That doesn’t mean companion planting does not work. It just means that you will need to test things out for yourself. One of the companion planting tenants that I have found some success with is interplanting vegetables to thwart insect pests. Like humans, insects have their preferred foods. Very often they find these foods by scent. We can make it harder for them to locate the buffet by mixing in plants that will confuse their sense of smell. This means you won’t be able to plant in tidy rows and large blocks of a single vegetable, but it doesn’t take a lot to have an effect.
Plants with pungent scents are among the most successful insect deterrents. Do your own study and test some of these near any vegetables you have reoccurring problems with and see if it makes a difference. Even if they aren’t as effective as you might hope, you’ll still have lots of herbs for seasoning.
1. Basil repels - Asparagus beetle, tomato hornworm. It’s the scent that deters the insects, so gently crushing the leaves as you walk by improves its effectiveness.
2. Borage repels - Tomato hornworm. Also attracts beneficial insects and pollinators. Allow it to self-sow.
3. Calendula repels - Asparagus beetle. It also attracts beneficial insects, so use throughout your garden.
4. Catmint repels - Aphids, asparagus beetle, Colorado potato beetle, squash bugs. The one drawback with catnip is that it tends to be an aggressive spreader. Really aggresive.
5. Chives repel - Aphids, Japanese beetles. This plant also tends to spread quickly, if you allow it to go to seed.
6. Dill repels - Cabbage moths. Dill is also a good plant for attracting beneficial insects and is a host plant for black swallowtail butterflies.
7. Garlic repels - Aphids, cabbage moths, Japanese beetles. Planting garlic under roses to repel Japanese beetles is a classic companion planting technique.
8. Horseradish repels - Colorado potato beetle. Unfortunately its hard to plant a perennial with a crop like potatoes, that need to be dug every season but it should have some effect if grown in the general vicinity.
9. Hyssop repels - Cabbage moths. A good companion for all sorts of cold crops.
10. Mint repels - Aphids, cabbage moths, ants. I’ve been experiment with just laying sprays of mint among the plants I want to protect, so that the mint does not take over the garden. It seems to be somewhat effective, but needs to be replaced often.
11. Onions repel - Aphids, carrot rust flies, flea beetles. The combination of carrots and onions has done well in testing. To foil flea beetles on my eggplants, I have been testing using onion peelings around them. I think the actual plants work better.
12. Oregano repels - Cabbage moths. This can be difficult to interplant, because it is a spreading perennial.
13. Parsley repels - Asparagus beetles. As with basil, you’ll need to gently crush the leaves to release the scent.
14.Radish repels - Cucumber beetles. For this you will need to seed 3 or 4 radishes in each hill and leave them there to mature.
15. Rosemary repels - Cabbage moths, carrot rust flies, Mexican bean beetles. Although rosemary is not hardy in all zones, you can usually find small plants inexpensively at the start of the season and you can always bring them indoors for the winter, as houseplants.
16. Sage repels - Cabbage moths, carrot rust flies. Sage is a perennial plant and can be hard to intercrop, but is still useful along the border.
17. Savory repels - Mexican bean beetles.
18. Thyme repels - Cabbage moths. Most thymes are low growing and double as ground covers in the garden.
19. Wormwood repels - Flea beetles. It also seems to deter mice. I have some of these plants here, some you will start from seeds. So give it a try...interesting and let me know if it works. Till next time, this is Becky Litterer from Becky's Greenhouse, Dougherty, Iowa