core Aeration and over-seeding are best done in the Fall to help rejuvenate a lawn and give it a healthy start for the following season. Your lawn should also have a regular maintenance program to keep it at its best. Ask your professional. 

INSECT CONTROL: Periodically check your plants for insect or fungal damage and treat if needed. It is advised to use a regular insect control maintenance program to keep your plantings healthy.

Author: Lee@A Guide To Northeastern Gardening Copyright 2010. All Rights Reserved