Japanese Knotweed - When to treat?

Buztafen

Morning all and Happy Easter.

I have an area of Knotweed on land i own at the back of my house (approx 24m2, 6mx4m) which i am in the process of treating. Over the winter i cut back and burnt the dead stems in situ so the area would be ready for herbicide.

After reading various information packs the best time to treat the area is in late summer, however it is mentioned that treatment can commence around April/May but it may have less of an effect.

Basically i'm wondering if there's any benefit in spraying the Knotweed now, or should i leaving it till late summer and not waste the rather expensive herbicide?

Does anyone have any experience in this area?

Many thanks.

Scotchnan

Is it growing? Spray it.

walkers-crisps_are_evil

This plant is a nightmare and you need to do the job right. Hence I provide this link rather than give you advice as it's best coming from the horses mouth...
http://www.environment-agency.gov.uk/homeandleisure/wildlife/130079.aspx#How_to_control_Japanese_knotweed

The company I work for are dealing with an outbreak on an estate. We dug it up last year to break up the rhizomes and burnt the plant rhizomes and foliage when dry. This year it's spraying with glyphosate weed killer to finally kill it off. Effective when there is foliage to take in the poison. Repeated applications necessary.

Smithills

I too have the delightful Japanese Knotweed- not in the garden, but in my woods (which sound very grand, but it's just a strip down to the river!).

Over the past 5 years, I've gone down there 2 or 3 times during the season and cut and stacked it to allow it to dry out before setting fire to it. You need to stack it where it falls so you don't transport it anywhere. I wait until it's perhaps 2 or 3 foot tall just so it's easier to see. This has weakened it year on year, and then last year we found out that my neighbours chickens like to eat the leaves! So we just stack the central stems that they don't eat.

I don't spray it- the slope can be a bit precarious, but I would suggest that you give the stems a bit of a bash before you spray- just so your expensive herbicide gets right in to the growth, rather than running off the leaves. I think that you could add a splash of washing up liquid to improve wetting- though that's just something I've heard of to improve the performance of other sprayed-on garden chemicals and not something I've tried.

I think that whatever you do, you won't get it first time, but if you are persistent, you will get on top of it. Good Luck