Standard trees - will the stem grow taller or only thicker?

[Aridane]

A quick google doesn’t help me so thought I would turn to the collective wisdom here

Thicker. The crown point of the trees in my garden hasn't got any higher in 25 years. If you want to make the "stem" taller you do it by removing the lower branches, and there comes a point when it gets rather difficult because it's no longer putting out vertical branches, just sideways ones. so you can't keep removing them.

Thanks - they were purchased as standards (bay trees, olive and holly trees) - and I just wondered what their growth potential was

The trunks will thicken faster if you allow just one 'sacrificial' branch to grow tall. You leave it several years and then get rid of it.

So why do ‘regular’ trees / plants grow taller but not ‘standards’?

@Aridane

So why do ‘regular’ trees / plants grow taller but not ‘standards’?

Ah - different question! The tree will grow taller, but not the stem. So you may buy a tree with a 6ft stem and an 18 inch ball of branches at the top. Total height 7.5 feet. A few years time, you'll still have a 6 ft stem, but you may have a 4ft ball of branches on the top. Total height 10ft.

In other words, growth is by extending branches upwards, not by stretching the existing trunk.

Holly and bay can get to 50ft.

Oh, I see 💡

Your bog standard tree is genetically programmed to grow tall, and as they grow the lower branches are shaded out and die back, eventually being shed altogether. Standard varieties have had all the lower branches removed when young and have been pruned into a lollipop shape at the top. If you keep pruning the top, it will stay much the same height.