Why You Should (and Shouldn't) Grow Tansy

, written by gb flag

Harvested tansy flowers

Just when you think you can’t fall hopelessly in love with another flower, along struts tansy, and the fireworks go off again. Its ferny foliage captivates, its scent allures, and its quirky button-shaped flowers enchant. But only fools rush in, especially when they’ve been burned by unsuitable floral beaus before – I’m thinking of that aggressive mint, the over-ardent aquilegia, and the rambunctious periwinkle that I’ve dallied with in the past.

So, with plenty of painful experience to rein me in, I’m approaching a romance with tansy with utmost caution. There are few things more heartbreaking than ripping the roots of an adored plant from the soil (and having to do it over and over again for weeks, months, years…possibly forever) because it loves your garden a little too much.

Tansy has beautiful flowers but a sordid reputation

Reasons Not to Grow Tansy in Your Garden

When you’re first getting to know a handsome stranger it’s tempting to only notice his good points, but if you’re planning on entering into a long-term relationship it’s worth being realistic. Everyone has their dark side!

And tansy’s dark side is darker than most – it’s literally a killer. Despite historically being commonly used as a flavouring, bitter-tasting tansy contains a toxic essential oil that can cause liver and brain damage and even kill humans and other animals. On a less lethal level, it can also prompt an allergic reaction in some individuals when touching the leaves.

If that wasn’t enough to set the alarm bells ringing, tansy is also the type to make itself at home in your garden – a little too well! It both reseeds readily and spreads by underground rhizomes, so a flirtation with a few tansy plants could soon turn into a more permanent arrangement than you originally envisaged. In some parts of North America tansy is so invasive it’s actually listed as a noxious weed and is not permitted.

Approach growing tansy with care because it may become invasive

And Now Some Great Reasons to Grow Tansy

OK, so tansy isn’t perfect, but who is? A few flaws could almost be considered endearing…couldn’t they? All right, I admit – poisoning people to death is a pretty major flaw. So it’s got to have more to back it up than just a pretty golden face.

Fortunately, it does. That garden-grabbing nature means it’s happy in most soils and it doesn’t need feeding, so even those of us who are less than nurturing in our plant relationships can rest assured that we won’t ever neglect our beloved. Tansy can tolerate a little shade, making it useful for filling space in those less-loved parts of the garden, and once established it can cope with drought too. It will even help improve the soil because it accumulates potassium.

Tansy is also a staunch garden protector. There are impressive claims that it repels all kinds of pests such as ants, flies, fleas, moths, mosquitoes, ticks, and even mice. Yeah, yeah – I’ve heard that old line before! But the toxic nature of the essential oils in its leaves mean it can be used to make an insecticide, so perhaps there’s some truth in it. The strong-smelling flowers and leaves can be dried and gathered in a bouquet or used as part of a pot-pourri mix to keep bugs out of your house.

Growing tansy in a container can prevent it from taking over your garden

You’ll need to compete with some bugs for tansy’s affections though. Honeybees in particular find it irresistible, and ladybirds hold it in such high esteem they will seek out tansy to lay their eggs on. Tansy will host other pest predators such as braconid wasps and minute pirate bugs too. None love it more than the tansy beetle however, for whom tansy is ‘the one’ – no other plant will do!

While larger quantities can result in tansy poisoning, it’s said that small amounts of the leaves and flowers are fine to eat and can be used in omelettes, stews, salads and more. Personally, I think I’ll play it safe and pass on that one. You have to keep some mystery in any relationship.

So, I’m taking it slow with tansy. My plant is growing in a container where I can admire it but where it can’t move into my garden in a til-death-us-do-part kind of way. I’ve also planted feverfew, lupins, foxgloves and asters, because there’s no need to settle down with the first handsome flower that catches the eye. It’s still early days, but you know what? I think this one might be a keeper.

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Show Comments


"Very cleverly written and entertaining article!"
Mrs. Paul on Friday 17 July 2020
"Thanks Mrs Paul, I'm glad you liked it!"
Ann Marie Hendry on Friday 17 July 2020
"Personally I reckon the worst invader is the common orange day lily. It is impossible to dig out of the border, and I have large expanses if it, without a single flower! I am thinking of using weed killer as a last resort!"
carole on Thursday 23 July 2020
"That sounds like a real pain Carole! Can you restrict its spread with a barrier of some sort dug down into the soil? Hand-pulling would be the best way to remove some of the plants, although I appreciate it may not be easy. Reducing the overcrowding might also prompt them to flower better too."
Ann Marie Hendry on Wednesday 5 August 2020
"A delightful, amusing and entertaining article which will ensure I will not forget tansy's personal profile."
jeanne des baux on Tuesday 11 August 2020
"Thanks Jeanne, glad you enjoyed it!"
Ann Marie Hendry on Friday 21 August 2020
"I've got a few plants I plan on putting in the ground, but I'm worried about the spread (as is everyone, I suppose). I raise sheep, and am wondering, if it happens to work its way into their pen or the hay, will harm the animals or taint the meat? Anyone have any suggestions? "
Mary on Monday 17 May 2021
"Hi Mary, I admit I wasn't sure about this so I looked into it and it seems that sheep are often used to graze tansy (Tanacetum vulgare) and keep it under control, although it is poisonous to horses and cows. If you're worried about it spreading, I'd suggest planting it somewhere that you can mow around to keep it confined to one area."
Ann Marie Hendry on Friday 21 May 2021
"I, too fell for this handsome stranger and lived to regret it, although learning it does add potassium to the soil makes the angst a little easier to bear. Wonderful article! Thank you! "
Rob on Wednesday 9 June 2021
"thanks this article was helpful as I am just starting on the companion planting route. I think I will get tansy but keep it in a pot and well deadheaded. "
tracy h on Sunday 17 October 2021
"Sounds like a good plan Tracy."
Ann Marie Hendry on Wednesday 20 October 2021
"I thoroughly enjoyed your article, Ann Marie. I bought a small Tansy plant thou Etsy, because my favorite rose bush (Gemini) attacked by two insects. I researched the problem on the internet and ended up at Etsy and bought a small plant and some seeds of Tansy and Rue. I planted the small plant, not the seeds. I am trying to never use poisons of any kind. Within a day or three our Gemini rose tree became happy and healthy! Now I've been planning to spread this plant to my other roses. After further research, I'm hesitant. I'll think about it. Thank you for your article!"
Mary Renaud on Sunday 7 November 2021
"Hi Mary. It may be worth growing your tansy in a pot so that you can move it around the garden to where it's needed if you find it's effective at deterring pests, and this would also prevent it from spreading too aggressively."
Ann Marie Hendry on Tuesday 9 November 2021
"OOOOHHHH ok, I have a good size patch of this... bought a plant at a garden center claiming to repel flies. Long ago forgot what it's called.... Yup! Tansy. So... mine is in a spot in my flower garden, near a fire pit (party area.) Reading up today it suggests it repels ants too? I might have to try a potpourri this summer as ants are a constant problem all season long. Now mine has been in the ground for years. It did spread from my 4" pot size mild mannered friend into about a 4 FOOT patch. I simply cut it back to keep it in it's spot. Sure it spreads underground but lop it off at the base, pretty much keeps it under control. Butterflies seem to enjoy it, and I them so it's a win win. "
Jenny on Thursday 14 April 2022
"In response to Mary's query about having it around her sheep - our sheep seem to get high on it. They start to eat the fresh tips then they vigorously rub their heads into the plants. Very funny but they don't seem to have any negative effects from the plant."
Rhonda on Thursday 5 May 2022
"I've had a patch of tansy in my vegetable garden for over 20 years. It is easily kept in it's space by digging up any of those spreading roots. I like the scent and am glad to learn of the many benefits and perhaps that is why I have very few bug problems. Also, I really love them as cut flowers in the late summer and fall. They are long-lasting in the vase. Your photo really shows how charming they can be. Thanks for your article!"
Priscilla on Tuesday 28 June 2022
"Could you recommend a adequate size of plant pot that could be sunken in the soil to grow one Tansy plant."
John on Wednesday 13 July 2022
"John, depending on the size of plant you're starting with I'd use at least a 2 litre (half gallon) pot to begin with. The plant will root down through the drainage holes and gain more access to nutrients and water that way, so the pot doesn't need to be huge. It would be worth digging it up every winter and potting on into a larger container if necessary."
Ann Marie Hendry on Wednesday 13 July 2022
"As others have indicated, your article was very enjoyable to read. :-) I picked up 3 Tansy plants at a local Farmers Market earlier this year based on the seller's claim of its ability to repel bugs and its beautiful fern stems. The fern stems are beautiful. However, I planted these 3 amongst 4 tomato plants to repel bugs. We still had to deal with stink bugs, mites, and those monstrous green caterpillars! :-( You educated me on their death possibilities. I did read somewhere that they can be an abortifacient. So, your information seems consistent. With the clarity you bring out in your article and since I have backyard chickens, I believe I will now attempt to get rid of them. Thank you so much. "
Catherine on Thursday 25 August 2022
"I'm pleased you enjoyed the article Catherine, but sorry to hear that tansy didn't pull its weight in your garden. It may be better to settle down with a flower that knows how to give and take a bit more!"
Ann Marie Hendry on Friday 26 August 2022
"That is such a good article that's entertaining as well! I was just getting ready to plant a couple of tansies so am sure glad I read this in time. I'm going to keep them and grow in a 5-gallon smart bag."
Cathy on Monday 28 August 2023
"Thanks Cathy, glad you liked it! Containers are definitely the secret to a long-lasting relationship with tansy in many gardens. "
Ann Marie Hendry on Wednesday 30 August 2023
"Thank you for the article. It was really well written and informative. I shall give tansies a whirl in a pot :)"
tracey nettleship on Tuesday 5 December 2023
"A whirlwind romance! Have fun :)"
Ann Marie Hendry on Tuesday 5 December 2023
"Just dug up 3 Tansy plants . It’s said it spreads from rhizomes under the ground but I’m not to sure. It was popping up in close proximity to the original planted one but when removing it had a runner but it seemed to peter out. Unless it disperses its seed then the creates its own rhizome. Absolutely adore the scent it gives off. In the biodynamic garden book it states it repels codling moth . I planted mine within my apple tree gild but it never worked. Yes you can make an insecticide from soaking the leaves. To invasive for me. Like the mint family . Best in a pot."
John on Monday 4 March 2024
"I bought this plant at a yard sale and it was labeled yarrow. I dried it last year but haven't used it....I guess this will go in the compost pile. Grateful not to have shared any with anyone!! Always, always be careful correctly identifying your plants! "
Kate on Tuesday 11 June 2024
"Can Tansy have little white flowers instead of yellow ones."
Mike on Sunday 16 June 2024
"Sorry for the delay in replying Mike. I haven't heard of any white-flowered varieties of tansy, but if you have a clear photo of the plant, ideally showing both the flowers and leaves, please feel free to send it to us by clicking on the Live Chat button on this website, or email us, and we'll try to identify it for you."
Ann Marie Hendry on Wednesday 26 June 2024

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