We planted several leyland trees 3 1/2 years ago. Wanted them for privacy and to create a shrub/wall with them. We were told to plant 5 ft. Apart. We have 10. We unfortunately did not trim like we should have. My question is, is it too laye to create the shrub/wall with them. Do we need to start over? They are approx. 12 ft tall. We just trimmed them quite a bit. Probably 2 ft off the top and massively everywhere else. Thanks in advance for any help.
Thank you for your question about your Leyland cypress. These probably aren't the worst plants to have for a low hedge, but they're right at the top of the list. Their mature size is 70 feet! These are probably the epitome of "the right plant in the wrong place is the wrong plant."
Although you can prune them, eventually they're going to get away from you (or a subsequent owner of your house), and then they're going to be very difficult to remove, let alone prune. Here is an excerpt from an Extension article about this tree:
"This is a fast-growing evergreen when young and will quickly outgrow its space in small landscapes. It is an excellent choice for quick screens, hedges and groupings, especially on large properties. This tree tolerates severe trimming, and can be restrained at an early age with pruning. Although Leyland cypress can be sheared into a tall screen on small lots, it is most effective when allowed to develop into its natural shape. Regular trimming is necessary to retain a formal hedge, screen or windbreak. When considering this tree for use in a design, be mindful of its projected height. It usually grows larger than most people desire. It is a good background plant, and contrasts well with broadleaf evergreens.
This tree prefers sun to part shade and well-drained fertile soil. It is very adaptable, however, and tolerates acidic or alkaline soils and poor drainage on occasion. It withstands salt spray and is suited for coastal landscapes. Prune only during dry periods to help prevent disease."
Here is a short article explaining how to prune them. It sounds as though you might want to hire a professional to do this, unless you love climbing on wobbly ladders. Hope this is helpful. Good luck!