...oh that's an easy one we can all answer, in unison perhaps...?
Rape ! to make rapeseed oil...
It's a brassica, same family as cabbages, kale, Brussels sprouts etc http://en.wikipedia.org/wiki/Cruciferous_vegetables
It needs lots of bees to pollinate it - nowadays farmers pay beekeepers to place their hives near their fields of rape.
I call them sunshine fields because they always look so sunny and bright.
I call them snot fields because they set off my hay fever. But they are a cheerfull sight.
The smell overwealms some of the more pleasant scents from the garden. Nice yellow though
I once saw a pair of crows, totally overcome by the smell or the strength of the pollen or something, on a narrow country road between two very large areas of flowering rape at midday on a very hot sunny day - they behaved as if they were drunk, unable to fly more than a couple of feet at a time. I watched them for ages.
Oil seed Rape- it dont half stink after its rained! it can be exused though with the cheerful yellow of it!
The Blue is better that is the Linseed Oil /flax I think ?
The blue is lovely. We had a white version in a nearby field one year. Not half as nice