I’ve written a lot on getting the best vase life for your dahlias— But my best recommendation is always to use a flower cooler. However, the backyard dahlia grower doesn’t often have access to a professional flower cooler. So today I’d like to share results of another method of getting great vase life from your dahlias.

The Boiling Water Method is often mentioned as being a way to extend the vase life of your dahlias. But what does that mean exactly?

To use this method: You boil water (an electric kettle works great!), give your dahlia a fresh snip at the bottom of the stem (about 1/4”), then dip and hold it in the boiling water for about 30 seconds. Then place it immediately in your vase for display.

I remember using this method the first year I grew dahlias. I didn’t have access to any professional methods of cooling my flowers. But I couldn’t really remember if it worked or not. So I decided to run my own trial.

I chose 6 stems of the same dahlia harvested at the same time/day. This is Cryfield Harmony. (Note: the yellow center is not a result of cutting too late, just a heat response, this trial was conducted in August in the South)

Here’s how I conducted the trial: Stems were harvested early in the morning into a bucket with just water. Then they were allowed to rest in a 65-70 degree room for a few hours. After a few hours, I divided them up. Jar #1- I recut the stems and placed them in a vase with just water. Jar #2- I recut the stems and placed them in a jar with water and the appropriate amount of flower food. Jar #3- I recut the stems, dipped into boiling water for 30 seconds and then placed them into a jar with water and flower food.

**I always use flower food in my vase water with dahlias because I know for a fact that it increases vase life. My goal here was to see if the boiling water actually gave any boost to the vase life in addition to the flower food. **

The blooms looked great for several days with no sign of decay. Stems were held in my living room which stays around 70 degrees. I did not change the water or recut the stems from day one to the end of the trial.

On day 6, I began to see signs of browning and fading on the dahlia in Jar 1 (just water).

On Day 7, I saw signs of fading/browning on the dahlias in Jar 2 and 3.

Jars 2 and 3 began to fade at the same time but I noticed that Jar 2 definitely faded faster whereas Jar 3 was only beginning to turn brown on some petals.

So what does all this tell me: Well obviously to get really accurate results, you’d need to repeat the experiment and also try it out with multiple varieties of dahlias. But generally speaking, boiling water doesn’t add any vase life over water with flower food.

My suggestion for increasing your vase life (for a backyard dahlia grower) remains to use flower food in your water. It’s just much easier and faster. If you don’t have flower food or don’t want to use it, then give the boiling water method a try- I think it would increase your vase life over straight water with no prior processing of the stem.

Notes:
What kind of flower food am I referring to: I use either Chrysal Professional #3 Vase Solution or Floralife Flower Food 300 - either works, whatever you can find. This is the white powdery stuff in the packets you get when you buy a bouquet. You can buy small pails of it on Amazon and other online market places.
Previous blog on increasing vase life in your dahlias- Click here.

Disclaimer: I know some people who swear by the boiling water method and if it’s working for you- then continue it! Keep in mind that health of plant, hydration and growing climate play a big role in the vase life of your dahlia. Most importantly— make sure you are enjoying them!!