Connie came back to the beach after four days and said "Gee, the
sunflowers are still ok". (Tho Bert, the cat, was sufficiently
enamored of them to knock over the vase twice in her absence

That makes it about a week since purchase...from a
long-shopped/respected farmstand.

Her feeling is that past sunflowers don't last long. These are cut to
8-10" stems, but her earlier ones were longer stems. Any relevance?

I can't believe it's the salt air Good genes? Why do some flowers
last, anyway?

-Brad

Sunflowers, properly harvested and cared for, can last up to 14 days
after cutting. The trick is to keep it alive and growing. This is
accomplished by feeding it and keeping sterile water in the vase. The
most common problem in cut flowers is drying out. Flowers take more
water than you might think.

The first thing is to cut the sunflower at the right stage of
development. The best time is when it's just opening. In this stage the
petals have started to unfold from the disk but haven't yet unfolded all
the way to be parallel to the disk. Cutting them young like this will
maximize the vase life.

As soon as you cut the sunflower, place it in water. The plant is trying
to feed the flower. To do this, it is sucking water and nutrients up the
stem. When you cut the stem, you get an air bubble, which prevents
further water from going up the stem. In your car, this is called vapor
lock. You can remedy this by cutting an inch or two off the stem later
while holding the stem in water.

When you get it into a vase, you need the right concoction to feed it
properly. Unfortunately, there's not a single mix of ingredients that is
right for all flowers. In general, the fluid in the stem is slightly
acid, so your vase water needs to be acidified. Citric acid is commonly
used, but in a pinch, vinegar can be substituted. Sterility is
important, since bacteria, once introduced into the stem, can multiply,
blocking the water passages. This starves the flower and causes
premature scenescence (the flower dies). The flower needs some
nutrients, also, so some sugar is commonly used. The optimum mix will
vary with the flower, but something like 1 quart of water, 1/2 teaspoon
of bleach (to sterilize it), and 2 tablespoons of vinegar should work
for sunflowers. For other flowers, you might add a tablespoon of sugar.

There is a website that gives post-harvest care requirements for common
cut flowers. http://chainoflifenetwork.com . To get to the requirements
page they want you to register, but it's free. I believe it also gives
information on the right stage of development to cut the flowers.


wrote:
Connie came back to the beach after four days and said "Gee, the
sunflowers are still ok". (Tho Bert, the cat, was sufficiently
enamored of them to knock over the vase twice in her absence

That makes it about a week since purchase...from a
long-shopped/respected farmstand.

Her feeling is that past sunflowers don't last long. These are cut to
8-10" stems, but her earlier ones were longer stems. Any relevance?

I can't believe it's the salt air Good genes? Why do some flowers
last, anyway?

-Brad