How To Get Rid Of Spider Mites on Rosemary? 6 Solutions [and 6 Tips]


Once you have colonies of spider mites living among your rosemary plants, it can be very difficult to get rid of them, but it’s not impossible. So that you don’t waste time with trial-and-error methods, here’s the short story:

The best way to get rid of spider mites is to use a combination of (1) general sanitation practices, (2) plants or predators as biological controls, (3) spray water and soap, essential oils, or (4) use carefully-chosen miticides and repeat until the mites are gone.

If your rosemary plants are dying despite your love and care, the problem may be too small to see, smaller than the dot at the end of this sentence. [01] That’s because spider mites are as small as 1/50 of an inch (or 0.4 mm), even when they’re adults. [02]

What Are Spider Mites?

There are many types of web-spinning, microscopic spider mites. These tiny cousins of scorpions, ticks, and spiders are difficult to see. In fact, it’s much easier to see their webs than their bodies.

Aside from the the tumid spider mite (Tetranychus tumidus), here are some of the most common spider mites in the USA. The numbers refer to links at the end of this article, where you can click to see their pictures.

  • Boxwood spider mite or Eurytetranychus buxi [03]
  • European red mite or Panonychus ulmi [04]
  • Honeylocust spider mite or Platytetranychus multidigitali [05]
  • Maple spider mite or Oligonychus aceris [06]
  • Oak mite or Oligonychus bicolor [07]
  • Spruce spider mite or Oligonychus ununguis [08]
  • Southern red mite or Oligonychus ilicis [09]
  • Two-spotted spider mite or Tetranychus urticae [10]

As we know, the aromatic oil of rosemary plant (rosmarinus officinalis) smells like forest pine [11]. Rosemary is also used to treat indigestion, arthritis, [12] and improve blood circulation [13]. In the kitchen, just a little rosemary can give a lemon-like flavor to any dish [14].

However, spider mite attacks can kill rosemary plants. Since these mini-spiders are almost invisible, many indoor gardeners are shocked to find entire spider mite colonies under the leaves of rosemary plants.

PRO TIP: House plants and home gardens with drip irrigation systems that do not wet the underside of the leaves are prone to spider mite infestations.

Many times, it’s only when the leaves fade, discolor, and fall off that most gardeners know they’ve got a spider mite infestation. If you see webs under the leaves, gently tap the leaves over a piece of white paper. If little dots fall and move on the paper, you’ve got mites.

How Do Spider Mites Spread?

Amazingly, spider mites are natural windsurfers [15], similar to self-powered windsurfing of lily pad beetles [16], of moths and butterflies that windsurf at 100km per hour on southerly winds, [17], and swans that windsurf. [18]

Researchers tell us how these tiny spiders use a four-step process to windsurf: [19]

  1. Anchoring: First, they use a few strands of silk to secure themselves to the ground.
  2. Wind testing: Then, they lift one arm (or leg) into the air to test the winds.
  3. Sail lofting: Then, the spider releases about 50 tiny strands of silk that act as sail.
  4. Anchors away: Finally, when a sufficiently strong gust of wind blows, the spider releases the anchor strands and windsurfs away over long distances.

How Do They Damage Plants?

Although scientists applaud their ability to use aerodynamics, gardeners consider spider mites as pests because they suck out chlorophyll, water, and nutrients from leaves. As a result, plants cannot photosynthesize. In addition, the trauma causes leaves to discolor and fall off. In the process, even small trees can die. [20]

The world’s three most common species are (1) the strawberry spider mite or Tetranychus turkestani, (2) the two-spotted spider mite or Tetranychus urticae, and (3) the Pacific spider mite Tetranychus pacificus. All thrive in warm and dry locations in the UK and in the USA. [21]

PRO TIP: White, yellow, or tan spots on leaves are often mistaken for nutrient deficiency, which is why spider mite infestation can become serious before it is recognized for what it really is.

Whatever type of spider mite attacks your rosemary plants, their life cycles and biological structures are similar. This article summarizes some of the best ways you can use to get rid of them.

6 Ways To Get Rid Of Spider Mites

These mini-spiders prefer to spin their webs in dry, undisturbed places where they lay eggs and multiply into large colonies. One easy solution to keep spider mites away from your rosemary plants is routine cleanliness. [22]

1. Practice Routine Cleanliness

This strategy is easy. The first thing you can do is to keep dust down by misting with a water spray. You can also implement the following routines to keep clean and keep mites away.

Inspect

Plants with a magnifying lens before planting or before moving them indoors. If you see spider webs under and between leaves, tap the leaves over a sheet of white paper. If you see moving specks, they’re spider mites.

Clean

All plant surfaces by spraying or wiping the plants with a sponge or cloth dipped in a solution of water and dishwashing liquid, particularly under the leaves. Rinse well and gently to avoid damaging the plants.

Wash

The plant in a gallon of room-temperature water mixed with about 2 spoons of dishwashing liquid. After a minute or two, rinse thoroughly. Repeat in 2-3 days if necessary.

Vacuum

Indoor plants to remove spider mites. Some indoor gardeners have been successful in using wet vacuums.

Prune

All heavily-infested plants when you isolate them. Immediately burn or sanitize infested leaves to prevent spider mites from spreading.

Shine

The leaves by wiping each one with a leaf shine every now and then: Some savvy indoor gardeners recommend using neem oil.

2. Use Water Correctly

Put simply, don’t let houseplant soil dry out. Spider mites hate moisture and high humidity. [46] To keep spider mites from your rosemary plants, regularly water it to keep it slightly moist. Here are four more popular methods.

Shower to Keep Clean

Wash your rosemary plants with water to remove dust that encourages spider mites. You can use either your sink, shower, or garden hose but be thorough and wet the undersides of leaves.

Wash to Remove Colonies

Water can also wash away spider webs, eggs, nymphs, and adult spiders. Do this at least once a week until you’re sure that all the mites are gone.

Water and Irrigate Regularly

Water your rosemary plants correctly and on schedule. Plants that suffer from drought stress are prone to mite attacks and damage.

Spray or Mist Below

Regularly use a water spray or mist to the undersides of leaves at least once a day. Use a humidifier or place indoor plants on trays with pebble and water.

3. Use Selected Plants

Use plants that spider mites hate. This strategy works best in gardens and farms where pesticide sprays are not used.

Spider mites hate veggies such as wild tomato, lettuce, chili pepper, okra, dill, garlic, and ornamentals such as pyrethrum chrysanthemums (mums), santolina, some types of crotons. [23]

Some gardeners swear by chives, onion, basil, cayenne pepper, cilantro [24], epazote [25], and the fungus Beauveria bassiana [26]. Others suggest fennel, coriander or cilantro, and cloves [27]

You don’t have to plant all of them. Choose only the companion plants that you want. However, if you plant more of these mite repellents, chances are that you’ll get better at repelling those pests. Also, you check out the Companion Planting Chart [28] for more information.

4. Use Natural Predators

Predatory mites and insects sold online can help you control spider mite infestations. Aside from ladybugs (Stethorus punctum) and the predatory mite Typhlodromus pyri [29], here’s a short list of other natural predators of spider mites:

  • All-purpose predatory spider mites or Neoseiulus Amblyseius fallacis [30]
  • Assassin bug or Reduviidae [31]
  • Big-eyed bugs or Geocoris spp. [32]
  • Green Lacewing or Chrysoperla rufilabris [33]
  • Gall midges or Feltiella acarisuga [34]
  • Lady beetles, spider mite destroyer, or Stethorus picipes [35]
  • Ladybug spider mite destroyer or Stethorus punctillum [36]
  • Minute pirate bugs, flower bugs, or Orius insidiosus [37]
  • Polyphagous predatory mite or Amblyseius andersoni [38]
  • Predatory mites or Phytoseiulus persimilis [39]
  • Six-spotted thrips or Scolothrips sexmaculatus [40]
  • Spical predatory mites or Neoseiulus californicus [41]
  • Two-spotted spider mites or Mesoseiulus longipes [42]
  • Western predatory mites or Galendromus occidentalis [43]

When you release these natural predators on your rosemary plants, they can consume hundreds of mites a day. However, after all the spider mites are gone, these insects can fly elsewhere to find food. If you want them to stay around, an insect house is a good idea. [44]

Once predatory mites are established in your garden or farm, they can reproduce and provide you with biological control for a long period of time, so that you don’t need to add more biocontrol agents – unless they’re killed off by nonselective insecticides. [45]

5. Use Natural Chemicals

Spider mites hate the smell of oil extracts from plants such as rosemary, peppermint, cinnamon, lemongrass, chamomile, horseheal (Inula helenium), caraway, marjoram, thyme, and certain types of curcuma. [26] A misting spray containing these oils should work for you.

In addition, a 2017 study found that essential oils from Bishop’s crown peppers and lemon drop peppers repel spider mites while oils from chile, jalapenos, cayenne and bell peppers kill about 45% of adult spider mites. [46]

Another option is using plant-friendly insecticidal soap or insecticidal oil made from plants such as cottonseed, canola, cinnamon, clove, or garlic.

Neem oil suffocates them while chamomile, coriander, spearmint, and rosemary are effective in killing spider mite eggs and adults. [47] These won’t harm the environment. You can buy these natural chemicals online or make your own.

PRO TIP: Don’t use soaps or oils on water-stressed plants or when the environmental temperature is more than 89°F.

6. Use Chemical Controls

For more serious infestations that require chemical control, be sure and test a small amount of organic insecticides or naturally-derived miticidal sprays on some plants before using.

Here a good one that I used often on my old rosemary plants.

The spray is made of natural products and non-toxic so it can be used for edible plants (veggie and herbs). It is recommended twice a week. This spray, as natural, might not have 100% efficacy but. This means that it will kill any mites on the plant, but it might not get rid of the eggs. If you want to avoid them at all cost you should use it at a more regular basis (3 times a week) so as to catch the baby spider mites so as to kill them before they reproduce.

Here are a few other tips to keep in mind.

Use Natural Insecticides

If an insecticide is needed, use an insecticidal oil, insecticidal soap, or a combination to cover the tops and undersides of leaves and buds. Use miticidal sprays derived from natural sources such as neem oil, pyrethrins, azadirachtin and horticultural oil.

Avoid Persistent Insecticides

Insecticides increase spider mites colonies. [48] when the insecticide kills off the mites’ natural enemies. In addition, during hot weather days, insecticides with pyrethroids, organophosphates, or carbaryl increase spider mite reproduction. [49]

Spray Again

Heavy infestations may need spraying several times with organic neem oil or insecticidal soap for indoor plants. To break the life cycle, follow the directions on the label, and spray at 3-day intervals but don’t spray when it’s very hot.

Warning 1

Don’t use oil-based sprays on plants that are growing under intense lighting, or in high temperatures (more than 80°).

Warning 2

When plants are showing buds, flowers, or fruits, use chemicals or miticides only as a last resort. As much as possible, use biological control methods only.

PRO TIP: Be careful when using miticide sprays. Some broad-spectrum sprays can also kill off natural predators and, as a result, spider mite populations increase instead.

Bonus Tips

To make sure that spider mites are truly gone, some indoor gardeners use the following extra remedies. [50]

Flour & buttermilk: After killing spider mites, keep new mites away with a mix of white flour, water and a little buttermilk. Spray on leaves once a week.

Habanero chili pepper bath: Wear gloves, chop habanero peppers, and mix with water in a large bucket. Dip the leaves in the pepper bath.

Neem oil: Mix 2 teaspoons neem oil, 1 teaspoon Castile soap mixed, and 1 quart lukewarm water. Spray on houseplants once a week.

Olive oil and garlic: Mix olive oil, 3 cloves of crushed garlic, hot chili sauce, dish soap, lemon juice, and water. Strain and spray on plants 3 times a week.

Rubbing alcohol: Soak cotton balls in rubbing alcohol and wipe the underside of the leaves of your houseplants. After a few hours, rinse the leaves thoroughly with water. If the leaves show signs of burn, dilute the alcohol with water ratio.

Vinegar: Mix 1/4 cup white vinegar or apple cider vinegar, 1 tablespoon baking soda, a few drops of liquid dish soap, and lukewarm water. Spray on plants until all spider mites are gone.

Takeaways

You’ve just completed a thorough review of anti-mite strategies to keep your rosemary plants healthy. Here’s a quick list of four (4) key takeaways to remember:

Identify: The first signs of spider mite damage are light dots on the leaves of dusty and water-stressed plants. The leaves later turn yellow and die.

Isolate: Spider mites are windsurfers and ride breezes and gentle winds. Isolate infested plants to prevent the spider mite problem from spreading to other plants, homes, and gardens.

Clean the leaves: Wipe houseplant leaves (particularly the undersides) with a damp cloth to humidify leaves and to remove tiny mites before they damage the plant.

Use beneficial insects: Use beneficial insects to consume spider mites. Do not use pesticides on your plants.

And that’s it! If you have questions or something to add to this article, please let me know! I look forward to hearing from you.

yourindoorherbs.com is part of the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites like mine to earn advertising fees by promoting good quality Amazon.com products. I may receive a small commission when you buy through links on my website

Sources

[01] https://www.sciencedaily.com/releases/2009/11/091102171613.htm by Science Daily

[02] https://ohioline.osu.edu/factsheet/HYG-2012-11 by David J. Shetlar, Department of Entomology, Ohio State University Extension

[03] https://bugguide.net/node/view/1671127 by Bug Guide

[04] https://www.cabi.org/isc/datasheet/33684 by Invasive Species Compendium

[05] https://ohioline.osu.edu/factsheet/HYG-2012-11 by David J. Shetlar, Department of Entomology, Ohio State University Extension

[06] https://content.ces.ncsu.edu/maple-spider-mite-oligonychus-aceris-shimer-acariformes-tetranychidae by Steven Frank and Adam Dale, North Carolina State University

[07] https://en.wikipedia.org/wiki/Oligonychus by Wikipedia

[08] https://wiki.bugwood.org/Oligonychus_ununguis by Bugwood Wiki

[09] https://edis.ifas.ufl.edu/in680 by H. A. Denmark, W. C. Welbourn, and T. R. Fasulo, Institute of Food and Agricultural Sciences (IFAS), University of Florida

[10] https://en.wikipedia.org/wiki/Tetranychus_urticae by Wikipedia

[11] https://ag.umass.edu/fact-sheets/rosemary-container-production-for-december-market by the University of Massachusetts Amherst Center for Agriculture, Food and the Environment

[12] https://www.webmd.com/vitamins/ai/ingredientmono-154/rosemary by WebMD

[13] https://www.flushinghospital.org/newsletter/the-health-benefits-of-rosemary/#:~:text=Rosemary%20is%20a%20rich%20source,alertness%2C%20intelligence%2C%20and%20focus.by the Flushing Hospital Medical Center

[14] https://www.cookinglight.com/cooking-101/essential-ingredients/all-about-herbs-slideshow by the Allrecipes Food Group

[15] https://www.gardentech.com/blog/pest-id-and-prevention/spider-mites-tiny-bugs-that-cause-big-problems#:~:text=Spider%20mites%20are%20so%20small,are%20much%20easier%20to%20see. by Tiffany Selvey, Garden Tech

[16] https://www.nytimes.com/2016/03/07/science/an-insect-that-masters-water-and-air.html by James Gorman, The New York Times

[17] https://www.yorkshirepost.co.uk/news/windsurfing-insects-move-100km-hour-1988990 by Yorkshire Post

[18] https://www.sciencedaily.com/releases/2016/10/161021084340.htm by Science Daily

[19] https://www.popularmechanics.com/science/animals/a21565320/amazing-footage-reveals-how-spiders-fly/ by Avery Thompson, Popular Mechanics

[20] https://www.gloucesterva.info/ArchiveCenter/ViewFile/Item/494#:~:text=According%20to%20the%20University%20of,to%20absorb%20energy%20from%20light. by Susan Camp

[21] https://www.planetnatural.com/pest-problem-solver/houseplant-pests/spider-mite-control/ by Planet Natural Research Center

[22] https://www.guide-to-houseplants.com/spider-mites.html by Guide to Houseplants.com

[23] https://www.hunker.com/12540116/plants-that-keep-spider-mites-away by Jamie Conrad, Hunker.com

[24] https://www.permaculturenews.org/2017/02/06/repel-pests-plants/ by Richard Bogdanowicz, Permaculture Research Institute

[25] https://pubmed.ncbi.nlm.nih.gov/15384351/ by H.Chiasson, C. Vincent, and N. Bostanian in Journal of Economic Entomology.

[26] https://www.nature-and-garden.com/gardening/red-spider-mite.html by Gaspard Lorthiois, Nature & Garden

[27] https://www.houzz.com/discussions/2135381/spider-mites-and-companion-plants by Ellie, Houzz.com

[28] https://www.permaculturenews.org/2013/06/20/companion-planting-chart/ by Stefan Boone, Permaculture News

[29] https://www.sciencedaily.com/releases/2009/11/091102171613.htm by Science Daily

[30] https://www.buglogical.com/spider-mite-predator/spider-mite-control-neoseiulus-fallacis/ by Buglogical Control Systems, Inc.

[31] https://plantcaretoday.com/assassin-bug.html by Plant Care Today

[32] https://plantcaretoday.com/assassin-bug.html by John R. Meyer, Department of Entomology, North Carolina State University

[33] https://entomology.ca.uky.edu/ef148 by Ric Bessin, University of Kentucky College of Agriculture

[34] https://en.wikipedia.org/wiki/Feltiella_acarisuga by Wikipedia

[35] http://ipm.ucanr.edu/PMG/NE/spider_mite_destroyer.html by University of California Agriculture and Natural Resources

[36] https://en.wikipedia.org/wiki/Stethorus_punctillum by Wikipedia

[37] https://www.arbico-organics.com/product/minute-pirate-bug-orius-insidiosus-predator/beneficial-insects-predators-parasites by Arbico Organics Resources

[38] https://naturalenemies.com/predatory-mites/amblyseius-andersoni/ by Natural Enemies

[39] https://www.biobestgroup.com/en/biobest/products/biological-pest-control-4463/beneficial-insects-and-mites-4479/phytoseiulus-system-4668/ by Biobest Group NV

[40 https://academic.oup.com/aesa/article-abstract/70/1/11/8737?redirectedFrom=fulltext by Pamela Coville and William Allen, Entomological Society of America

[41] https://www.arbico-organics.com/product/mite-predator-neoseiulus-californicus-spidermite-killer/pest-solver-guide-mites by Arbico Organics

[42] https://mlachapell.com/two-spotted-spider-mites-tssm/ by Moriah LaChapell

[43] http://treefruit.wsu.edu/crop-protection/opm/western-predatory-mite/ by Stanley C. Hoyt and Elizabeth H. Beers, Washington State University

[44] http://www.bbc.co.uk/breathingplaces/bug_home/ by the British Broadcasting Corporation

[45] https://www2.ipm.ucanr.edu/agriculture/citrus/Selectivity-of-Insecticides-and-Miticides/ by the University of California Agriculture and Natural Resources

[46] https://journals.ekb.eg/article_12101_3cfcc0e044d2518793cdf580fa285605.pdf by Ashraf S. Elhalawany and Ahmed A. Dewidar in Egyptian Academic Journal of Biological Sciences

[47] https://leafyplace.com/spider-mites/ by Leafy Place

[48] https://blog.pestprophet.com/sulfur-fungicide-use-powdery-mildew-control-hops-may-increase-spider-mite-populations/ by Pest Prophet Blog

[49] http://ipm.ucanr.edu/QT/spidermitescard.html by University of California

[50] https://www.growerstrust.com/blogs/news/15636757-organic-tips-to-get-rid-of-spider-mites by Growers Trust

Andrea

A young Italian guy with a passion for growing edible herbs. After moving to the UK 6 years ago in a tiny flat, it was impossible to grow herbs outside. So I start my journey in growing indoor and so I decided to share my knowledge.

Recent Posts