organic insect repellents

Garden insects a hot topic: Learn their organic antidotes

Most of the time I think of my garden as a peaceful place, full of beautiful flowers and fresh, juicy vegetables.  Sounds nice, doesn’t it?  But there are also days when it seems as though my garden is a war zone.  Like other gardeners, I’m fighting battles on many different fronts – there’s the heat, the drought, the weeds…and last but not least, pests.  There are many beneficial insects that help protect and pollinate our plants.  But there are also plenty of insects can plague a garden and turn gardeners sour.  There are approximately a million known different kinds of living insects.  Thank goodness less than 100,000 live in the United States, and approximately one-third of those can be found in Texas.

Many gardeners that I’ve visited with this summer are seeing unusually high numbers of insects in their yards and gardens.  Many insects are suffering from the drought just as we are, and are thus much more visible as they look for moisture from gardens and watered lawns.

Insects are just a part of gardening.   Some I just live with.  For example, the caterpillars attack my Texas Mountain Laurels in the spring, but my trees are mature and while they might not look good for a while, the caterpillars don’t do any long-term damage to the plant because they are well established.  And I know I will end up with so many beautiful butterflies and moths.

Some insects I feed.  I usually have parsley and dill in my vegetable garden to attract specific kinds of caterpillars, like the beautiful black swallowtail.

But some insects are not so nice.

In the vegetable garden, many pests are drawn to tomato plants.  Last year, my six 8-foot tall tomato plants were under siege by leaf-footed bugs.

Leaf-footed bugs

Leaf-footed bugs attack many different fruits and vegetables, including cotton, peaches, tomatoes, beans, and black-eyed peas. They also feed on the stems and tender leaves of plants like potatoes.   Leaf-footed bugs have piercing sucking mouthparts, which enable them to feed on plants through the sap flow in their leaves and stems.   They chew on leaves, stems and roots or suck the juices out of buds, fruit or other plant parts.

By the time I discovered them last year, there were platoons of adult pests with marching orders to reproduce, seek and destroy.  And destroy they did.  I tried everything organic that I could – neem oil, orange oil, insecticidal soap.  Sadly, according to conventional wisdom, there are no completely effective organic solutions for an infestation.  If caught very early, the bugs can be picked off by hand or sucked up with a tiny bug vacuum.  But once they’ve laid some eggs, it’s all over but the crying.  And cry I did, as we ripped out all the giant tomato plants.  With nothing left but empty wire cages, I was still able to count more than 200 that I squished by hand (with gloves on!) – as the bugs left behind roamed around the cages or crawled on the ground.  Still makes me shudder to think about it.  (Okay, I have a personal vendetta against leaf-footed bugs.)

Tomato Hornworms & Caterpillars

Tomatoes are also the favorite of Tomato Hornworms.  The giant lime-green squishy caterpillars can chew through tomato leaves in record time.  Luckily, the easiest treatment for them is to pick them off because they don’t multiply like other pests.  I quit squishing them when I realized that these caterpillars grow up to be sphinx, hawk, or “hummingbird” moths.  I generally relocate them to our woods to something green that I didn’t plant.  Watching a Hummingbird Moth is an amazing sight.  If you don’t want to get that close, you can use BT, Bacillus thuringiensis.  BT kills only caterpillars and doesn’t affect other beneficial insects.  But remember, using BT to kill caterpillars will mean that you will miss out on beautiful butterflies and moths.

Grasshoppers

Grasshoppers will eat just about anything.  They are part of the order that includes crickets, katydids and thousands of other insects.  Katydids will eat both plants and other insects, but grasshoppers are usually only interested in your plants.  Grasshoppers have strong jaws to chew their food.

Grasshopper infestations are particularly bad this year thanks to the drought.  Grasshoppers thrive in hot, dry conditions.   One of the things that holds down the grasshopper population is the growth of fungus in the spring.  But with no moisture, there has been very little fungus growth and that has helped grasshoppers thrive.

A swarm of grasshoppers can fly up to 15 miles a day.  Females can lay up to 120 eggs in a mass, and can lay between eight and 25 masses in her lifetime.

Neem oil, garlic oil or a blend of molasses, orange oil and compost tea are recommended organic treatments to control grasshoppers.  Another product used to control grasshoppers in the spring when they are in their nymph stage is Nosema locustae, which is sold as Nolo Bait.  This contains a parasite that specifically kills grasshoppers, but is safe for use around humans, pets, birds, and wild life and won’t contaminate waterways. It won’t harm beneficial insects and is widely approved for organic use.  But it must be used in the spring before the grasshoppers reach adulthood to work well.

Spider Mites

Spider mites are the some of the most prolific insects in the garden.  They are brown with eight legs and they lay their eggs on plants.  Lucky us — they like dry climates.  With conditions like our current drought, they can double their numbers in only 4 days.  They pierce plants and suck off the juice, causing leaves to curl and turn silver or yellow and covering them with fine webbing.  The key to controlling spider mites is to keep applying treatments every few days for 2 weeks.  Organic controls include orange oil, garlic pepper tea, insecticidal soap or liquid seaweed.

Pill bugs and sow bugs

Roly-polys are often the first experience young children have with bugs in the garden.  Many a child has been delighted watching pill bugs crawl around in shady places — picking them up to watch them curl into little balls.

These insects like shady and moist conditions. Young pill or sow bugs can live up to eight years.

Cayenne pepper, diatomaceous earth powder, and citrus oil can all help eliminate pill bugs.  Or, try the old home remedies of beer or grapefruit.  Cut in half and hollow out grapefruits or oranges.  Set them out like cups and the bugs will collect in them overnight.  The next day, empty the bug-filled rind into a bucket of soapy water to kill them.  Or, you can place some beer in a very shallow dish in your problem area overnight and you will awake to find dead pill bugs floating in the container.  At least with this method they will have died happy!

Aphids

Aphids are teensy little bugs, usually green, that feed by sucking plant sap.  They will attack most plants, usually on the underside of leaves and stems on new growth, causing leaves to curl and stunting new growth.    They can multiply by as many as 50 generations in a year.

There are many ways to combat aphids, including a good, simple spray with the hose.  Orange oil, garlic spray, insecticidal soap, and liquid seaweed are also effective.

Thrips

Thrips, often confused with invisible, biting no-see-ums, are actually plant pests. They are not no-see-ums.  They are less than 1/25” long and barely visible light green or yellow insects.  They suck the juice from plant cells and leave silver streaks or speckles on leaves.  On flowers, they will cause the edges to turn brown and stop opening.  Heavy rainfall can help control them, but in lieu of that, you can treat them with garlic tea, orange oil or neem oil.  They are natural predators of spider mites, so you might want to put your plants together to eradicate your mites before you kill the thrips.  (That would just be too much to hope for.)

Our extremely hot temperatures make it very difficult to treat plants for pests in the garden right now.  Applying any of these remedies at any time other than first thing in the morning will surely burn your plants and cause more damage than you started with.  Holding off until the weather cools just a little bit would be the safest approach.

There are many natural and organic treatments to control pests in the garden without harming the environment or other beneficial insects. Chemical pesticides in kill beneficials, upset the balance of nature, and leach harmful chemicals into wildlife habitats and our groundwater.  Using organic methods can help preserve our families and our environment for generations to come.

By | 2017-11-29T23:27:21+00:00 August 20th, 2011|Articles|0 Comments