There can be very little worse than trundling out to your veggie plot one morning, coffee in hand, and seeing nothing left but an array of spindly stalks, all their leaves eaten away.
At that point you know you have a problem.
Now, to be fair, the scenario I described above rarely happens unless a herd of deer or rabbits or wallabies have gone through your garden overnight. Realistically, your garden will have lots of insects, and that’s good. The more insects the better, because in a well balanced eco-system everything balances each other out, and while there may be lots of insects there that will like to munch on your vegetables, there will also be lots of insects (and birds) who will like to munch on the veggie-munching ones. My garden is a hive of buzzing critters and yet I suffer relatively little leaf-munching.
If you do go out one morning and see that your crop is being decimated, then your first problem is working out what is doing the decimating.
Very broadly, your problem is going to be either that large herbivores (deer, rabbits, wallabies, possums, whatever) have got into your garden, or smaller creatures – snails, insects, caterpillars and such like – are munching away uninhibited.
If the problem is the larger herbivores, then your only real solution is to fence off your kitchen garden. There are many products on the market which promise to scare away, or repel, various vegetable munchers, but in the end your only recourse is to invest in some fencing (this will also help keep out cats and dogs who might dig things up). It doesn’t have to be expensive fencing – often just some star pickets and chicken wire will be good enough – but fencing it must be.
If it is insects or snails doing the munching, then you have several means of removing the problem. First, identify the insect (or snail, or caterpillar) who is guilty (if you have absolutely no idea what it is, then take the creature down to your local plant nursery and they can identify it for you). Now, you can lay down bait, or spray with chemicals, but if you’ve got this far in my articles then you’ll likely realize this isn’t my favoured course of action. There are other, less harmful alternatives.
1) Don’t put your vegetable plants out into the garden until they are well grown – say, six inches in height and with several lots of leaves. Tiny seedlings are very vulnerable to insect or snail attack, larger plants not so much. You can’t do this with everything, but it is one way of avoiding the worst of predatory insect or snail damage.
2) Snails and slugs can be deterred by rough gravel or grit about the border of a garden (they hate crawling over it), by copper piping (I haven’t used this method, but I have heard it works), by simply going out there at night with a torch and picking them out and popping them into a bucket of water, or by constructing that great Australian invention, a beer trap. Half fill a wide mouthed jar full of beer (save some for yourself), then bury the jar of beer in the garden with the glass rim at soil height. The snails will make a bee-line for the beer, fall in, and drown indescribably happy. I’ve heard jam works as well as beer. Birds will also clean out a garden full of snails and slugs for you. I have lots of wild blackbirds who do that job for me, but chickens or ducks will work just as well. These are just a few alternatives to using a chemical bait.
3) Caterpillars – pick them off if you can, or hose them off.
4) Aphids. I have never tended to get much in the way of aphid infestations (I can put up with a few), but I have found that simply hosing them off works well, or you can use a garlic spray.
5) White-fly (tiny white critters that huddle on the underside of leaves) can be removed by, again, hosing off, or with white-fly traps. You can buy these or make them yourself – bright yellow-orange boards coated with a sticky substance. The flies will gravitate to them and you can just clean them off as you need.
6) Companion plant – mix up rows of vegetables to confuse vegetable-specific pests (carrot fly, for instance, can get confused if you intermix rows of onions with rows of carrots). Chives planted about the border of a vegetable plot can confuse some insects. Plants like basil, catnip and marigold repel insects and nematodes in the soil. Companion planting is a huge subject so do some googling on it if you are interested.
7) You can make up your own white oil spray to protect plants (no need to buy it as it is so easy to make yourself). To make a concentrate you can dilute as you need it, mix 2 cups of any vegetable oil with half a cup of washing up detergent (pick a bio-degradable one!) and store in a glass jar. When you need to use it, shake jar to mix the contents (they will have separated out in the meantime) and dilute into a garden sprayer at the rate of one tablespoon of concentrate to one litre (or one quart) of water. Spray with impunity, although don’t eat food from the garden after spraying for two days.
Hopefully your garden won’t need much in the way of insect control. I have never sprayed (apart from the odd white oil spray) and I don’t worry too much about a few leaves with holes in them. I have a well-mixed garden with lots of flowers and flowering shrubs about, and I find that nature itself balances everything out without any help from me.
My major worry is birds – mainly those pesky blackbirds as well parrots who eat fruit. The blackbirds, in their determination to find worms, can uproot an entire patch of seedlings in a few short hours, so I tend to net vulnerable garden beds to keep the blackbirds out. I also use plastic owls with fearsome eyes … but it didn’t take the blackbirds long to work out they were indeed, just plastic!
My fruit trees and soft-fruit bushes I net against parrots – it is the only way for me to get fruit off them.
Essentially, there are many old-world tricks you can use to keep your garden safe from predators before you need to try chemical sprays and baits.