Creeping slithering things

I knew that there were grass snakes in Warwickshire but I have been in Devon for more than two years and had spotted no evidence of a slithering thing until now. My composure is therefore ruffled. I know they are harmless. I know they are one of the many wondrous species of wildlife that have unwittingly chosen me as their landlord. But now that I have seen a sloughed snakeskin a few yards from the house, I also know that the freshly clad previous inhabitant of said skin cannot be far away.
I have checked my trusty Readers Digest field guide to animals and it tells me they are common in lowland areas and found mainly in damp heaths, woods, lush pastures, damp grass and ditches where frogs kick about. The farm offers all of this, so just how many are out there, minding their own business but potentially causing me to lose mine?
A compost or dung heap is their favourite place for laying eggs and I cannot now visit the compost heap without an involuntary spine-shiver of fearful anticipation. And you should see the polytunnel - there is practically no visible ground, covered as it is with rampant cucumber, courgette, tomato and bean plants. Talk about the perfect amphibian hiding place. What do I do when I have to ferret amongst the cucumber plants to pick a beauty or two and mistake the soaker hose for something more animated?
There are nice damp jungly bits all over the farm where a snake could comfortably snooze and forage, conveniently hidden by the brambles that I am busy picking, no longer in pastoral crumble induced calm but in nervous hope that Hissing Sid will keep himself to himself.
Hundreds of eggs from multiple females may be laid in one place and the young are hatching right now. I have visions of plagues or at the very least, hysterics (my own) on a par with the commotion created by my coming face to face with rats en masse.