Will Flowers Die in a Hot Car?

by Alex Kountry
Updated on

We’ve all seen the news stories about children dying in hot cars. But what about flowers? Can they suffer the same fate?

Checkout this video:


It’s a hot summer day and you’re out running errands. You stop at the grocery store and pick up a bouquet of flowers for your kitchen table. You load your flowers into the car and continue on with your errands. A few hours later, you remember the flowers! You run back to the car, thinking they must be wilted by now. But to your surprise, they look as fresh as when you bought them! So, what gives? Will flowers really die in a hot car?

Here’s the thing: it depends on the flower. Some flowers are more resistant to heat than others and can withstand being in a hot car for a few hours without suffering any damage. Other flowers are much more delicate and will start to wilt almost immediately in high temperatures.

If you’re not sure whether your flowers will be able to withstand the heat, it’s always best to err on the side of caution and keep them out of direct sunlight or in a cool, shady spot. That way, you can be sure that your blossoms will stay looking fresh all day long!

What Happens to Flowers in a Hot Car?

You’ve probably heard the saying, “Don’t put your flowers in a hot car.” But what exactly happens to flowers when they’re exposed to hot temperatures? Let’s take a closer look.

The Science Behind It

It’s no secret that hot weather can wreak havoc on your flowers. But have you ever wondered what exactly happens to them when they’re left in a hot car?

The answer lies in the process of thermogenesis, which is the production of heat by an organism. This process occurs in all plants, but it is accelerated by warm temperatures.

When a flower is heated, the cellulose and pectin in its cell walls break down, releasing water and other molecules. This process is known as cell lysis. As more water is released, the flower begins to wilt.

The flower’s stomata, which are tiny pores on its leaves and petals, then close to prevent further water loss. However, this also prevents the plant from taking in carbon dioxide, which it needs for photosynthesis. The lack of carbon dioxide causes the plant to produce less ATP (adenosine triphosphate), a molecule that stores energy for cells.

Without ATP, the plant’s cells cannot function properly and begin to die. This is why flowers that have been left in a hot car for too long will often appear wilted, discolored, and lifeless.

So next time you’re tempted to leave your flowers in the car while you run into the store, remember the science behind why it’s not a good idea!

The Different Reactions Flowers Have

When the weather is warm, you may notice that your car windows fog up more quickly. The same principle applies to flowers in a hot car. If the outside temperature is hot and the car is closed up, the humidity in the car will rise. This increase in humidity can cause problems for flowers, especially if they are in a bouquet or vase without water.

Some flowers, such as orchids and bromeliads, are adapted to high humidity and will do fine in a hot car. Others, such as roses and lilies, need lower humidity to thrive. When exposed to high humidity, these flowers will start to wilt and their petals will become limp and droopy. In extreme cases, the petals may fall off entirely.

If you must leave flowers in a hot car for a short period of time, there are a few things you can do to minimize the damage. First, remove any leaves that would be below the water level in the vase. These leaves will rot quickly in humid conditions and can contaminate the water. Second, add fresh water to the vase before you leave so that the Flowers can drink as soon as possible when you return. Finally, try to find a shady spot for your Flowers so that they aren’t getting direct sunlight as well as heat from being enclosed in the car.

If you know you won’t be able to get your Flowers into water right away, cut an inch or two off the stems before you go. This will help them stay hydrated longer by reducing their leaf surface area. You can also try misting them with water if it’s not too hot outside. Just be sure not to leave them in standing water when you get home because this could promote bacterial growth

Tips to Keep Your Flowers Alive in a Hot Car

It’s summer time and the temperatures are rising, which means that your car is probably going to get pretty hot. If you’re going to be transporting flowers in your car, there are a few things you can do to make sure they don’t die in the heat. Here are a few tips:

Choose the Right Flowers

If you’re looking for flowers that will withstand the heat, look for blooms that are native to hot climates. These flowers have adapted to survive in high temperatures and will be better equipped to handle the heat than other varieties. Some of the best options for hot cars include:

-Desert roses
-Bird of paradise
-Canna lilies

If you’re set on a particular type of flower that isn’t typically found in hot climates, don’t despair. There are still steps you can take to help your flowers survive the heat.

Do a Trial Run

You wouldn’t run a marathon without training first, so don’t try to drive cross-country with a carload of flowers without preparing them (and yourself) for the trip. Do a trial run first, even if it’s just around the block. This will give you an idea of how your flowers will hold up in the heat and allow you to make any necessary adjustments to your method.

Be Careful with the Sun

Summertime is road trip time, which means your car might double as a makeshift vase for fresh-cut wildflowers or the grocery store bouquet you picked up for a dinner party. But before you start piling flowers into the cup holders and backseat windows, know this: Hot cars are deadly for blooms.

“The main thing that’s going to be happening to your flowers in a hot car is they’re going to be dehydrated,” says Lisa Mason Ziegler, a Florida-based commercial cut-flower grower and author of Cool Flowers: How to Grow and Enjoy Long-Blooming Hardy Annual Flowers Using Cool Weather Techniques. “So, you want to try to reduce that.”

The main culprit behind flower dehydration is evaporation, or water loss through the stems. When it’s hot outside, the air inside your car will quickly absorb the moisture in the flowers’ stems, causing them to wilt and die long before you reach your destination.

“If you put fresh-cut flowers in a vase on your dining room table, they’re going to last maybe five days,” Ziegler says. “But if you put those same flowers in a hot car for two hours, they might only last for two days.”

To keep your flowers alive and healthy during summer road trips (or any time the mercury rises), Ziegler recommends following these four tips:

1. Choose the right flowers.
2. Condition your flowers before hitting the road.
3. Bring along a cooler (and some ice).
4. Find a shady spot for your blossoms.


The answer to this question appears to be “it depends.” While it is certainly possible for flowers to die in a hot car, the circumstances under which this would happen seem to be relatively rare. In most cases, it seems that flowers are more likely to suffer from heat damage (such as wilting or drooping) than from outright death. However, if the temperatures inside a hot car are high enough, and the flowers are left inside for a long enough period of time, it is possible that they could die.

Photo of author

About the author

Alex Kountry

Alex Kountry is the founder of HayFarmGuy and has been a backyard farmer for over 10 years. Since then he has decided to write helpful articles that will help you become a better backyard farmer and know what to do. He also loves to play tennis and read books


HayFarmGuy - Get Info About Farm Animals in Your Inbox

Leave a Comment