Cut flowers — How to preserve cut flowers for longer-lasting arrangements
February 13, 2020
During the winter months, I have a small budget dedicated to cut flowers. (In the summer months I mostly grow my own.) Were that budget bigger, I’d have a vase of flowers in every room of our house! Even if I only manage one vase though — or maybe especially if I only have one vase — I like to do everything I can to keep them looking beautiful for as long as possible.
Of course, there are days when I arrive home with flowers, and the best I can manage is plopping them in a container of water until hours later. And occasionally all there’s time for is sliding them in a vase of water for the table right before guests arrive.
Usually, though, I do what I can from these best tips for keeping cut flowers fresh:
Keep them hydrated!
This is the most important thing to know about cut flowers. They need to stay hydrated or they’ll faint. Without plenty of fresh water, they’ll be a scraggly, wilted, sorry mess in no time.
Flowers appreciate being plunked in water the minute they’ve been cut. I bring a pail of water out to the garden with me when I cut flowers to bring indoors. And I occasionally bring a bucket of water in the car when I’m buying flowers for an event. I simply have the bottoms of their stems left unwrapped, and then I set them in the water for the ride home.
This isn’t always practical, of course. Just keep in mind when purchasing or being gifted flowers, that the sooner you get them in water the better.
Cut the stems.
When you get your cut flowers home, give the stems a fresh cut. Some tips about the cuts:
•Use a sharp knife or floral shears rather than scissors or pruning shears. That’s because scissors and pruners can squash the tissues in the stem, preventing maximum water absorption up to the flower.
•Ideally, make your cut with the stems under water (in a sink or basin of water, for example). This will keep air bubbles (which can decrease water absorption) from getting into the stems.
•Cut each stem right above a node (those bumps on the stem — this is where leaves grow). Water will travel up the stem more quickly if you cut above rather than below the node.
•Make your cuts on a 45-degree angle. An angle will provide maximum water exposure. It’ll also prevent the stem from sitting flush with the bottom of your vase, which would cut off water absorption.
•If the stems are woody, cut an “x” in the bottoms, to allow more water to enter. If the stems are too narrow to manage an “X,” simply make a “/.”
After their first cut, let the flowers sit in fresh water in a bucket or other container in a cool, dark place. Leave them for a couple of hours or more, if you can. This will revive them so they look their best for your arrangement.
Prepare your vase.
Whether you’re using a fancy cut-glass vase, a lovely little bud vase, or a canning jar, make sure it’s sparkling clean. Bacteria will quickly cause your stems and flowers to decay.
Fill your vase or container three-fourths full of water. Know those little packets of preservative florists tuck in your cut flowers at the store? Sprinkle some in, according to the package directions. The preservative contains a biocide to kill bacteria, something acidic to help the stems soak up the water, and a sugar to feed the flowers.
Prepare each stem.
Remove any foliage that will sit below the waterline when the stem is in your vase or vessel. (Underwater leaves can rot and cause a slimy, stinky mess.) Also remove any dead leaves or extra leaves. Often there will be more leaves on a stem than you want in your arrangement.
When preparing roses, remove the “guard petals,” those outer couple of petals. This will encourage the flower to open more easily.
Give each stem a fresh cut and add to the vase of water as you cut them.
Maintain your arrangement.
If possible, keep your flowers out of direct sun and away from any heat source. Keep them away from fruit, too, because the ethylene gas emitted by fruit can cause them to deteriorate more quickly.
Whether your arrangement is a carefully styled array of roses or a whimsical bouquet of wildflowers, it will need the same maintenance. Every couple of days, take the flowers out of their container, and wash and refill the container with fresh water and preservative. Give each stem a fresh cut, remove any dead or loose petals, and put them back in the water.
Flower experts have conducted longevity tests to see what tips for keeping cut flowers fresh pan out. Adding aspirin, a penny, Vodka, vinegar, soda, or bleach to the water (all often-recited tips for making cut flowers last) had insignificant (or detrimental) results. The top way to preserve flowers, they found, is to place them in the refrigerator overnight. If you have room in your refrigerator, just put the whole vase of flowers in there until morning, then pop it out again for your breakfast table.
What kind of water is best for cut flowers?
In most cases, tap water is just fine, though not ideal. Some flowers don’t like the salt in softened water, some don’t like the fluoride, and high amounts of minerals can prevent absorption of the water up the stem. Because water travels more readily in slightly acidic water than in neutral water, flowers also do better in water that has a pH level of about 3.0 to 4.5. That preservative you sprinkled in the water will help with much of this.
When it comes to water temperature, the one-size-fits-all answer is to put your cut flowers in room-temperature, or lukewarm water. A more exacting answer is more complicated, of course. And apparently controversial.
Ariella Chezar, author of The Flower Workshop, suggests cold water for most flowers. The exceptions she cites are: rose or peony buds, lilacs, oriental lilies, and tightly closed flower heads that you’d like to open fully and more quickly.
On the other hand, Kelly Wilkiniss, author of My Soulful Home, A year in flowers, recommends warm water for most flowers. That’s because warm water molecules move faster than cold water molecules, she explains, so they reach the flower more quickly. The exceptions she cites are: chrysanthemums, orchids, tulips and other bulb flowers, which prefer cold water.
Special directions for special flowers
Flowers are unique, with unique needs, so while the guidelines apply to most, there are some exceptions to keep in mind. There are always exceptions, right? (As if you don’t already have enough to remember!)
Some plants ooze a sap when cut. These include daffodils, dahlias, hollyhocks, hyacinth, hydrangea, poppies, and tulips. To seal the stem, dip it in scalding water or burn the end with a match. The plants will still absorb water through the cell walls of the stems, just not from the bottom.
Flowers with hollow stems sometimes get air in the stems, which prevents the flow of water to the flower. To avoid this, fill the stems with water while holding the flower upside down over the sink. Then slide them into a vase of water. Flowers with hollow stems include: agapanthus, alliums, amaryllis, daffodils, gerbera, hollyhocks, larkspur, and lupines.
Did you notice that daffodils made both lists? While a splash of graceful yellow is a wonderful addition to an arrangement, don’t include daffodils with other flowers. Daffodils have both hollow stems and a sap that’s toxic to other flowers! Give those daffys a container of their own (they look beautiful displayed this way).
You may not remember all of these guidelines — or have the time to do them all conscientiously every time you’re lucky enough to have cut flowers in hand. Come back to this page when you need reminders, and do what you can, keeping in mind that helping your flowers to a good, fresh drink is your primary task. The reward of a lovely floral arrangement is well worth the effort!
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