Mosquito Plant, Pelargonium Citrosum – The Citrosa Plant

Home » Blog » Mosquito Plant, Pelargonium Citrosum – The Citrosa Plant

Robert Pavlis

The mosquito plant, Pelargonium Citrosum , also called the citrosa plant or citronella scented geranium, is highly recommended for keeping mosquitoes away. This plant is marketed as being specifically developed to continually give off a mosquito repelling scent. Turns out you can grow this plant in many gardens.

The mosquito plant has been confused by some in the horticulture industry, and falsely called the citronella plant. In Citronella Plant keeps Mosquitoes Away, I explained and clarified this mixup.

 

Mosquito Plant (Pelargonium'Citrosum')
Mosquito Plant (Pelargonium’Citrosum’)

Mosquitoes and Fragrant Geraniums

Pelargonium Citrosum is a strongly scented geranium that is reported to be very effective at keeping mosquitoes away. The University of Guelph tested the mosquito plant to validate the stated claims.

The researchers placed human subjects in a wooded area containing lots of mosquitoes. They then counted the number of mosquito bites each group of people received. People were randomly divided into 3 groups. One group tested DEET, another control group used water as a repellent, and a third group used water and sat beside a mosquito plant.

Microbe Science for Gardeners Book, by Robert Pavlis

The experiment had a variety of built in controls to ensure that they tested both males and females, both of varying size and age. Tests were repeated to produce statistically sound data.

Deet provided greater than 90% protection after 8 hours.

People sitting beside the mosquito plant had the same number of mosquito bites as people who were treated with water. That is to say – the plant had no effect.

The researchers commented that “during field evaluations, mosquitoes were regularly observed landing and resting  on the mosquito plant, indicating a lack of repellancy”.

Mosquito Plant Does Not Work

The results were quite clear. The mosquito plant does not work.

Pelargonium Citrosum is quite fragrant, but it did not work at keeping mosquitoes away. What about other fragrant plants – do they work? I’ve discussed that in Mosquitoes Repelled by Fragrant Plants.

References:

1) Field Evaluation of Citrosa Plant ‘Pelargonium Citrosum’, as a repellant against Mosquitoes;

https://pubmed.ncbi.nlm.nih.gov/8723261/

2) Photo Source: Mokkie

If you like this post, please share .......

Robert Pavlis

I have been gardening my whole life and have a science background. Besides writing and speaking about gardening, I own and operate a 6 acre private garden called Aspen Grove Gardens which now has over 3,000 perennials, grasses, shrubs and trees. Yes--I am a plantaholic!

15 thoughts on “Mosquito Plant, Pelargonium Citrosum – The Citrosa Plant”

  1. Oh no! I just bought Pelargonium citrosum yesterday, hoping to repel mosquitos off my balcony. I should’ve read about it first. Now what am I going to do with this… hm, maybe put cut leaves in the bathroom for scent. I hope it at least have pretty flowers…

    Reply
  2. Mine grew well indoors front enclosed porch over the winter here in Vermont. I was surprised because the woman who sold this plant to me saying it’s annual when I bought it like 4 inches tall last summer. But I doubt her now as it now grew tall like over 2 feet, and bottom sprouts new leaves! 😍

    Reply
  3. This plan is commonly used (very successfully) for years in Poland to treat ear pains (you have to roll it until juice is released and put it in the ear – use big leaf so you car remove it from ear canal). It’s also used for sore throat, and anxiety in form of tea.

    Reply
  4. While visiting Salzburg Austria and Seville, Spain, a few years ago, they told us that geraniums, visibly planted everywhere, were used to repel mosquitoes and other pests. While the true Citronella plant is probably the best for that purpose, it seems geraniums, Pelargoniums, do have a history of repelling of pests. Planted en masse along canals that I imagine were infested with mosquitoes, they also help with odors that one can be certain accompanied. These were just your basic pelargonium too not the scented type called Citronella.
    I am not sure any definitive answer can be known on this topic because mosquitoes are attracted to people with higher resting body temps, certain body odors based on what we eat, time of day, climate conditions, etc. I have low body temp and if I stand in a close to other people, they leave me alone. Thus, I find ‘true science’ often to be as subjective as folklore. The reality is that one will tend to ‘see’ information based on their hypothesis and miss important observations that don’t fit. It’s best not to take ourselves too seriously and if it works for you, that’s great. It does not, however, make it a wholesale, universal truth.

    Reply
    • “it seems geraniums, Pelargoniums, do have a history of repelling of pests” – just because people believe this, does not make it true. They do not repel mosquitoes.

      “I find ‘true science’ often to be as subjective as folklore.” – that is not true.

      Reply
  5. I had these about 3 years ago and I loved them. We could sit on our back porch and was never bitten. Went to my mom’s house which was only 2 houses away and got attacked soon as we opened the car door. I will buy these every year I can find them. Had 5 of them around a 10×20 porch

    Reply
  6. It is obvious that you do not value antidotal experiences at all and are on a quest to disprove these folks experience or perceived experiences. Realize that these folks could be the ten percent that didn’t meet your controlled group. Their soil could have the right elements to empower the plant to live up to its name. Or it affected their perception so much until their body put out its own repellant. And even if it doesn’t work. We do not have to challenge everyone that disagrees . . .

    Reply
    • I don’t dismiss anecdotal experiences, provided that the person making the statement also provides information about the control they used and the way they made measurements. But nobody does that. We just have a bunch of people making a change, and claiming it worked.

      That is the well known placebo effect – which has no real value if you are trying to understand the truth.

      Reply
  7. I bought 2 for around a garden bench and we have vicious attacking, biting flies in May. We get dive bombed on the walk to the garden, but are totally safe at the bench. I hope it works as well with mosquitos.

    Reply
  8. I had the pelargonium citrosum plants. They worked. However you have to agitate the leave occasionally to release the fragrance of the oils . Sometimes I would go so far as to rub a few leaves together and lightly tap it behind my knees and along my forearms and around my darker shirt collars. This stuff is green
    and you have to make sure you are not allergic. My problem is it’s a waste of money because, they did not hold up indoors over winter. Are they really perennials. Maybe I didn’t have enough sun light.

    Reply

Please leave a comment either here or in our Facebook Group: Garden Fundamentals