I’m in Portland, OR (zone 8b and love my leyland cypress). We have a variety available here, Island Green, which reaches 20’ tall and 6-8’ wide. Monrovia offers a similar tree called Emerald Isle. These are quite manageable and a pretty screen behind layers of golden ash trees, camellias, and rhododendrons. I also have traditional leylands that I keep in the corner of a planting bed where they only have about 9’ of space. They do just fine and I limb them up and have hydrangeas growing below. The hydrangeas are happy here. The leylands get full sun and receive a lot of wind at the top of our hill. I’ve never had to clean up a broken branch. They get a ton of water because it rains consistently here Oct-May. Winters can get down to 25F, but snow is infrequent. None of them have grown more than 1’ each year in height. Surprisingly mine have put on more width at the top than the bottom, which I’m happy about. These cypress trees and my boxwoods are the easiest plants I have (although nearly everything grows well in my area). They might not be great everywhere but I definitely like them better than my arborvitae. The arborvitae get brown patches, grow slowly, and are narrow at the top. I like my Bay Laurel hedge as well but they grow much more slowly and require more effort and watering. I hope these comments help!

There's no way on this plantent, where you live, that Holmstrup will winter burn. Some idiot wrote that. Snow loads, nah, that's wrong too. That's a fine cultivar for what you're doing. Perfect for your space requirements - can be brought into practitically any nursery on earth at a 6 foot height, the list just goes on and on. Degroot's Spire - the same holds true for. Although, now you're looking at paying the bigger bucks. What I imagine for your purpose is a Holmstrup planted every 24".. Ken's suggestion of 18" for Degroot's seems good there, for that cultivar. Pruning: cut em flat across the top and walk away. It's that simple. Anything else and you're creating more work for yourself in the end. Hetz Wintergreen aka Wintergreen is now encroaching into that plant that after time will require that you maintain the entire plant, meaning, your ladder ain't gonna fit very well into that spot. Then... it just grows too fast. Wrong plant. Don't even consider Woodwardii either. Hell that's 10x the wrong plant. You want height not width. If it were possible to find larger plants: Malonyana and/or Malonyana Aurea would be welcome to that site. These selections are all pillars, which is an important concept in your design. They grow vertically and not (very much at all), horizontally. I've seen a 30 foot tall hedge in zone 4a in Iowa of Holmstrup and it was outstanding. I was on a garden tour this summer. Dax

God i hate when i forget the link ... you asked my opinion ... i gave it ... 85 degrees is NEVER a good time to plant ... holding them a week or two ... in shade... will probably mean... temps in the 70s ... and cooler at night ... just less transplant stress... and a little time to get over shipping stress .... take a drive thru your greater area... how many of the HUGE trees do you see... that were NOT amended at planting ... and a vast majority of them probably self seeded [i am not talking suburbia here] ... in native soil ... there is nothing inherently wrong with clay ... the problem is... us.. transplanting improperly into clay.. and then killing them thru improper watering or amending.. or fert'g ... etc ... we add all the variables on transplant.. and then wonder why ma nature fails.. she doesnt.. we do .... the idea that these are some kind of babies which requires coddling.. is nonsense .. and its when we start coddling them ... that we add all kinds of variables.. that simply complicate the whole deal ... if you amend a hole.. in bad clay.. ts possible ..... the tree.. will simply wind its root around.. and around.. and around.. in the amended soil ... if you plant in native soil... they are forced to deal with it ... and with proper planting.. and watering.. they can deal with it ... and not being babies.. they will most likely never need to be fed.. nor diapered.. nor educated ... etc ... treat them like the trees they are .... plant them like trees plant themselves.. and you will be well on your way.. to growing a plant.. that can deal with your native conditions.... of which.. i am presuming GGs are ???? and... if they are within feet of a fertilized lawn .... soon enough.. will will have roots out there.. stealing anything they may need ... just like painting.. prep is 95% of the job .... now that you have your plants.. you have the other 95% to do ... remove 3 inches of sod ..... dig a hole... and plant tree according to the link above ... high in bad clay ... and water properly .. BTW.. have you ever perked you soil???? ... perhaps your clay isnt as bad as you think... dig a hole .. fill it with water.. and find out.. how long it takes to drain .... then plant accordingly ... we like this planting guide.. because it is written by one of our own .. though most peeps dont admit they know brandon.. lol .... and it encapsulates what we all believe... its not worth this very col typing.. to have an exoteric discussion on all the other website you have seen ... this whole amendment thing.. started by nursery sales peeps.. wanting to increase their profit.. by selling you not only the tree... but all the high profit amendments.... its like the car dealer wanting to sell you undercoating.. warranties... etc ... why do we tell them no.. but cant help ourselves with our baby trees ... dont complicate your life ... ken

my worry would be that if the soil is staying saturated, you're causing root problems for all the trees. Unless you want to be cycling through replacements, I'd fix the underlying problem the right way - which is getting the water out of there. One of our winery clients was having massive water problems in a few of their vineyard blocks, to the point where you could grab a vine and pull it right out of the ground - the roots were all rotted. Their consultant had them run french drains between the rows and they're now producing literally tons per acre. It works.