Now here’s the science

Translocated

herbicides have the capacity to enter a plant through its leaves and then travel though the entire plant via its vascular system, which means weedkillers of this nature will kill the plant, roots and all. The following ‘active ingredients’ do this: glyphosate, 2,4-D or MCPA.

Salt

can work as a contact weedkiller but used extensively it will poison the soil making it unsuitable for other, desirable plants.

Horsetails

have been around for well over 100 million years. One of the reasons for this long-term survival is that their roots can penetrate 1.5m into the soil.

Small annual

weeds such as bittercress have an unusually short life cycle, meaning some can go from seed to a flowering plant in 4-6 weeks. Un-checked, their exponential spread in the garden can be huge.

Table vinegar,

although recommended by some organic gardeners, is not really acidic enough to have any marked effect on weeds. Better use one of the new acetic-acid based weedkillers.

Some studies

have claimed that glyphosate (a translocated herbicide) can remain in the soil and be a cause of cancer. Others claim it is perfectly safe. I avoid it where I can.