I decided to create a separate page for the Japanese Knotweed as I'm accumulating a lot of photos of it, having observed 5 occurences of it near me. I like to keep an eye on any Japanese knotweed I see - how fast it grows, does it get invasive, is it flowering?
October 2024
I saw this Japanese knotweed in a front garden. In bloom, they seem to floweer pretty late in the season.
view of the entire plant
End of October 2018, I went over to Regent's Park to check on one I saw last winter, which wasn't flowering at that time but it was flowering today. My first photos of Japanese knotweed flowers and buds.
It was only when updating my blog here, I see the photos above and below are so similar. Not sure which is better.
spray of buds there on the left
November 10 2018
This is the largest most established example I've seen, near the example above, I only discovered a few days ago so not sure how long it's been in bloom.
the flowers spikes are growing straight up
close-up of some flowers, these are past their prime and I can see the seedhead forming in the centre of the flower, although I've heard knotweed doesn't spread by seed so does it produce seeds?
this, like so many plants I see, has reddish tinge and I don't think that's the plant, I think that's the environment, especially as I've seen other reddish plants nearby
this is another Japanese knotweed plant but it's smaller and younger and not in bloom
another plant nearby
May 2018,unlike other small suspected examples I've seen, this Japanese Knotweed is tall. It has a speckled stem with nodes and shield-shaped alternate leaves.
close-up of the stem
another shoot near the tall plant above, I will go back and measure the leaves
Oct 2018 and that Japanese knotweed is in bud.
this branch doesn't have any buds
November 2017
The first example I noticed as a small shrub along the railings of the London Zoo car park and thought it looked familiar. I don't know why it's a sprawling shrub rather than tall stems.
I did wonder why such an isolated shrub? so a couple days later I went back and looked further and found 2 more along the railings but still no huge patch of it as you hear horror stories of.
this is a wider view of the environment, the first example of the Japanese knotweed is at the base of the lamp post on the far side
the Japanese knotweed is on the right below along the railways, quite far from any gardens across the road
the smallest Japanese knotweed I've seen, small shoot in a front garden round the corner, April 2018
that was cut down to the ground but it's back (Nov 2018)! with a few shoots rather than 1 but still reasonably slow-growing
a small Japanese knotweed nearby, inside a hedge, only noticeable on close observation Oct 2019
another very small plant, Oct 2019
October 2019, Because there was some Japanese knotweed on the property next door to this one (since cut down) I looked in this front garden and saw two, well-defined, small-ish Japanese knotweed shrubs. They do not appear invasive.