In addition to it not necessarily really being possible to achieve a 35 ft. x 5 ft. hedge that is not pruned to remain narrow it may not be necessary to have the screen grow as tall as the houses in order to get adequate relief. And such a planting is not going to produce the desired effect overnight. Even with a choice that managed to average 2 ft. per year of height increase (after full establishment) there is going to be a more than 17 year wait before 35 ft. in height is attained. At which point the planting will itself be looming over your lot, to produce the same feeling of being walled in that the new houses are now. To appear in scale with a space a planting needs to be about 1 1/2 times in height as the bed is wide. So a 5 ft. wide bed should have a ~7ft. tall planting for everything to appear in proportion. A 35 ft. tall planting in a 5 ft. wide bed is about 5 times taller than is desirable where a completely comfortable psychological effect is to be produced. I believe this commonly shared feeling that trees and shrubs are "too tall" when confined within spaces that are not wide enough to house them visually results in many specimens and plantings being brutalized and spoiled by topping. This post was edited by bboy on Sat, Sep 27, 14 at 11:13

It comes from parts of the PNW that are dry in summer - Sequim Washington has only 14" of rain a year in winter too, but is of course much cooler than you year-round. So it's not particularly remarkable that they soldier on for you. In Barcelona, Spain, for example, which is summer dry though not quite so much as California, there are huge unwatered hedges of the Asian summon-monsoon loving Pittosporum tobira. Now that's a surprise. Someone from California will know for sure but I think after 3 years of stingy watering it should be able to fend for itself. You don't want to indulge it. Just water it enough in summer to keep it from dying. This post was edited by davidrt28 on Wed, Jan 23, 13 at 17:31

at the link below.. suggested growth rate is 2 to 5 feet per year ... you meant the green giants.. yes?? why would you presume that Britain would have a slower growth rate ..??? ken Here is a link that might be useful: link

Thank you Tom, Yes, I am looking for the chamaecyparis p. now to mix with plicatas (and maybe hemlock). Can you recommend any nice TALLER chamaecyparis p. cultivars? everything I am finding would only get 2-3 or 3-4 feet high tops, and my chain link is 5 ft tall and I would love to be able to hide it!! So, in summary, my plan for today is the following for the ~300 ft border. There are 3 sections of it, the further West ~50 feet sometimes damp but part sunny (which is not visible from the house because of 2 ~20 ft Norways are blocking the view). I want something narrow there because I started an orchard there, so I may do the HW bare root, nothing else and I will see if deer attack those. Then I have ~200 feet section which is mixed, part sunny and some areas get damp and shady, so this is my main concern, this section I see from various parts of the house. I would like to plant a natural looking hedge (Dax's influence). But now you got me thinking again, should I try to mix in picea abies cupressina with the plicatas and chamaecyparis p.? The old norways which are planted in the sunnier area are doing extremely well in that area... Then at the end (of the 300ft border), I have a sunny but swampy wet area of ~50 feet in which area I only care that it is green and tall to block the view of the private road and the main road visible in the distance. So, I just need to do a background green. I do not plan on cutting/shearing trees there. So, for this section I am still not completelely decided... maybe GG or plicatas straight species but worried about the size being too wide and taking too much space. I have a question for a different spot in my yard, adjusent to this swampy area, but this is ~20 feet of swampy wet, often standing water and mostly deep shade, what do you think, would chamaecyparis nootkatensis pendula w/metasequoias or taxodium distichum be an option for there?