Leyland cypress (X Cupressocyparis leylandii) is an intergeneric (of two separate genera) cross between Monterey cypress (Cupressus macrocarpa) and Alaska Cedar (Chamaecyparis nootkatensis) that originated in England  before 1900.

Leylands Cypress are safe to zone 6 (Long Island), while Thuja green Giant are cold-hardy  to zone 5 (CT, RI, MA, etc).

FERTILIZER

In the Hamptons area of Long Island, I buy from  LESCO which is now John Deere or  Lynches in Southampton and get slow release, 14-14-14, 40 lb bags are approx. They key is to key slow release!

Use 1 lb for each inch of trunk diameter, so  a 12' tree gets 3 16 oz drink cups around the rootball, NOT DOWN IN THE HOLE. It will feed for 4 months if you use it as top dressing like it should be. One bag will do 10 12' Leylands.

In the south I like Nursery Special by STA-GREEN. For Ball and Burlap (field-grown) trees, I add all I can hold in two hands around the  rootball for the 7' size tree, twice that for 10' trees.

For fall planting, Nellie Stevens or Dan Fenton hollies or evergreens like Leyland Cypress or Thuja Green Giant proper fertilizer is very important as those trees stay active all winter.

If you plant decidious in the fall , you won't need quite as much slow-release fertilizer since they go dormant in winter. Apply all you can hold in two hands around the drip line of the tree. 

Be sure and use a  slow-release fertilizer like Nursery Special by STA-GREEN for newly planted trees. You could actually stress your new trees with fast release nitrogen fertilizer because that encourages the top of the tree to grow. If you have ball and burlap, field grown trees you have 100% of the trees limbs and trunk, and maybe only 80% of the root system, so you need some nitrogen but not allot. The first two years after a tree is planted, they should be fertilized twice a year, April 1 and September 1.   The key is the slow release of the Nitrogen. I buy my fertilizer at Hill's lawn and garden in Thomasville, NC.

Leyland Cypress Sunlight Requirement

Leyland Cypress and Thuja Green Giant trees will tolerate partial shade. We want to discuss the canopy situation, shade on one side, even how being in the North or South can effect a shady planting site.  We also will cover the symptoms of too much shade, providing light by pruning the offending shade trees and also a good substitute for shady locations.

A straight overhead canopy of shade is not the preferred situation for Leyland Cypress and Thuja Green Giant trees. The absolute worse situation is an overhead pine or evergreen canopy, because the trees under an evergreen canopy don’t even get light during winter. If that is your application, don’t plant there. Sometimes it cannot be avoided. For example, in Long Island and in the Hamptons area, some neighborhood have rules about what can be cut and are very strict about cutting native trees to replace with anything not native to the area. Even so, I am not recommending planting Leyland Cypress or Thuja Green Giant trees under a canopy.  I have planted these varieties under a canopy that was very high and still it effects the trees.

Northern locations tolerate shade trees better than southern locations! If the trees bring the shade are deciduous tress, at least after those canopy trees shed their leaves, the Leyland Cypress trees will get full sun all winter. This is more beneficial from NY and northward than in southern states, because they shed one month earlier in fall than in the south and don’t green up till one month later than southern deciduous trees. On Long Island, Thuja Green Giant or Leyland Cypress trees planted under a partial canopy of scrub oaks may get full sun for seven months of winter before leaves re-appear, whereas southern states with a similar situation may only provide five months of full sun. Shade on one side of your row is normally fine, because your Leyland Cypress trees will still get the powerful straight overhead sunlight. Thuja Green Giant or Leyland Cypress trees can grow three feet per year if fertilized properly, so remember if there are slower growing trees shading on one side, The Thuja Green Giants or Leyland Cypress will out-grow the shading trees in most cases and will have more sun after that time.

The main symptom of too much shade on Leyland Cypress and Thuja Green Gants is the trees thin out. When you first plant them if Ball and Burlap field grown trees, they will be thick at first. Over the years, shady applications will take their toll and they will thin out somewhat.  Slow growth is the second symptom. As I stated above, shade to one side will not cause thinning, lack of straight overhead sunlight is the problem.

Providing light by pruning the offending shade trees is a great idea! If you cut limbs off an evergreen tree that is shading your Leyland Cypress row, those limbs will not grow back so it should be a one-time effort. If you have arborists trim deciduous trees like Oaks, Maples, etc it is more likely to require trimming again at a later date. If the trimming on deciduous trees are cut all the back to the trunk, on the side that shades your Thuja Green Giants you may solve it completely. The advice here is do the tree surgery above before you plant the privacy screen row below. The arborist will probably be able to let the limbs fall if it is done before planting the Leyland Cypress row, while if you wait till after planting, the arborist will likely have to rope the limbs down to prevent damage on your privacy screen below.

Consider substituting Nellie Stevens Hollies for shady applications. Also remember, if you are planting in an established wooded area, the trees nearby not only rob sunlight but will have established root systems that will compete with your new plants for  moisture.   

SPACING

Leyland Cypress spacing.

HEIGTH determines spacing.

David says the FIRST question is how tall do you need them to grow? If a 14’ row of Leyland Cypress or Thuja Green Giant will provide the privacy screen you need, you should be sure and “TOP” them at that height. To do that, you must let them grow a foot or so taller than the desired height, then just clip off the central leader, or main trunk. They should be finished growing tall, and spend their energy thickening out. More height above what you need is a disadvantage for several reasons: The first is that during stress times, like a drought summer, or winter, the tree has to “decide” whether to send the moisture it does have to the upper limbs and truck or the lower limbs, it will always send the moisture to the top growth areas and starve out the lower limbs. Sometimes customers have a row of privacy trees that were doing well, then the began browning on the lower needles. This is because the height reached the point relative to spacing which produced the stress.

RULE of fours.

David Watterson recommends spacing the trees so the target height needed is no more than 4 times the distance between the trunks. If you need a 20’ tall row to block your neighbor’s house or windows, you could space as close as 5’ on center. That is provided you will follow through, and when they reach 21 or 22’ tall, top them back to 20’ height. That means each tree will get the moisture from a 5’ diameter ground area without competition from the tree beside it. It also means there will be enough room for a strong 5’ diameter root system to to secure a 20’ tall tree against the wind.

ZIG ZAG pattern.

David Watterson recommends this solution if you can surrender some “width” of your property for the privacy screen. Let’s take an example; someone needs a 30’ tall privacy screen. If they use the rule of 4’s, and plant a single file row, they should space at 8’ on center, 4 times 8 = 32. If they are choosing to start with ten’ Leyland Cypress or Thuja Green Giant, they will be 4’ wide. That will leave you with 4’ of air in between each tree and waiting a long time to close together. If you plant two parallel rows, with each at 8’ on center, but staggered so that there APPEARS to be a tree every 4’ you will have closure much quicker, yet still have the trees spaced for strength and low stress. In this case the first row should be 4’ from the property line, and the second row should be 8’ from the first. If tight on space, you could make the second row 6’ back from the first row. One note is that the appearance of a tree every 4’ is only when you are exactly perpendicular to the row. Also remember a ten foot Leyland Cypress or Thuja Green Giant may be 4 foot wide at it’s widest point, but also they get skinnier as they get tall.  In this situation, you still need the 8’ spacing based on the rule of fours, and the zig zag pattern will get you closure much sooner than a straight line row, but if you decided on 12 foot trees, they would be 5’ wide at the widest point and you would have your results sooner.

Leyland Cypress Arborvitae Planting and Staking Methods

Select the Proper Tree Stakes

Your choice of tree stakes is partly dependent on what size
trees you plant and the variety. I don't think any tree
catches the wind like a Leyland Cypress! I know some
landscapers feel like it could keep the tree from becoming
strong if you stake them. I have come back 1 week later to
look at trees we planted and the homeowner had already let
the family gardener remove my stakes so the trees would
become stronger! I disagree. A newly planted tree will not
be perfectly rooted when the first winter comes, and the
weight of ice and snow will probably pull it over 30 degrees
or so.  If you are not watching and straightening them up,
they will attach roots in that position and you have to
really harm the root system to straighten up the tree. Even
if you have a Ball and Burlap (B&B) tree with a heavy root
ball and you feel there is no way the root ball will shift,
the wind blowing the trunk back and forth will break the
trunk loose in the root ball and the tree will die. If it is
a Leyland Cypress, it will "wilt" or "droop" within about
two weeks, and the damage is done.

Six foot metal fence posts are the best choice for ten or
twelve foot Leyland Cypress trees. Leyland Cypress trees are
top-heavy, and catch the wind like a sail! I like the metal
fence posts called TEE-posts. The average price is $3.39
each. If you don’t already have one, purchase a fence post
driver wherever you buy your posts. They cost about $16-$19.
 Using this tool makes driving the posts easier and could
prevent metal chips from striking your face. 

Rebar tree stakes are recommended for very hard ground. I
have planted in rocky ground where you couldn’t drive a
metal fencepost in the ground, but you can always drive 3/8"
rebar with a 2 lb hammer. Buy them already cut to 2' lengths
at Lowe’s or Home depot for 99 cents each. After your trees
are all tied, slip a piece of garden hose over the re-bar,
and cut the hose off about 4" longer than the rebar. This
will prevent injury if someone falls on the tree stake.  

Staking with 2" X 2" pointed stakes is recommended for
deciduous trees, even if they are ten footers that weighs
500 lbs. These trees are fine with the 5' stakes, especially if the hole is tight like it should be, because these trees won’t hold the wind like an evergreen tree will. This size tree stake is also fine for smaller Leyland Cypress and Arborvitae trees, 6' or
smaller. A good place to buy is an equipment rental place.
The stakes come in bundles of 12 and can be loaded on your
truck with a forklift. They can also be found at Home Depot
or Lowe’s.

Positioning tree stakes - Leyland Cypress are
usually planted in a straight row or a zigzag pattern. For a
straight row, drive your stakes in line with the outer
perimeter of greenery, and in between the tree trunks. Each
tree will be secured in four directions, tying to two stakes
"in front" of the line of trees, and two stakes "in back" of
the line. The "end" tree only gets tied three directions in
a "Y" formation, because on the end of the row you won't put
two stakes, just one which is in line with the tree trunks.
Using the above technique, all trees are tied in 4
directions, except the end trees are tied in 3, and it only
costs you 2 stakes per the number of trees you planted.
Leyland Cypress or Arborvitae need to be staked at least
three directions because they are top heavy and catch wind. 
 

Securing the trees and stakes - For large trees eight foot
and taller,  use aluminum electric fence wire. Push it
through an 18" piece of garden hose where it wraps around
the trunk. Never secure tree stakes to just a limb; always
wrap around the trunk. If it is not convenient for you to
pick up electric fence wire or you just don't want to pay
for that size roll, you can use rebar wire. It is available
at every Lowe’s or Home Depot near the concrete in small
rolls the size of a doughnut for about $4. The disadvantage
of rebar wire is it will rust and sometimes is rusty when
you buy it. For smaller trees, 6' and under, use any type
of nylon rope.  I use something called pro-series 550/2t
tying twine, made by CWC and available at A.M. Leonard
internet sales delivered to your door. It will disintegrate
out in the weather after about 1 season which is as long as
you need smaller trees to be staked.  I leave the stakes and
ties in the ground through the first winter for larger
trees, sometimes 1 full year.

Leyland Cypress in Shade

Leylands Cypress in shade. Cut out some trees or Limbs if directly overhead to let in more light. Leylands seem uneffected by a row of tall trees or woods along side of them. They grow slower if under a canopy of shade, though, even if the canopy is "way up there" and there seems to be alot of morning or afternoon sun coming in from the side. They will live under a canopy, but not grow fast. I have been hapily surprized at how well Leylands do on Long Island under scrub oaks. It may be because they shed thier leaves about a month before decidious trees in the south do, and grow leaves again in the spring about a month after trees in the south, so all winter they get full sun.

Fall Planting Considerations

Our standard advice is to not plant Leylands after Oct 15, if you are located in VA or north of there. We are primarily talking about Ball and Burlap trees (which is our best seller) since they need to recover from having their roots cut when dug. It is not as risky to plant container grown Leyland Cypress or Thuja Green Giants, of course because their root system has not been wounded in any way. We just planted 147 six foot Leylands in Richmond, VA on Jan 9 and 10 this year(2009).

When you plant Leyland Cypress or Thuja Green Giant in late fall, use Triple Phos fertilizer, usually 0-45-0 or 0-46-0 to encourage root growth only until spring. You don't want high nitrogen in late winter. If you are fertilizing other than late fall, a good schedule is last week of March and first week of September, either 14-14-14 slow release in 40 lb bags from LESCO or Nursery Special slow release in 50 lb bags. Use 1 lb per inch of truck diameter. For 12' trees, a 40 lb bag does about 10 or 12 trees, sprinkled around the drip line. If you are planting B&B trees, don't apply slow release down in the hole like I did for many years. It is meant to be top dressing, will dissolve too fast if in contact with that much more water than on top. Good slow release can feed for 4 months if applied correctly. For Leyland Cypress or Thuja Green Giants, I don't recommend Holly Tone even though it is made for evergreens.

Best time to plant Leyland Cypress B&B trees is early spring, around April 1. This gives them sufficient time to recover before their first test, being the hot summer. However, the biggest test is the first winter. I say that because if you live far enough north to have frozen hoses, all watering usually stops with the first freeze. The cold isn't the test, the lack of water is the test. It is called winter burn. Winter winds dry out the greenery on Leyland Cypress or Thuja Green Giant, so the outer few inches turn brown. Around April 1, it is recommended that you take hedge trimmers and trim off all the brown. Trees should put out new growth and be fine by the end of May.

 We are still shipping Leyland Cypress, Thuja Green Giant during the summer. We water them well, and have our drivers travel at night so the trees arrive cool and wet. If you have a 2,500 minimum order, email us or call 240-498-8054

You should order from Watterson tree farm because:

1. We provide all the questions/answers as any retail nursery but deliver wholesale prices.
2. We can help you decide which trees are best, what is the best spacing, time to plant, etc.
3. We don’t just have great inventory, we also have great trucking arrangements and know how to pack a truck so you trees arrive on-time with no damage. We specialize in Long Island orders. 

If you have a $2500 minimum order, Call 240-498-8054 anytime and  weekends ok