Finally got there. 3 loose ends for me
Why is the food at the end of 18 (other than to make the message work), I have a US chemical used in fertiliser which seems quite a long way from food. Is that it or is it used in food as well (or do I have the wrong answer)?
5d - is bond meaning bed? Not really seeing that?
1d - have a French word related to garcon but can't see the wordplay at all.
Thanks