Tag Archives: organic pest control

Organic Pest Control: Japanese Beetles

A species of scarab beetle, these iridescent insects can be a nightmare for gardeners. Japanese beetles or Popillia japonica skeletonize the leaves of many plant species leaving just the veins. As the females eat throughout the early summer they lay eggs in the ground, eventually producing 40-60. Around midsummer, these eggs hatch into larvae which feed on grass roots until fall when they burrow 4-8 inches into the ground and go dormant for winter. In late spring they become pupae and eventually beetles which emerge from the soil and begin the cycle anew.

Solutions

If you struggled with Japanese beetles in your garden this summer, fall is the perfect time of year to take care of them. Here are a few ways you can control Japanese beetles in your garden.

Beneficial Nematodes

Beneficial nematodes or Steinernema feltiae are worm-like parasites that move through the soil and feed on Japanese beetle and other larvae. When beetles are in their larvae stage spreading nematodes on your lawn or around your fruit trees and garden can be effective.

Milky Spore 

Milky spore or Bacillus popilliae is a bacteria that attacks Japanese beetles in their larval stage. It can be spread on lawns and gardens. Apply before the ground freezes.

Chickens

If you have chickens giving them free rein of the garden or around fruit trees during fall and winter can help. Chickens actively forage for insects in the soil. While their incessant scratching can be a problem around your plants in the middle of summer it can be extremely helpful in the fall. They’ll dig up and eat the larvae. During the summer they’ll also enjoy eating the beetles but you’ll want to limit their time in the garden and fence off small plants that can be easily damaged.

If free-ranging your chickens even for a bit isn’t an option for you, consider putting up moveable fencing. A plastic deer netting will work in a pinch or you can invest in something electric netting which is easy to move, allowing you to rotate your chickens’ pasture.

Welcome-to-the-Garden Pollinator Collection

Wildflowers

Some studies (like this one from 2015), have indicated that wildflower plantings can increase insect biodiversity and the number of beneficial insects in gardens and reduce pest issues.

Floating Row Cover

While not necessarily the easiest solution, adult Japanese beetles can also be kept at bay with floating row cover.

Neem Oil

Some folks have also had success using neem oil to protect plants from adult beetles. It’s an organic pesticide and fungicide that’s used for a variety of garden problems and is available in many garden supply stores. It’s generally sprayed directly onto the plant. Multiple applications may be necessary throughout the season.

Crop Rotation & Cover Cropping

As always we recommend keeping your soil and therefore plants healthy by employing crop rotation and cover crops. Healthy plants are much less susceptible to pest problems. Fall is the perfect time of year for a soil test as well.

Sources

Organic Pest Control: Squash Vine Borers

Early White Bush Scallop Summer Squash

Squash vine borers are a type of clearwing moth. They’re a bit unusual because unlike other moths they’re active during the daytime. The adults resemble wasps, are about 1/2 inch long, and have an orange abdomen with black dots. The adults lay eggs near the base of squash plants. These eggs take only about a week to hatch and then they bore into the base of the squash plant and up inside the stem, preventing the plant from getting water or nutrients from the soil.

Signs of their presence include the plants wilting, holes at the base of the plant, and of course spotting adults flying around plants. If your plant has vine borers present you can slice into the stem and kill the insects. If you carefully bury the wounded part of the stem with moist soil and keep it well watered your plant may survive. While this is an option, the best methods for combating vine borers are preventative.

Plant late.

Depending on how long your growing season is you may be able to avoid vine borers by planting your summer squash at the end of July. Adult vine borers typically lay eggs in late June or early July so your late planting of squash won’t be mature until after vine borers are finished laying eggs.

Use crop rotation.

Once squash borers feed for 4-6 weeks they burrow into the soil where they spend the winter pupating. Rotating crops can help minimize the pressure on your plants.

Choose resistant plants.

Some cucurbits are much less likely choices for vine borers. Try planting squashes in the moschata and argyosperma family as well as watermelons and cucumbers.  Check out the post below for how to use young winter squash like summer squash.

Winter Squash as Summer Squash

Invest in row cover.

Covering your squash with row cover before late June can prevent vine borers from reaching your plants to lay eggs. This method needs to be used in combination with crop rotation as vine borers hatch from the soil.

Plant a trap crop.

You may be able to eliminate some of your garden’s vine borer population using a trap crop. Wait until your plants have vine borer larvae present and then pull and burn the plants. You may never get all of them this way but it can help reduce the problem next year provided you don’t have close neighbors also growing squash.

If you struggle with squash vine borers in your garden consider trying one of these preventative methods this summer. They can help you combat squash vine borers in without resorting to pesticides.

Organic Integrated Pest Management

As lovely and romantic as organic gardening can be it can also be really tough. A huge struggle for many organic gardeners is dealing with pests in an efficient and economical way without the use of pesticides or rodenticides. Developing an organic integrated pest management system or IPM can help.

Monitor & Identify

The first step is to monitor your garden and identify any pest issues. Record any problems in a garden journal and be as specific as possible. Research the type of pests you’re seeing and their life cycles, if it is an animal like a raccoon or squirrel you can reach Critter Detective squirrel control . Are they cabbage worms or cabbage loopers attacking your broccoli plants? Also record dates and conditions when they attack your garden. Do aphids destroy your fall crop of lettuce or do the only impact your spring sowings? The more you learn about these pests the easier it is to prevent them. You should also consider at this time if the pests are actually a problem. Having to pick off a few tomato hornworms may not be worth putting major preventative measures in place if they’re not actually affecting the productivity in your garden and are otherwise easily managed.

Prevention

This is the most important part of an IPM. Once you’ve gathered information you can put preventative measures in place. Knowing a pest’s habitat and life cycle can be key. Examples of of preventative measures include planting a crop late or early to avoid a major pest season (ex. planting quick maturing cabbage early when it’s too cold for cabbage moths), attracting certain bird species to keep pest populations in check, encouraging or purchasing native predatory insect species (ex. ladybugs can be purchased online and are excellent at reducing aphid populations), growing pest resistant varieties, or using row cover over your most vulnerable crops. Sometimes you’ll need to employ a combination of these strategies. Often a well planned preventative strategy can keep your garden productive without a lot of additional work.

Control

In severe situations where pest prevention has been ineffective control measures are used as a last resort. These controls may be very effective against pests however they’re typically costly in other ways. Some, like handpicking can be very time consuming while others may actually be pricey for the small gardener like neem oil. Even though they aren’t as problematic as chemical pesticides they also may have unintentional environmental impacts despite the fact that they’re organic. Organic pesticides like neem oil, diatomaceous earth, or milky spore powder may be implemented with the intention of only harming a single pest species but unfortunately there’s no way to protect the good species. These organic pesticides can still kill beneficial insects like butterflies, bees, parasitic wasps, predatory beetles, and more.

Using integrated pest management can help you successfully maintain an organic garden. While no strategy is perfect, researching and recording your specific pest problems and then implementing preventative strategies can be effective.

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