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How can I make my cut flowers last longer?


Your primary piece of equipment to ensure long-lasting flowers of most varieties is a cooler. You need to be able to take the field heat out of the flowers and hold them until delivery at about 40 degrees.

One easy and inexpensive option is to build your own cooler. Many flower growers build relatively inexpensive 8×12 coolers using foam insulation, a store-bought 18,000-BTU window air conditioner, and a “CoolBot” — a $300 piece of machinery that helps the A/C unit to cool the space to as low as 35 degrees.

Cleanliness of all your tools is of utmost importance. The “godmother of flower farming,” Lynn Byczinski, likes to say, “Keep your vases as clean as your teacups.” The same goes for buckets and clippers. Install an easily accessible, easily cleaned bucket-washing station. Certified organic growers can use biodegradable soap for washing, along with a little bit of bleach or hydrogen peroxide for sanitizing. Wash and sanitize your buckets after every use.

Many flower growers use hydrators and preservatives in the water, but the research is unclear on whether or not these make a difference. Hydrators help the stems take up water efficiently from the first cut, ensuring longer vase life. Preservatives have a sugar to feed the flowers, and a bactericide to kill the inevitable bacteria produced—the “slime” that you see in a vase of old flowers. There is one hydrating and preserving product on the market that certified organic growers can use called Vita Flora .

Once you’ve installed a cooler, and have your squeaky clean buckets and clippers, the next step is timing your flower harvest. Flowers keep best when harvested in the cool morning or evening. In the morning, flowers are most turgid and very fresh. In the evening after photosynthesizing all day, they have the most carbohydrates to give them a long life. Either way, it’s best to harvest in temps under 80 degrees, while steering clear of times when dew is on the flowers. Wetness on the petals can lead to disease and fungus during storage. If you harvest in the morning, it’s important to hit that sweet spot between when the dew dries and the day gets too hot.

Every flower has its own peak time to harvest to ensure longer vase life. For example, sunflowers can be harvested and kept in the cooler the moment the first petal lifts from the center. That’s not the case for dahlias, which won’t open any further after you harvest. You’ll want to get to know each flower’s peak harvest time. Learning the ins and outs, and likes and dislikes of each specific flower can take years! That’s why it’s so important to work with other growers as you begin flower farming on your own. (Consider applying for a flower mentor through our Farmer-to-Farmer Mentor Program.)

The importance of cleanliness in flower harvest and handling can’t be emphasized enough, and that continues into how you cut and strip the flowers. Again, start with clean clippers. Most flowers can be cut and stripped in the field for efficiency and speed. But, if it has been especially rainy and the stems are muddy, you may want to cut the flowers and bring them to your processing area to strip the leaves and clean them up.

As you harvest, strip and put your flowers in buckets. Keep the harvested flowers in the shade, never in direct sunlight, and deliver to the cooler frequently as you go. Taking that field heat out of the flowers as quickly as possible after harvest does wonders for their longevity.

A few flowers do better when they’re not cooled, most notably, the zinnia. Zinnias like to be in the shade, but not cooled, and never harvested when they’re wet. I’ve learned that the hard way; they’ll turn to mush in a day or two.

You can ensure the continued longevity of your certified organic flowers when they’re out of your hands by educating your customers. Let them know to keep vases as clean as teacups, and replace the water and rinse the stems daily. To achieve even longer vase life, customers can give the flowers a fresh cut every other day, and display them out of direct sunlight. You have given your beautiful local, certified organic flowers a great start. By following these few easy tips, your buyers can enjoy them for several weeks.

Posted: Jul 2016
Answer By: Jennifer Nelson