Ultimate height. I was just wondering if they actually get that big on the East Coast. Or because they are in a row their height might be affected.

look at the bark ... determine how much they grew last year ..

and then multiply that by forever ...

as trees.. they will really.. never stop growing

ken

My neighbor has a GG hedge, full sun, about 6ft apart. The hedge is around 15 years old and 20ft tall. No question, being planted in a row definitely slows their growth rate once they start touching, but either way, he has started rounding/trimming the tops for the last 5 years to keep it from becoming the green monster wall... It's starting to become pretty imposing.

A solo specimen would probably be 30ft+ after 15 and twice as wide as his are. As pointed out, there are examples of 60ft+ Green Giants as the US Arboretum, even some hedges nearing that height, though I don't know the planting distance. GG's do extremely well in the east, other than potentially shorter sunlight hours/intensity, there is nothing on this coast that will slow them down. They are great.

of course the growth rate is highly dependent on location ...

e.g. my MI growing season might be a month or 3 shorter... than those the higher you go with zone ...

ken

Thanks everyone. I have no intention of topping them....a 60 ft tree should be allowed to grow as it was intended. I think they're gorgeous, that's why I planted them. I had just "heard" that 60 ft would be in ideal conditions, and realistically they would get 25-40.

Thanks for the help.

60 ft would be in ideal conditions

==>>>nonsense ... they are trees.. THEY WILL NEVER STOP GROWING... ever...

i know the IDEAL part you are talking about.. and in regard to these.. i seem to think it was about how much it might grow in one season ... in ideal conditions ... which to get to some of those claims they made back in time.. meant a greenhouse.. and year round growth ...

ken

Green Giants are magnificent, I have about 20 planted over the last 10 years. 8 feet apart is too close if you want them to reach their maximum height. Yes staggering them is better because as they keep their conical shape they will start to touch at the bottom first and there will be a gap further up, that can be eliminated by staggering. Keep the grass away from them and they grow faster.