Long legs and multiple sets of eyes have made spiders the stuff of nightmares and horror flicks. But despite their scary appearance, most spiders are not a threat to humans. Although many of them will bite if provoked, only a couple in the United States are cause for concern due to their highly toxic venom: brown recluses and black widows. Spiders are one of the most beneficial creatures in the garden because they live on insects and other spiders. Still spiders in large numbers can be unsettling, and repelling them can be a challenge, especially in an evergreen. Fortunately, there are safe and natural ways to get your evergreen back to being spider free.
Along Came a Spider
The first thing you should ask yourself when your evergreens are overrun by spiders is “Why are they here?” Spiders, like any other creature, will follow food sources. Spiders eat a large variety of insects, so finding the insects plaguing your evergreens may be a good place to start in ridding your tree or shrubs of spiders. Basic insect prevention includes keeping the area around the base of the evergreens free of weeds, debris and other hiding spots. Maintain the yard so that it doesn't attract food for the spiders; for example keep lids of trash receptacles tightly secured so they don't attract bugs. If you have fruit trees in your yard, make sure to pick up any fruit that is rotting on the ground, which will attract insects. Also, keep wood piles away from your evergreens. Black widows like to hide in wood piles. Spraying the evergreen bushes with water will also help. The spiders will bebuild their webs, but if you hose daily, they may go elsewhere.
Essential oils are becoming a popular alternative to chemicals in repelling spiders. Among the most effective for repelling spiders are peppermint, tea tree, eucalyptus, cinnamon, citronella, citrus, lemon, lavender and clove bud oils. Mix 4 to 5 drops of oil in a gallon of water containing natural biodegradable soap, increasing the concentration of oils if needed. Saturate cotton balls with the essential oil mixture and place throughout the evergreen or directly spray spiders. Because essential oils oxidate quickly, several applications, using a fresh batch each time, may be necessary. For best results use therapeutic grade essential oils. for best results. When ingested, essential oils can be toxic. Some are poisonous to pets, including tea tree oil. When undiluted, some can burn the skin and eyes. Use with caution around children and pets.
Some Like it Hot -- And Some Don't
Spiders don't seem to care for hot peppers. Hot pepper sauces with the best reported successes have habanera or jalapeno peppers in them. To make a hot pepper spray, combine 1 ounce of hot pepper sauce to 8 ounces of water containing natural biodegradable soap. When using, spray directly toward the spider. Avoid getting it in your eyes because it can cause extreme burning. For this reason, it is best to keep it out of the reach of the kids. Undiluted, hot pepper juice can blister the skin.
To Trap a Spider
If spraying sounds like too much of a hassle, another option for getting rid of the spiders plaguing your tree is to set spider traps. These are safe and non-toxic and can usually be purchased where pest control products are sold. They come as unfolded boxes with square areas in the middle covered with wax paper. To use, simply remove the wax paper and fold them into boxes. The area underneath the wax paper is covered with a sticky substance that attracts the spiders. Although traps work best indoors, they may be tied or taped to a tree. But, if your evergreen is small, a trap may not be practical. Traps must be kept out of the reach of curious pets and children because the trapped spiders will bite if given the chance. The Journal of Arachnology reports that crab spiders can be trapped using cottonballs drenched in basil or clove oils and then released. Most commercial traps do not allow for spiders to be released.