At dawn, flowers are filled with water and carbohydrates, so their stems are firm.
A few other tips for cutting flowers in your garden. Use a sharp knife or clippers – not kitchen shears, which crush stems, preventing water uptake. Cut on the bias for maximum water uptake.
Most important: immediately after cutting flower stems, put them quickly into a bucket of water. Stems denied water for even a short time can seal up. To prevent this some gardeners cut their flowers under water before transferring from bucket to vase.
Timing is important. Flowers will not open in water if cut too early. Flowers with multiple buds or spikes (salvias) or clusters (alstroemeria) should have at least one bud showing color, and one bud starting to open, before being cut. Flowers on individual stems (zinnias, dahlias) should be fully open before being cut.
I have run out of florist-supplied packets of flower preservatives. What can I make at home?
Cut flowers need three ingredients: carbohydrates for metabolism; something to kill bacteria; and a mild acid to adjust the pH of water in a direction that increases water uptake. Here is one effective home recipe: for each quart of water add
- 1 teaspoon sugar (carbohydrate)
- 1 teaspoon household bleach (anti-bacterial)
- 1 or 2 teaspoons lemon or lime juice (mild acid)
For a bouquet, is it true that dipping hydrangea stems in alum helps them last longer?
Yes. Find alum in the spices section of most grocery stores. Plan to cut hydrangea blooms in early morning while the weather is relatively cool. Drop stems into water immediately after cutting them (important). Later, while making your arrangement, recut the stems on the bias and dip the bottom half inch of the stem into powdered alum. Arrange as usual in water. (I know this washes off the alum, but it works!) One other way to prolong cut hydrangeas is to sear the end of each stem for 30 seconds in very hot water – or in a match flame for the same length of time.
Is it true that florists use lukewarm water, not cold?
YES! The only exception is for bulb-based flowers like tulips and hyacinths, which are coming out of cold earth. Warm or tepid water molecules move faster than cold water ones, and so reach up stems faster to get water and nutrients to the flowers as quickly as possible.