Are you tired of losing your squash plants to pesky vine borers? You’re not alone.
These destructive insects can quickly ruin your harvest and leave you feeling frustrated. But fear not, there are natural remedies out there that can help.
One such remedy is neem oil. But the question remains, will neem oil work for squash vine borers?
In this article, we’ll explore the effectiveness of neem oil as a solution for squash vine borers and provide you with some tips on how to use it effectively.
So, sit back, relax, and let’s dive into the world of neem oil and squash vine borers.
Will Neem Oil Work For Squash Vine Borers?
The short answer is yes, neem oil can work for squash vine borers. Neem oil is a natural, non-toxic remedy that can kill a variety of pests, including squash bugs and other cucurbit threats.
Neem oil works by smothering the eggs of the pests, making it difficult for them to feed on the leaves and limiting their reproduction. It is most effective on squash bugs while they are in the nymph stage.
However, it’s important to note that neem oil may not be very effective once the vine borers are inside the vine. In this case, surgery may be your best line of defense.
Additionally, neem oil can be toxic to bees and other beneficial insects, so it’s important to avoid using it on any flowering plants.
What Are Squash Vine Borers?
Squash vine borers (SVBs) are a type of moth that lay their eggs at the base of squash plants. Once the eggs hatch, the larvae burrow into the lower stems of the plant, weakening or killing it outright. The larvae feed ravenously from within the squash plant stem, devouring the soft tissues inside, causing wilting and eventual plant death. The squash vine borer moth is often mistaken for a bee or wasp because of its movements and distinctive red or red-orange coloring on a black body.
Found throughout the eastern United States, squash vine borers typically attack squash, zucchini, pumpkins, and various types of gourds. They prefer Hubbard squash and are not as fond of butternut squash. Other cucurbits, like cucumbers and melons, are not usually targeted. The borers overwinter in soil as pupae in cocoons. When the adult moths emerge in early to mid-summer, they lay eggs singly or in small groups at the base of plant stems. The eggs will hatch within 1 to 2 weeks of being laid. The larvae will then bore into stems to feed for about 2 to 4 weeks; sometimes they may also bore into the fruit. In northern areas of North America, there is usually only one generation per year; in southern areas, there may be 2 generations.
Squash vine borers are one of the most common and destructive pests, killing countless summer and winter squash plants each year. If caught early, it’s possible to save the plant. If caught after the eggs hatch, it may be too late. Controlling the squash vine borer is mainly about prevention.
The Damage Squash Vine Borers Can Cause
Squash vine borers can cause significant damage to your cucurbit plants by tunneling into the stems. The first symptom of a borer attack is wilting of the affected plants, which may occur only in strong sun at first. However, if the problem is left unchecked, the plants eventually collapse and die. Once the larva burrows into the stem of your squash plant, the injury can girdle the stem and prevent the plant from taking up any water or nutrients. This is what causes the plant to wilt, even though you may have recently watered it. If the wound in the stem is not closed, it can ultimately lead to the death of the plant.
Multiple borers can often be found in one stem, and several borer larvae may attack a single plant. The stem will start to rot at the site of the feeding first, and over time, the base may become mushy or rot away altogether. Borer damage weakens plants providing an opportunity for secondary infection, and in home plantings, infested vines are often completely girdled and usually become rotten and die.
It’s important to note that squash vine borers are an immature form of a moth, and these insects are not seen before their damage occurs. The adult moths will lay their eggs on the base of the stem of a zucchini, cucumber, melon, etc., and when the eggs hatch, the larvae will burrow into the stem of the plant.
If you find an obvious entry hole on the stem of your squash plant with frass around it, but your squash plant still appears to be healthy, surgery may be necessary to remove any larvae inside. A box cutter and a pair of tweezers can do the trick. First, make a straight incision down the stem of the plant (not across the stem which would sever it) where the hole is located. Cut as little as you have to until you spot the culprit or culprits if there is more than one. You’re looking for white grubs with a black head. Remove them with tweezers and dispose of them.
What Is Neem Oil?
Neem oil is an all-natural, non-toxic remedy that comes from the neem tree (Azadirachta indica), which potentially grows in USDA plant hardiness zones 10 through 12. It is one of the most highly effective types of horticultural oils that you can buy, and it works by combining five active chemicals similar to the hormones of many different insect species. When ingested, these chemicals make the bugs lose their appetites and stunt their growth. It even causes infertility in some female bugs.
Neem oil is effective in ridding the garden of a variety of pests, including squash bugs and other cucurbit threats. It works by smothering the eggs of the pests, making it difficult for them to feed on the leaves and limiting their reproduction. It is most effective on squash bugs while they are in the nymph stage.
However, it’s important to note that neem oil may not be very effective once the vine borers are inside the vine. In this case, surgery may be your best line of defense.
While neem oil is a natural and non-toxic remedy, it’s important to use caution when applying it. Neem oil can also be toxic to bees and other beneficial insects, so it’s important to avoid using it on any flowering plants. It’s also important to follow application instructions carefully and avoid spraying multiple chemicals on your plants at once, unless you know it’s safe to do so.
How Does Neem Oil Work Against Squash Vine Borers?
Neem oil works by combining five active chemicals that are similar to the hormones of many different insect species. When ingested, these chemicals make the bugs lose their appetites and stunt their growth. It even causes infertility in some female bugs.
In the case of squash vine borers, neem oil can kill the baby borers as they eat through the vine. However, it may not be effective once they are inside the vine. This is why it’s important to use neem oil as a preventative measure and to apply it in intervals of 7 to 10 days, at least a week before harvesting, especially if developing fruit are present on the plant.
It’s also important to note that neem oil may not be effective for every situation. If you’re dealing with a severe infestation of squash vine borers, you may need to use other methods such as Bacillus thuringiensis or spinosad spray.
How To Use Neem Oil To Control Squash Vine Borers
To use neem oil to control squash vine borers, you can create a foliar spray. Mix four teaspoons of clarified neem oil per gallon of emulsified water and pour into a spray bottle. Coat the entire plant, making sure to get the underside of cucurbit leaves as you go and ensuring a good amount gets onto any squash bugs you encounter. The spray dissipates after 45 minutes to an hour without leaving any residue, so it won’t harm beneficial insects or pollinators if sprayed around dusk or dawn.
Neem oil can also be mixed with Castile soap or Dawn dish soap to create a soapy solution. Mix equal parts neem oil and Castile soap in a small dish, then pour the soapy solution into a spray bottle and fill it with water. Spray the soapy water lightly over the surface of your garden plants to kill squash bug nymphs and other potential threats. However, it’s important to note that neem oil may not be very effective on squash vine borer eggs.
If you see squash vine borer adults, you can use Bacillus thuringiensis (Bt) to eliminate them and their eggs. Spray forms or powder forms of Bt will protect your plant against infestation. A spinosad spray can also be effective at killing off adult moths and their eggs. Apply these in intervals of 7 to 10 days, at least a week before harvesting, especially if developing fruit are present on the plant.
Finally, weekly applications of a chemical spray do work. However, chemical controls are risky to your pollinator insects, so you’ll have to determine if this choice is right for you. If you do opt to use chemicals, common ones used include carbaryl, permethrin, bifenthrin, and esfenvalerate. Remember to use an integrated pest management strategy to cover all your bases and avoid spraying multiple chemicals on your plants at once unless you know it’s okay to do so.
Other Natural Remedies For Squash Vine Borers
In addition to neem oil, there are several other natural remedies that can help control squash vine borers. One option is to use Bacillus thuringiensis (Bt), a naturally occurring bacterium found in soils around the world. Bt spray can be applied to the leaf stems and main stem of the plant, killing the squash vine borer’s eggs or larvae before they can cause damage. This method is favored by many organic farmers and may be the most effective way to deal with borers and other squash pests.
Another option is to use wood ashes, as suggested in The 1963 Old Farmer’s Almanac. While there is limited scientific evidence to support this remedy, some gardeners swear by it. Simply sprinkle wood ashes around the base of your plants to deter squash vine borers.
Yellow sticky traps and yellow-colored bowls of soapy water can also be used to trap adult orange moths, which are the carriers of squash vine borer eggs. By catching and destroying these moths, you can reduce the number of eggs laid on your plants.
Finally, planting a trap crop of very early-planted Hubbard squash can help alleviate pest pressure on other squash. The vine borers will be attracted to the Hubbard squash instead of your main crop, reducing the damage they cause.