The Ultimate Companion Planting Guide Part 1: Pest Prevention

It happens to the best of us. Hours spent planning, planting, and protecting your home garden and then ... a plethora of unwanted pests arrive. Aphids attack absolutely everything in sight. Cucumber beetles conquer your squash. Beetles bomb your brassicas and slugs slime your seedlings. Seemingly overnight, prized plants become sad sights with sticky residue, curling leaves, and stunted growth. 

So what is a home gardener to do?

Here at Pinetree Garden Seeds, we try to see the benefit of all the little creatures that enter our garden—but we’ll choose beneficial bugs over pesky pests any day! Stop fighting the forces of nature and start outsmarting them.

By proactively planning and planting your beds for pest prevention, you can preserve your plots without introducing pesticides and other damaging chemicals into our shared natural environment.

Gather your intel

Remember that all bugs are not bad for your garden and, in fact, some insects are your front lines of defense. Ladybugs and lacewings eat avaricious aphids. Some types of wasps attack caterpillars and grubs. And even beetles can be helpful at containing ground-dwelling pests. Just because you see a bug in the vicinity of a damaged plant does not make that bug a perpetrator. It might be a protector!

Now that you better know your enemy, survey your battlefield. Knowing your unwanted guests are coming can help you build better defenses. Watch carefully where and when particular pests converge. Which crops are the most attractive? And at which stage of their growth? Record your observations so that you can better decide which crops you need (or want) to protect and where to focus your attention.

Set your traps

The age-old practice of using trap crops can divert unwanted pests from your prized plantings and toward more sacrificial seedlings—naturally. Trap crops should be much more appealing to the pest than the plant you want to preserve and can be quite pleasant additions to your garden.

Because space is always at a premium in our test gardens, we like adding shade-tolerant varieties of trap crops beneath the sun-loving leaves of their taller neighboring crops. For instance, nasturtiums are fairly compact and are like candy to aphids while their attractive, showy colors can create eye candy for you.

Another favorite?  Radishes. Radishes sprout so quickly in the spring before other crops get going. When starving insects eat them up they start to develop a taste for those peppery leaves and will return to them even when other crops catch up. Try a few rows of radishes throughout your garden—they are an easy line of defense to replenish all season long!

Plant to attract beneficial insects …

If you are trying to protect plantings from caterpillars or grubs, chamomile, daisies, and mints can bring wasps and flies to police your beds. Worried about ground pests? Low-lying plantings provide shady cover for battalions of beneficial beetles. 

… and to deter destructive pests

The particular pests you are fighting will be unique to your microclimate and crops. Here at  Pinetree Garden Seeds in rural Maine, we find ourselves fighting aphids, Colorado potato beetles, Japanese beetles, ticks, and tomato hornworms.

• APHIDS
  Chives,  coriander, and the previously mentioned  nasturtiums are all great choices to control aphid populations.
  
  
• COLORADO POTATO BEETLES
  Try  catnip, tansy, or  sage to stop potato beetles.
  
  
• JAPANESE BEETLES
  Garlic, rue, and tansy can take on voracious Japanese beetles.
  
  
• TOMATO HORNWORMS
  Fennel is our favorite hornworm fighter—and it’s a delicious garden crop of its own. Whatever survives the hornworm onslaught you will be so happy to cook at home!

If you are trying to fight a different type of garden pest, you will be able to find plenty of suggestions online. You should also turn to local gardening groups or our Facebook group,  ROOTED, for experienced advice and encouragement. We are all in this battle together!

Be mindful of monoculture

If your garden is lacking in variety, you are inadvertently inviting pests to an all-you-can-eat buffet that they will keep coming back for. (And next time, they’ll bring friends.) Variations in size, shape, color, and aromas combine to overwhelm and bewilder bugs, distracting them from their favorite foods. (Imagine trying to find your favorite ice cream on a table piled high with treats!) 

If you have a particular crop that gets chomped, again and again, try planting multiple varieties that will bloom, set, and ripen at different times, or break up your planting across sections of your garden interspersed with other crops. Not only will you bewilder bad bugs, but you will also attract a variety of acceptable additions (like luring ladybugs to devour aphids).

Companion planting can go beyond bugs

Did you know that some plantings can help you avoid animals foraging in your garden as well? Lavender deters woodchucks, rabbits, and even deer. Deer also avoid any strongly scented plants, so planting  salvias,  sages, peonies, or iris around your vegetables can turn their appetites.

Through observation, experimentation, and lots of patience, you will soon find the best solution for your particular garden pest problems. And when you do, we’d love to know what worked!