Friday, November 5, 2010

Tree Planting Notes

The dark line around the trunk shows the original soil line

Often while doing a garden renovation will come across trees that have been improperly planted.  The usual instruction from nurseries is to plant the tree at the same soil level as it arrives to you in the container.  But beware -- this is not what you should always do.  The landscaper who planted this tree (see photo on the right) had in good faith followed nursery instructions -- and effectively buried 6" of trunk below the ground.  

The black line around the trunk shows where the soil level had been.  Planting a tree at the wrong depth causes the roots to girdle (run in a circular direction around the trunk -- instead of laterally out from the trunk); this girdling strangles the tree.  It also causes the trunk that is buried to rot; this part of the tree trunk (the part above "the flare" -- more about this later) is not made to be buried/wet -- so it rots -- and is more prone to disease, fungus and insect problems.

Whether planting a B&B (ball and burlap) tree or a tree in a black liner container -- you should always remove the soil around the trunk to the "flare." 

What is the flare?
It is the part of the tree that abruptly or gradually flares out -- like a woman's hip -- from the trunk.

The trunk and "the flare"

If the flare is buried you can do a "Root Collar Excavation." 

Next Blog:  Root Collar Excavation

Questions?  Contact me:

Thursday, November 4, 2010

Root Pruning Container Plants

How to Root Prune Container Trees & Plants

Spread tarp under planter to catch debris
Tree roots grow laterally-- 18" - 24" below the surface of the soil.  Unlike trees and plants that grow in-ground, container plant roots eventually hit the barrier of the container and die.**  

Brown  matted dead roots are incapable of taking up nutrition/oxygen or adequate water.  You can water and feed these plants constantly  but the plant will continue to deteriorate.   Transplanting to a larger container is an option.  Often, however, this is not possible and can be very costly.   An excellent option is pruning the plant's roots - this will completely
revitalize it.

The best time to do this is fall and late winter/early spring.  As long as the container/soil is not frozen.  (It is not recommended for summer -- for obvious reasons.)
Insert saw blade 2" from edge of planter

What you will need:
a fine tooth sharp saw
 -- blade at least 8-10" long
or Sawzall w/12" wood blade
sharp hand shovel (See link below)
potting soil
PHC BioPak Plus (see link below)
blue tarp
5 gallon bucket
tablespoon measure

The preliminary cut is  2" in from container edge; saw completely around the perimeter -- to  depth of the blade.  If you run into a large root --  go around it.  Using a sharp-edged hand shovel, remove the cut soil and roots.  Do not pull or yank the roots out from the root ball; if necessary cut whatever roots are still protruding.   After the first several inches are removed, continue to saw; remove material until you reach 18" depth (for a 24" planter; less for more shallow planters.  But don't worry if you can't get to 18" -  go as deeply as you can.)

This is how it will look after the pruning

Have ready the replacement mix: 1/2 potting soil with 1/2 compost/-- combine well.  Add the mixture --gently pressing in with fingertips to fill the planter.  Be gentle but firm.  You want to make sure there are no air pockets but after you add the water mixture you will be able to see where you will need to add more soil. 

Do not add more soil to the top of the root ball unless the "flare" of the tree is visible above the soil level -- then you can add a bit to the top. (see Rooftops Gardening:  Planting a tree -- the right way.)

In the bottom of your 5-gallon bucket add 6 tablespoons of the PHC Biopak powder.  Add water/mix thoroughly.  Water with this solution -- slowly -- allowing the solution to drain thru.  Add more soil mixture if needed -- water with solution again.  The soil should be completely drenched.  Mulch -- 1-2" depth.  Do not put mulch against the trunk of the tree.  Leave at least three inches around the perimeter.  Do not let the planter dry out.  Repeat solution treatment every two weeks until the soil freezes.  Repeat solution treatment in spring as soon as the planter thaws. 

Add soil and compost mixture

Water soluable solution specifically designed to reduce plant stress

**For this reason it is recommended that you plant trees and shrubs in planters that are at least 24" high -- but more importantly -- ones that are nice and wide to accomodate the lateral root development.  The depth of the planter is not nearly as important as the width. 

  • As you remove the dead materail along the perimeter -- if you come to a large root -- over 1/2" or more in diameter -- don't remove; go around it.   
  • Do not prune the crown/top of the tree at this point.  If you are doing the root pruning in fall -- wait until the tree is leafed out and then prune. 
Questons?  Contact me

See link below
A.M. Leonard for garden tools and
and Plant Health Care products
Alternative to PHC Biopak Plus 3-0-20 is:
   Bio-Plex Transplant Concentrate & Plant Enhancer
   or PHC Tree Saver
(Both are available from A.M. Leonard)
See also:  A.M. Leonard
"Trenching Shovel"  and "Soil Knife"

Saturday, September 18, 2010

Bartlett Tree Experts

I had the great honor of going to the Bartlett Tree Experts Research Field Days at the Bartlett Arboretum in Charlotte, North Carolina (September 14-15, 2010).  I was invited by the NYC sales rep for Bartlett -- Kevin Kenney -- who is probably the best tree man on the East Coast.  The arboretum is 400 acres (the largest private arboretum in the US) and contains over 8,000 accessioned plants.  (There is a link to their website at the bottom of the page.) 

Kevin Kenney has been an invaluable partner to me in my NYC landsape design business. Because container gardens are at special risk (the fact they are planted in containers and not in ground) means that they have to be watched after more carefully.  They are susceptible to many more problems and environmental dangers.  Bartlett has special tree and woody plant programs that monitor and treat/fertilize rooftop gardens and terrace gardens.   Bartlett is a leader in organic pest and disease control research -- and treating gardens with organic materials is important to my customers.

Kevin Kenney
The field days provide arborists, landscapers, landscape architects, students, teachers and other landscape professionals, as well as private land owners an opportunity to take a look at demonstration areas of the Bartlett research labs and to see the new programs for managment of woody landscape plants.  Some of the demonstrations included Sidewalk plots -- of particular interest to NYC gardeners;
Root barriers; structural soil and soil management procedures; tree preservation; pruning; invasive species management; and the new and exciting BioChar research. (This amazing product not yet on the market -- but we saw some of their test sites and the growth/health rate of the BioChar as opposed to the control groups was pretty astonishing.)

The next day we visited the Plant Diagnosis Clinic run by Eric Honeycutt and Lorraine Graney.  Lorraine sliced into a small twig that had tiny holes in the bark (under the microscope with images projected onto a screen) to show us the tiny but voracious beetle and larvae imbedded in the twig tissue.  Each year the clinic receives more than 6,000 plant samples for analysis for insect pests, diseases and cultural and environmental problems.

Later on Dr. Don Booth demonstrated some research being done on natural predators in the garden -- wasps that pierce the backs of leaf destroying caterpillers -- laying  their eggs into the caterpiller's back. As the egg develops it eats the host caterpiller.    And how to make sure ladybugs once released don't fly away before eating the aphids you want them to eat.  (You spray a little sweet soda (non-caffeine) -- onto the plant -- and then release the ladybugs onto the plant --they go straight to the Fresca and then go on to eat the aphids.)  Dr. Booth talked extensively about Bartlett's pioneering research into organic pest and disease control. He pointed to one of the plastic gallon jugs on his worktable telling us "You could drink a whole gallon of this straight down and nothing would happen to you." 

Dr.  Booth

Bartlett's Wayne Dubin & Kevin Kenney's team planted the initial crop of 16 trees at the World Trade Center Memorial site.  "They are the most cared for trees in the world," Kevin said.  The balance of the trees (there will be 375 of them total) -- are being grown and cared for at a nursery in New Jersey.  Wayne Dubin (Bartlett VP and Division Manager) showed me photos of these -- all in specially designed wood containers.  "They will be broken out of the wood and placed into special custom constructed steel containers for safe transit to the Memorial site, and then craned down into each plot that has been pre-dug for that particular tree," Wayne explained.

"Our assessment of these trees includes the use of custom monitors (ribbons) that let us know about soil moisture and temperature, which turns the irrigation system on and off. Our onsite technician, Jason Bond, is a Board Certified Master Arborist," Wayne said.  "He carries out daily inspections and treatments (when necessary) which are then recorded into an online database available for review by the owners and consulting arborist.  The trees are protected from pest problems, cultural issues, and receive soil treatments to enhance nutrient availaility."
Wayne Dubin Bartlett VP
and Division Mgr.

 Soil compaction around tree roots is a problem not only for NYC street trees but for all trees -- parks, recreation areas, backyards -- anywhere  people walk, ride, or drive vehicles thru.  Bartlett conducts extensive research into the best "sidewalk" material to use around trees.  Trees require water obviously -- but their roots are shallow (the better to also absorb much needed oxygen) -- so that it's easy to damage them.  Take a look at the tree photo below:

To protect a tree's roots -- at least a 4" layer of mulch must be applied to the base of the tree that extends out to the drip line of the tree.  Care must be taken not to apply the mulch next to the trunk, leaving at least 1 foot clear of the flare.  

This demonstration site shows the work done to find root rot -- a small hole is drilled into various spots in the roots.  When the drill hits a soft spot -- that's where the rot is present.  

The beautiful arboretum -- some photos of the landscape:

No expense was spared, no comfort ignored  -- many thanks to the Bartlett Tree Experts staff for a unique educational experience.

Monday, February 2, 2009

Crabapple Tree Woes

The gall after spring rain

I've never used Crab Apple trees in any of my container gardens, but a customer really wanted one -- and I was excited to see how a tree like this would do in a planter.

Crabapples are part of the Rose family, genus malus. Any fruit over two inches in diameter is considered an apple. I found the perfect tree at one of my nurseries in Dix Hills. While the fruit on it was more like a rose hip than an apple, this one was the perfect size with a lovely, elegant shape.
My customers were delighted. But a few months later I got the call that there was something terribly wrong with their crabapple. (See photo above of what they saw; the top photo is the gall just after rain in spring.) From their description was pretty sure it was cedar apple rust.

Cedar Apple Rust is a fungus that starts on cedar or juniper trees and jumps to apple (and other fruit bearing trees). It's a rough looking brownish gall until spring rains hatch it into a mushroomy orange "thing" that bursts open. The fungus spores travel over large areas (miles) and come to rest on apple trees, discoloring them and, over time, stunting the fruit and the tree.

Inspecting every cedar and juniper within a several mile range of downtown NYC was not an option (pulling off and destroying the gall before it "hatches" is one preventative measure). Instead, we ordered some Kop-R-Spray (considered to be the most effective stuff on the market) from California. It couldn't be shipped by air (regulations) but when it arrived there was enough for us to open our own cedar apple rust spraying company.
After spraying, the fungus disappeared within a week -- & it seemed like a miracle. Next spraying: Spring after the first really good rain hatches its batch of fungi -- some no doubt heading directly for our little crabapple on Broome Street. We're ready for them this time.

Sunday, January 28, 2007

Roof Gardens and Weight Allowances

The design of your garden will depend completely on how much weight the roof structure can sustain. In older buildings, this is a real challenge. In new and renovated buildings, developers are aware that end users of a terrace space expect the amenities of rooftop living: including but not limited to: hot tubs, large containers to sustain specimen trees, pergolas, etc.

Not everyone is so lucky. Most rooftop gardeners will have to stay strictly within the weight limits of the building. If there are no such specifications, a structural engineer will have to be hired to determine the amount of weight the roof can support. In addition, the roofing contractor who installed the waterproof membrane that protects the building from water damage, has a specific set of requirements to ensure that the warranty provisions are not violated. The building management company may have this information available.

Landscape designers and related professionals will not undertake a project of any size without weight allowance information. The liability for damages can be enormous for everyone.

Having said all this, the weight of planters can be manipulated through various methods to lighten the load. Everything from lightweight planters to increasing drainage levels to manipulations of the soil mix. The general rule is to stay within 40 to 60 lbs per square foot. But this is just an average. Some buildings will specify a lesser weight amount. This includes the weight of the planter, the soil, and the plant. Some specifications calculate the amount of weight the entire roof can sustain, while others differentiate areas of the roof that can sustain heavier weights because of load bearing beams.

If you would like all the calculations to determine weights, please email me and I'll send them out to you.

Visit the website:

Great Resource:
Planter Resource in New York City
28th Street betw 6th & 7th Avenues
(closer to 7th)

Saturday, January 27, 2007

Cleaning Concrete Pavers

Concrete pavers are routinely specified for roofdecks, terraces and backyards. While they are long-lasting and relatively cost effective, they are also porous and require maintenance. Rust, grease, wine, white residue, dirt/soot, and mold stains on your pavers will ruin the look of your garden space. (Photo above shows pavers being installed.)

Some professionals recommend sealing the pavers to reduce dirt & grease absorption. We have never found a sealer that lasts longer than a year, in spite of claims by various manufacturers. Application and re-application can become very expensive (depending on the size of your roof area -- between $1500 to $2500 + per application).

We have also tried many cleaning products costing from $20 to $200+ but have never found a product better than baking soda and a mild solution of bleach.

Concrete pavers come in many colors and are made by adding pigment to the concrete mix during manufacturing. This means that the color runs thru the entire paver and is unlikely to lose color during cleaning. **But please do a test cleaning on a paver before you do your entire roof surface.

What you will need:
5 gallon bucket of water with 1/2 cup of bleach
Baking soda
Long handled stiff bristled plastic scrub brush (do not use a metal brush).

Sprinkle a liberal amount of baking soda onto pavers;
dip brush in bleach solution and scrub in 8' x 8' sections; allow to sit on entire surface area for a few minutes, then rinse thoroughly. Although you can definitely spot clean a paver, it is better to clean the entire roof surface -- or large areas at a time -- to avoid variation of look from section to section.

To avoid bleach splashing onto your pots & planters, place a large (opened) cardboard box upright against each planter. Scrub/rinse, re-place the cardboard against next planter.

For your information: The rust is caused by the iron oxide minerals in the paver combined with water -- and the metal railings, furniture and fixtures in your garden. The white residue, called efflorescence, is the lime released within the concrete carried by water to the surface of the paver.

Never use acid cleaners on your pavers.

Clean grease stains immediately. Wipe off excess oil; apply detergent and allow it to sit for 10 minutes; then wash with hot water. If there is still a stain, scrub with bleach and baking soda. Never use amonia and bleach together; the fumes caused by this combination are dangerous to inhale.

Do not use this cleaning method on granite, marble, or other natural stone products. These products can be fragile and require a professional stone cleaner or restorer.

NEXT POST: Roof gardens and weight allowances
Visit the website:

Friday, January 26, 2007

NYC Roof Gardens in Winter

Winter Gardens

NYC: Unbelievable cold today (9 degrees with face numbing windchill). Tomorrow the forecast is 40 and warmer on Sunday. It's been an incredibly mild winter in most of the Northeast (except for today) -- but not much rain since winter began.
In times of mild weather and little rain, containers can dry out. Last February and March, for instance, the temperatures were mild but only a few inches of rain. We lost two large Cryptomeria trees (See photo above; tree on left/center is the Cryptomeria) -- not because of severe cold -- the reason usually cited for Cryptomeria death -- but because of lack of water in late winter/early spring. Since irrigation systems are not turned on until all danger of frost is over, most container gardens -- and even some inground ones -- may require hand watering when temperatures are mild and there isn't much precipitation. When it's supposed to be winter ... frozen; dormant ... but it's not really.

Use the "finger test" to determine if you do need to water. If the surface soil to 2" is dry, water deeply, until the water runs out of the bottom of the container. Avoid sprinkling or spraying the soil. Roots gravitate toward water (and oxygen) and if water penetrates to only within a few inches of the surface, you'll have roots growing up -- and not down and out, the way they are supposed to grow. Always water deeply with an open hose (remove the nozzle). To make certain the water is penetrating all part of the container or if the soil is very dry, water once thoroughly and then repeat.

Next Post: How to clean cement pavers
Email me at: with questions or comments
Visit the website:

Great Garden Resources:
Trellis Structures in E. Templeton, MA
Beautifully made arbors, pergolas, and trellises at reasonable prices.
They ship most items, but will deliver to the city on larger and custom

Bottega Furniture in Dayton, OH
Handmade outdoor furniture made of Ipe; unusual design, elegant,
but sturdy. Met thm at the NYC Home&Garden show a few years
ago. Wonderful stuff.