Cutting the top off conifers is a drastic move and you should do it only after careful thought. You need to examine the tree for the best place to make the incision so that the tree continues to grow healthily and strongly. And then make the cut cleanly. Be sure you really want to do this as your action may spoil the shape of the conifer permanently.

Where to cut the top off conifers

Most conifers form new buds at the tips of their branches. Some types, including cypress, hemlock and juniper, also form buds and new foliage in random places throughout the tree. Most conifers don’t grow from old wood, only new buds. So you need to leave the new buds to carry on the growth of the tree.

Select a place on the tree trunk to cut. Make sure that the cut is just above a place to which branches with new foliage or buds are attached. These are the places where the tree will continue its growth – outward rather than upward.

How to cut the top off conifers

Use a pruning saw to cut the tree trunk at your selected place. Pay attention to all the safety precautions necessary for cutting down part of a tree with power tools, especially chainsaws.

You can establish one of the (now) topmost branches as the new crown of the tree. Trim your selected branch to 15cm to 25cm. Bend it upright to be parallel with the tree trunk and hold it in place with a stake and some sort of tie to hold it in an upright position. It will now grow in this position and look like the top of the tree. This preserves the tree’s conical shape a bit.

Warning

Large conifers don’t respond well to having their tops cut off, this is why you sometimes see large conifers that have been pruned back heavily and the shapes never recover. The removal of the top of the trunk leaves the tree open to disease, decay or insects that harm it. They are usually very bare in the centre too. It also removes the part of the tree that develops most. You also lose the iconic cone-shape of the tree as branches at the now-level top start to grow in all directions.

The only time it doesn’t really matter is when you want to hard prune an established conifer hedge, say from 10ft to 6-7ft. You will still have the open bare top but it will probably be above head height so you won’t be able to see it in most cases and the sides with grow as they usually do.

If you have a leylandii, be careful not to prune the sides too hard right back to brown bark, they only regrow from green growth.

If you notice your conifers turning brown, check out my guide here on possible reasons

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