Why People Put A Penny In Their Flower Vases (And What It Actually Does)

I love when there's a vase of fresh flowers sitting on my kitchen table. Yet, it seems like there's little time before the flowers start withering away (which is frustrating, because they're purely a treat). When I learned there was an old penny trick that could possibly help, I was eager to try it. After all, it requires nothing more than a penny! The only catch is that only a certain type would supposedly keep my flowers fresher longer. It had to be copper.

According to a PubMed Central article, copper is known for having antimicrobial qualities that help keep microorganisms at bay. But what I found interesting is that not all pennies are made of copper. Ones produced later than 1982 mainly consist of zinc, which doesn't have the same germ-fighting properties. That's why, to test out the penny trick, I had to do some change jar digging. I practically needed a monocle for the search. However, I eventually came across one from 1974 that'd work. Plus, I found a couple of extras, since I heard you can also put copper pennies in birdbaths.

In order to conduct a proper test, I decided I needed a control group in addition to the penny. Lucky for me, that meant I got to have TWO vases of flowers on my kitchen table. My husband brought home a lovely fall bouquet to split between two containers. But before doing so, I researched other tips to keep grocery store flowers fresh. That way, both sets of blooms could have the greatest chance of success. I started by washing the vases thoroughly, along with the penny. I filled them approximately 3/4 full of water, then dropped the penny inside the one with its corresponding label.

After cutting the stems at an angle, I plucked them clean so there wouldn't be any leaves underneath the water (an important tip I wish I'd known sooner). Next, I divided the bouquet equally into two bunches and placed them inside the vases. They looked completely identical besides the 1974 penny resting at the bottom of the group I was rooting for. The "plain" flowers had no other additions. All that was left to do was wait, observe, and enjoy having double arrangements.

A few days after setting up the experiment is when I noticed a real difference. Not in the flowers per se — but in the water. The "plain" vase was definitely hazier than the one with the penny. In fact, the penny version looked pretty darn clear despite it being three days later. Following a common flower tip, I decided to change out their water, once again filling the vases equally. I then plopped the penny back in.

It was within a couple of days that the cloudiness returned. However, this time, both vases were hazy. I do have to say, though, that the penny water continued to be not as bad. As for the flowers? Well, they looked rather similar (and decent). Some leaves were starting to wilt, along with petals on certain flowers. I was expecting there to be differences in their appearance and how fresh they seemed, but not so much. "Plain" was holding on as strong as "penny."

Both flower bunches were starting to look a bit sad a week into the experiment. Many blooms were drooping, the stems were slimy, and the water was even cloudier. But there were a couple of small differences I noticed. The "plain" vase had developed a ring of film on the glass (while the other hadn't). Also, when I changed their water once again, the control group seemed to have a fouler odor.

My end conclusion was that the flowers held up equally in terms of their longevity. Frankly, I thought they did pretty well. But I'm sure being mindful of their set-up and care helped the most — instead of just tossing them in a vase. Despite not being a total gamechanger, do I plan on dropping a penny into my future bouquets? Sure, why not! Just observing how it seemed to prevent some of the cloudiness is enough for me to keep a pre-1982 penny on hand (it's not like the trick was hard). I might even try out some flower arranging hacks to boot.