Hi @prettypeas
Wow, those are some big conifers! If you haven't already, check out my conifer guide here to learn more about why you can't just hack them back.
I think you've hit upon the same problem as many Lleylandii owners: for many years, their conifers act as a great screen and require little to no pruning as they look 'fine'. However, at some point, they rocket up and become overwhelmingly difficult to prune and manage. This is why they really shouldn't be sold at nurseries (B&Q) unless they are being bought by arborists who can manage them! No shade, but my warning is that they tend to take over, leaving people like you with the right problem.
But what are your choices so we can find a solution?
1- Cut them back to the ground and have the stumps ground out.
Probably not the best option as you will lose all the privacy, and local wildlife will have its home decimated. Also, the stumps will stay in the ground forever (well, nearly), leaving dry, dusty earth that's impossible to work with.
2- Cut the tops off
You could do this to 'top them out' and stop them growing; however, looking out of the house, you will be left with an exposed, awkward wooden core of the tree forever more.
3 - Crown lift the trees and prune them each year carefully
Probably the best option, but most time-consuming, is to crown lift the trees (or get an arborist to do this) and then get them each year to properly prune them to manage their size. They do this in chunks rather than cutting back conifers to old wood stoops for any future growth and exposed brown dusty stems, which you don't want. This is why you need a trained arborist with qualifications not just man/woman with a harness and a chainsaw.
I know neither of those options provides an ultimate fix but at least you know what you're up against, not impossible but certainly something to think about.
Do let us know how you get on!
Lee Garden Ninja
Hi @prettypeas
Wow, those are some big conifers! If you haven't already, check out my conifer guide here to learn more about why you can't just hack them back.
I think you've hit upon the same problem as many Lleylandii owners: for many years, their conifers act as a great screen and require little to no pruning as they look 'fine'. However, at some point, they rocket up and become overwhelmingly difficult to prune and manage. This is why they really shouldn't be sold at nurseries (B&Q) unless they are being bought by arborists who can manage them! No shade, but my warning is that they tend to take over, leaving people like you with the right problem.
But what are your choices so we can find a solution?
1- Cut them back to the ground and have the stumps ground out.
Probably not the best option as you will lose all the privacy, and local wildlife will have its home decimated. Also, the stumps will stay in the ground forever (well, nearly), leaving dry, dusty earth that's impossible to work with.
2- Cut the tops off
You could do this to 'top them out' and stop them growing; however, looking out of the house, you will be left with an exposed, awkward wooden core of the tree forever more.
3 - Crown lift the trees and prune them each year carefully
Probably the best option, but most time-consuming, is to crown lift the trees (or get an arborist to do this) and then get them each year to properly prune them to manage their size. They do this in chunks rather than cutting back conifers to old wood stoops for any future growth and exposed brown dusty stems, which you don't want. This is why you need a trained arborist with qualifications not just man/woman with a harness and a chainsaw.
I know neither of those options provides an ultimate fix but at least you know what you're up against, not impossible but certainly something to think about.
Do let us know how you get on!
Lee Garden Ninja
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