Non-Lethal Pest Deterrents in a Home Garden

Question

tl;dr version - How can I keep away destructive insects from the garden, without harming them or pollinators?

So first off, I'm torn between posting this here or the Gardening & Landscaping SE, but I think this would be the right spot because of the ethical concerns I have about trying to avoid killing bugs when I can avoid it.

So I've got a mid-sized home garden. The garden isn't 100% vegan (the base soil used included composted manure), but I'm working on making my own compost to use to amend the soil in the future.

Something I've been struggling with is how to deal with pests in a non-lethal way. Last week one of my zucchini plants was covered in Squash Bug eggs and recently hatched ones. I know that if left unchecked, they'll decimate not just that plant, but several neighboring plants. So what I did was cut off any leaf with the bugs on them, and buried the leaves in the compost pile to prevent spread to other plants. From the heat of the middle of the compost pile, this most likely killed all of the squash bugs. After doing this, I realized that I should really try to find a better way to deal with something like this, that doesn't involve out-right killing them all.

I'm looking to see if anyone's got suggestions for ways to deter initial infestations of plants, without killing bugs that come in contact with the plant. I wouldn't want to spray everything with a chemical that would then kill bees, butterflies, hoverflies, and other pollinators, but I want to keep the more harmful insects away.

Answer 1

Pest Deterrents in a Sri Lankan Home Garden

We live in Sri Lanka. Our garden is a third acre of manicured jungle with a house and a lawn in the middle.

The trees are all fruit trees, Coconut Palms, Oil Palm, Betel Nut Palms, (Areca), Mangoes, Papayas, Lime, Olive, Cinnamons, Bananas, Malay Apple, Bread Fruits, Jack Fruits, Jam Fruit, Pomelo, and a few more whose English names I do not know.

We have vegetarian pests including Aphids, Grubs, Slugs, Caterpillars, Grasshoppers, Thrips, Chipmunks, Rats, Peafowl, Monkeys. There is a Porcupine in the village that has done a lot of damage, but has not come into our yard yet. The biggest garden pest in Sri Lanka by far is the Wild Bull Elephant, luckily there are none in our area. The most irritating garden pest is the Mosquito.

We also have predators including Ants, Scorpions, Lizards, Chameleons, Frogs, Rat Snakes, (reports of a Cobra), Mongoose, Birds, (including a Kingfisher and Owls), Bats, and a Toddy Cat.

The garden seems stable, we have not lost plants to infestation or disease. (Knock on wood).

Our favorite predator is a juvenile Monitor Lizard. It was born two years ago, the offspring of a couple that often used our pool house for sex. It digs up a lot of lawn when it eats, but the lawn always grows back at least as thick.

The Monkeys are a bit of a pain, they take one bite of Mango or Malay Apple and throw the rest away. A dozen will sit in our Oil Palm munching the nuts and consume a whole season of fruit in one day.

We figure the Monkeys were here first and we are happy enough that they share the garden with us, and they are fun to watch. Things could have been worse, we might have had Elephants.