Vegetarian Fertiliser-is there such a thing?

[Kristen]

I have used it, and it doesn't work

I agree with many of the points you made. Repeat spraying on persistent weeds is likely to be necessary to get a good kill. However, I think used before rotavating will mean that the bits of chopped up root are more likely to struggle to regrow because of the effects of the chemical on small pieces. I agree that rotavating is best avoided if the ground can be prepared by some other means, and any allotment that has been in existence for ages is likely to have soil that is in good heart and can easily be got round - virgin heavy-clay agricultural land would not be so easy

It does kill worms and amphibians though.

That's no longer the case for the new formulations of Monsanto's Roundup. Previously the Adjuvants (e.g. Surfactants to make the chemical stick to the leaves, and chemicals to help the Glyphosate active ingredient pass through the cell walls etc) were the toxic part of formulation. That is, presumably, still the case of the generic Glyphosate based weedkillers. The latest formulations of Roundup have better Adjuvants and no longer carry a "hazardous" symbol. In particular they are safe for aquatic wildlife.

Not wishing to promote the use of weedkillers ... just wanted to mention that there appear to have been some improvements. Although having said that I don't know if those improvements have made their way into products for Amateurs as yet.

[Two_Sheds]

I agree with many of the points you made.

The latest formulations of Roundup have better Adjuvants and ... are safe for aquatic wildlife.

That's reassuring to know, thank you.

I like conversations like this one: people giving differing, sometimes opposing, views but everyone is polite & respectful. It's made my morning