[james-bcn]

> highly invasive and spreads easily

If that were the case you would expect to see large growths of it in the wild, right? Whilst I do see it in the wild, I've never seen any situation where it looks to be taking over. I just see individual plants occasionally.

[rob74]

My reference for "highly invasive and spreads easily" is https://en.wikipedia.org/wiki/Impatiens_glandulifera#Invasiv..., which has by now completely taken over most clear and shady areas in and near forests where I live. Summer lilac is definitely far from being that bad.

(I live in the South of Germany, but the UK, where it was originally introduced in the 19th century, seems to also have a huge problem with it: https://www.cabi.org/invasivespecies/species/himalayan-balsa...)

[james-bcn]

That is not summer lilac. This is:

https://vibrantgardenblog.wordpress.com/2016/12/02/buddleia-...

[pvaldes]

> I've never seen any situation where it looks to be taking over. I just see individual plants occasionally.

Each one of those individual plants can produce 40.000 seeds each year, so give them a decade alone and you will see. Is very invasive on river beds and disturbed soils.

[jibbit]

fwiw the railway verges in london seem to be predominantly this - which also incidentally - i've never heard anyone call Summer Lilac before