I Tested the Viral Trick for Revamping Cut Hydrangeas—and It Worked

Hydrangeas are really having a moment. The blooms are bigger, the colors are brighter, and it feels like they’ve become the official floral icon of summer.

But if you’ve ever bought cut hydrangeas, you know they’re not particularly long-lasting. While you can of course dry and preserve your cut hydrangeas, it’s not the same as a fresh bunch of stems.

So, when I saw this hack from Skye Hamilton of @hamiltonhousedesigns to help them last longer, my interest was piqued.

The only problem? The hack seems very, very strange! 

To recap, these are the steps:

1. Once you notice your hydrangeas are either wilting or have fully wilted, fill a bowl with cold water.
2. At the same time, fill a pot with water and heat it to not quite boiling. 
3. While that heats up, dunk each hydrangea head in the cold water.
4. Fill your vase with the not-boiling water.
5. Pour a small amount of alum powder into a bowl.
6. Trim your stems at a forty-five-degree angle. 
7. Dip the stems in the alum powder. 
8. Arrange the flowers in hot water. 

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First, Buy Hydrangeas

I popped around to my local florist to find the hydrangea supply was slim. At first I was bummed, but then I realized it could be a great chance to see if this trick was varietal-dependent. 

I picked three stems with three different looks, asked the florist to trim the stems for me, and plonked them in a vase of cold water as soon as I got home.

Within a few hours, Hamilton offers video proof that your near-dead hydrangeas will perk back up and come alive again. I had to set out to see for myself. 

Next, Monitor Their Health and Happiness

For the first day or so, my new hydrangeas did their job: brought some color and joy to our kitchen. Within forty-eight hours, however, the first of the bunch started to wilt.

I gave it another twenty-four hours and noticed a second was joining the first on its quest to die. As the petals curled and lost their color, it was clearly time to try the hack.

Steps 1-4: Prep the Water and Dunk

The first three steps of the process didn’t feel too abnormal or foreign to me, as far as cut-flower maintenance goes.

Hydrangeas are named for their love of water, after all, so dunking the heads in a fresh, cold bath seemed like something they’d enjoy. Plus, I figured they must be used to it in rainy London. 

The hot water did give me pause, but I’ve also heard that warm water can help the flower buds on your cut stems open quickly. Perhaps this was all part of the magic?

Step 5-8: Use Alum Powder and Arrange

It’s the next part that I was completely new to me. As it turns out, alum powder is often suggested as an alternative to homemade flower food, so in retrospect, it’s not that wild. But before this, I only knew it as something most commonly used to pickle things or tenderize meat.

For flowers, though, it turns out alum powder helps the stem draw more water. This is especially true for flowers with woody stems, like roses and, yes, you guessed it: hydrangeas. 

I followed the instructions, and dropped my alum-soaked stems in their not-boiling water. 

The Final Results? Wow!

I was dubious about this entire process, I must admit. Mostly because none of my hydrangeas looked like the ones in the original video, and by the time I decided to try it out, the largest of the three looked more shriveled and dry than limp and wilted. 

My confidence didn’t improve when about two hours later, the flowers looked the same. Six hours later, I saw some improvement, but I also wondered if it was in my head.

A full twelve hours later, however?

The almost-dead stem of the bunch had perked up a ton, and the other two looked absolutely perfect.

Best of all, it was an incredibly easy process. It really didn’t require anything more than my usual bouquet maintenance of occasionally swapping in some fresh water and re-trimming the stems, just with the added steps of hot water and alum powder.

Consider me converted—I’m going to certainly use this hack from now on.