I live 18 inches from my neighbour and want to block out his wall. I have looked at numerous evergreen trees but need an expert’s advice. The tree should be of very narrow width, columnar not pyramidal, fast growing, sun and shade, and ideally 25 ft tall. Any advice ?
Thank you for contacting the Toronto Master Gardeners. As you probably know from your research, there aren’t many evergreens that meet these specific requirements. It is important to have full knowledge of your growing conditions before choosing your tree. I’m not sure whether you have full sun (at least 6 hours of direct sun daily) or full sun-partial shade (4-6 hours of sun daily, usually not in the heat of noon and the afternoon). Many evergreens require full sun to thrive. Typical soil requirements for these trees are moist and well-drained. Some evergreens are adaptable, however compacted soil or soil that is waterlogged and has the plant standing in water likely won’t work well. Other considerations are soil pH and exposure to wind, especially in the winter.
You might want to consider a couple of weeping Alaska cedars. These trees grow to 20’ tall and are 1’-2’ wide, with a moderate growth rate. They require full sun and soil that is consistently moist but not waterlogged. Vanden Akker Alaska Cedar (Chamaecyparis nootakatensis ‘Vanden Akker’) grows to just 1’ wide, and Green Arrow Alaska Cedar (Chamaecyparis nootakatensis ‘Green Arrow’) grows to 2’ wide. Below is a link with more information. Vanden Akker Alaska Cedar is #10 on the list in this link, and then click on ‘all the weeping Alaska cedars’ for information on Green Arrow Alaska Cedar.
Another possibility is Eastern Arborvitae Hetz Wintergreen (Thuja occidentalis ‘Hetz Wintergreen’). It is fast growing to 25’ tall and 6’ wide. It requires full sun and moist, well-drained soil. Here is a link with more information :
Scotch sentinel pine (Pinus sylvestris ‘Fastigiata’) is another option. It is fast growing, to 25’ tall and 8’ wide, and requires full sunlight and moist, very well-drained soil. Here is a link with more information :
You might also want to consider Weeping white spruce (Picea glauca ‘Pendula’). It is fast growing to 20’-40’ tall and 5’-8’ wide. It requires full sun but will tolerate some light shade, and moist, well-drained soil. Here is a link with more information :
Good luck with your search !