You could define garden pests as those creatures of whom there are just too many. A couple of slugs and snails in your compost heap is good. The little blighters all over your garden is bad. I've dealt with the problem, in a chemical-free way, by spending many an evening collecting snails . . . (such a glamorous life . . .) This method, though, did work. It's all about restoring a balance. You don't need chemicals.
1997 was my first year of planting up the garden here. That June was, I believe, a month of record rain in our part of the world. The clayey soil of my garden provided a beautifully smooth surface for the progression of the snails that came out of the ivy covering the garden wall. I'd planted a lot of young plants, including things I'd grown myself from seed. These were fast disappearing under the attentions of the emerging snail army.
Despite this, I was totally against using slug pellets. We're not forced to see the unpleasant effects of the 'convenient' chemicals we use - perhaps we should be. Convenience for us so often comes at a price for some other species.
The solution seemed to be to venture out after dark and
with the aid of the outdoor security light that helpfully illuminated
at least part of the garden, collect up the snails I found. So for several
nights I went out with a bucket.
The following year, in the late Spring and early summer, I did the same, on the first few wet and mild evenings. The rather dismal nature of this didn't escape me: it really wasn't a fun way to spend a warm evening. All worth it though, as the sustained effort paid off.
I started gardening here, the garden was basically lawn, shrubs, and
trees, without a lot of plants at ground level that snails would like.
In 1997 they
emerged from the ivy to find a tasty and varied selection of succulent
young greenery, a salad bar for snails. My unprotected small plants, not
yet established, didn't have a chance.
Dangerous times might be in the first year or two of making a garden in an area previously left much to itself. Any pests will have been left to multiply at enormous rates. Once you start working over the ground you disturb the snail eggs, thereby reducing the numbers of new snails appearing.
In a newly-made garden the gardener is probably planting a lot of small, new plants. I've found that it's
important to protect these until they're big enough to withstand snail
attack. Later, with thicker stems and more growth, the occasional holes
in leaves don't matter. I'm
really careful when first planting out any young plants I know snails
and slugs like, and find that piling some sharp grit around them helps
to protect them in those initial stages.
Hostas I always plant in pots, with a thick layer of sharp grit in the top of the pot. And I stand these pots, if possible, away from walls or other surfaces that snails could travel from onto those succulent hosta leaves. (Incidentally, I've read, and found from my own experience, that the blue-leaved hosta 'Halcyon' is less prone to snail and slug damage.)
I store my captured snails in large plastic plantpots, upturned, with a piece of stone on top. The piece of stone I've found to be necessary to anchor the pot - snails, I'm sure, are cleverer than they look, and I'm sure they work collectively to unbalance any flimsy container . . . (!)
You then, of course, have a bucketful of snails (or several). Disposing of them depends on your ethical position. You can have a wander to the nearest piece of rough ground and liberate them there (Saying 'fly, fly, you're free' if you're as daft as we are, and have seen too many soppy 'animal released into the wild' films). You can dump them in your dustbin, which means they'll meet their end in the refuse collection lorry. You can stamp on them all, but this isn't pleasant if you've caught large numbers of them.
That common phrase 'snail's pace' is used to mean anything that crawls along at a slow speed. Yet I have to say that the little beasts can move at a fair sprint when they've escaped from the bucket you've put them in, and are zooming off towards your lettuces.