21may weed killer found in compost hero
7 May 2021

Weed killer found in compost

Compost pulled from sale after our testing finds it contains weed killer.

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John J.
11 May 2021
Compost & clopyralid

Under the heading 'Who's testing' It's interesting that just 14 of 33 replied to your question. Of the big 3 mentioned, I like Yates approach that it tests from each row of prepared compost.

Robert H.
10 May 2021

I have had a contaminated Garden Mix which twisted up my Magnolia seedlings. i have not had it tested to prove it was Clopyralid, but the description of what happens to the plants is the same. To use Clopyralid you need to be an "approved handler" so this means it is either being used illegally by a home gardener or an irresponsible approved handler. Hopefully the Magnolias will grow out of it next season if put in a clean mix.

Hamish W.
09 May 2021
What about glyphosate

Does using round-up have similar effects?
We suspect it does :(

Robert H.
10 May 2021

Glyphosate is supposed to break down in soil. If you use dirty water for instance to make up your spray mix, you may render the spray useless. However I have heard reports that Proteas growing in glyphosate sprayed soils do not do well, indicating it may accumulate. Spray drift is something to watch for. Even a few drops can yellow a plant and if you ever use a marker dye in your spray, you will be surprised how far those little droplets go.

Nick d.
08 May 2021
Pea Straw too!

We got several bales of Pea straw from a Waikato supplier and used it as a garden mulch. It stopped weeds germinating but also any vegetable seeds we planted.
The supplier denied all knowledge of spray use but I suspect a "pre-emergent" spray was used on the pea crop. We removed all traces of the straw but the garden has taken several years to recover and still won't germinate seeds in some places.

Dinah D.
08 May 2021
2019/2020 summer tomato crop ruined

I wish I had known about this sooner. We bought a trailer load of 50/50 compost soil mix from Nichols in Dunedin in October 2019 for my tomato crop. All plants had deformed leaves and fruit (what little there was). I concluded that is must have been the compost or soil but never thought to get it tested.

Barbara L.
08 May 2021
Potting mix not all organic

That was such a helpful article about compost. I had M10 garden section ring the supplier about their organic potting mix to find it has saturaid in it. Best compost and potting mix is what you make yourself.