What is this weed & how do I kill it?

[peter]

Prostrate creeping purple leaves with yellow flowers.
Reminiscent of trefoil.
When dug up it has a 2 to 3 inch taproot with a circle of roots at the end. Then looks like uprooted palm trees roped together at the top.
It throws out on the surface like buttercup.

Only in my greenhouse border and long term pot plants.

[Parsons Jack]

Hi Peter,

Try this one. Very pretty, but very invasive

http://apps.rhs.org.uk/advicesearch/pro ... px?pid=498

[peter]

T'internet is so reliant on one knowing the name of something to start with.

Yes dats der bunny.

[Beryl]

I've been plagued with this one to for the last 3-4 years.
Glysophate does help in the short term but its another one of those, leave a bit in and its away again. Constant weeding and don't let it flower if you can.

Best of luck]
Beryl.

[Johnboy]

Hi Peter,
I am not familiar with this particular variety but is it one that not only seeds but also produces bulbils and is rhizomatic.
This seems to act similarly to Lesser Celandine which was a great problem here at one time. If you could manage to pull the plant out you generally left the seed and the bulbils, unseen mostly, to regenerate with a vengeance.
I got rid of L.Celandine with the application of 2" layer of sharp sand over the top of the plants forcing the new plants to grow into the sand and then when growing away well you remove the complete layer of sand with plants, seeds and bulbils in one fowl swoop!
Now you may be able to adapt this method in some way to get rid of Oxalis but this is only in theory. Perhaps this may be totally impractical but it gives you an idea as to how to treat some weeds that become really invasive without having to resort to weedkillers.
JB.

[Beryl]

If its the one I am dealing with it has long trailing fine roots. not very deep though. Grows between cracks in paving which unless you lift the paving almost impossible to get it all out.

Beryl.

[Johnboy]

Hi Beryl,
Try the sand method on a small patch and see how you go. If you can coerce the plant out of the crack and with a shallow root simply wait until the plant is established in the sand but not flowering and pull it out. Give it a whorl in a place that will not interrupt your day to day walking and you may be pleasantly surprised.
I find that it is the simple things, that we as gardeners, miss.
JB.

[Beryl]

Yes I will JB
Thanks
Beryl.

[Primrose]

If it IS oxalis, I fear you will have a long battle. We've had it in our garden for 30 years and I still haven't succeeded in eradicating it. The tiniest little bit of root or attachment left in the soil will just start regenerating again. I try to dig mine out on a dry day when the soil is at its lightest so there is as little stress as possible on the roots and get as much of the root ball out as possible. I also try to do all my oxalis weeding at a separate time, keep the weeds in a container and put them in the dustbin. If you put just one little nodule on your compost heap the darned stuff will regenerate start the process all over again.

We also seem to have another version of this in our garden and it's equally deadly in terms of spreading.

[Beryl]

Is yours the one with reddish leaves and yellow flowers Primrose? if so I don't think there is much hope for me.

Beryl.

[Primrose]

I've got that one, but the other similar one has just green leaves and that seems to be worse. I find the one with the reddish leaves & yellow flowers is a lot easier to dig out intact as it often seems to have a bigger main globule type root. The green variety is generally smaller and has much nastier and more malignent nodules on its roots.

I find that I can have a really thorough blitz on a particular border and rid it of every single visible weed of that type, but within a fortnight in the growing season, new plants are already growing through again..

I don't remember seeing it in the garden when we first moved here when it was a brand new house and garden. I obviously bought in a number of shrubs, etc. in pots and I suspect there may have been some of these weeds in the pots which have subsequently spread it throughout the garden as perhaps I didn't realise their malignency and originally threw them onto the compost heap with all the other weeds. I know better now !

The other weed root to avoid putting onto your compost heap is Alkanet. It's a big green leafy plant with small blue flowers and in its early stages the leaves look very much like foxglove leaves, although the Alkanet leaves have small silverish spots on them. I do compost the leaves but not the incredibly long tap root, as that seems to be able to regenerate itself at will and is the very devil to get rid of.

I have myself to blame for the spread of that one too. I transplanted a lot of these young plants around the garden thinking I was transplanting young foxgloves which would provide me with a colourful show later in the year. And now the darned plants keep appearing everywhere!

[Johnboy]

Hi Beryl and Primrose,
What you do not seem to have grasped is that by using a layer of sharp sand you are moving the plant onto a new layer, the sand, which is totally dispensable.
My Lesser Celandine had been getting worse for twenty years and I got rid of 95% in the first year and didn't get 100% because I was a bit mean with the sand in places. The following year it was simply a mopping up exercise. I still have LC in the hedgerows because as a flower it is, to me,
very beautiful but not in my shrubbery! BTW my shrubbery is about an eighth of an acre.
JB.

[pongeroon]

Thats a useful tip for me JB, as I have celandine creeping under the fence from next door. I ususally manage to get some out, but there are always a few bulbils lurking underground. they are lovely little critters in the right place , though, as you say.

[Johnboy]

Hi Pongeroon,
I try to help where possible.
I have chosen a new route through Worcester and I pass an allotment going this way and always wonder if you are a holder there. Think me foolish but I always wave just in case!
JB.

[Elaine]

I have had this little monster in my back garden since we had the floods in 2007. It grows very rapidly in between the pavers on the patio and has even managed to get into the buckets we grow our strawberries in...and they are up on trestles, not on the ground!
I had some success with Roundup last year and will be zapping 'em again this spring. (not in the strawberry buckets of course)
Cheers.