It's probably not a huge surprise that I am enamored of flowers.  I'd be lying if I said that I love all flowers equally.  I'm not trying to knock anyone's appreciation of flowers and it bears saying that nothing beats flowers that you harvest from your own garden or that come from a local flower farmer.  Most flowers that are available for purchase (to consumers or florists) have been harvested at the best stage for longevity in shipping and transport.  This is a careful science and often involves some fairly advanced chemistry.  A huge number of these flowers are grown in countries where labor costs are extremely low (a real mixed bag for the foreign employees - nice to have a job but not so nice that so much of the profit from the industry goes to others) and environmental safety standards are also extremely low.  They can use chemicals on the flowers they wouldn't be able to use here.  Sometimes these flowers are given an extra fumigation to prevent insects from hitching a free ride along with the stems.  The entire picture is kind of impressive from an efficiency and operational standpoint!  
It's not what I'm looking for in a flower at all.  When I grow flowers I take great care with each seedling or bulb.  I don't harvest flowers at the first opportunity because I enjoy how the flower matures.  When I cut flowers to arrange for myself, I like flowers at their most full expression.  When harvested early, they never achieve this size or openness.  Something that I've observed over the years is that many of the flowers I grow actually sparkle in the sun.  A florist friend told me this is a result of the petals being fully hydrated.  Flowers are meant to shimmer!  I've never seen this on a flower at a store.  There is a range of color that petals can't approach when they've been harvested at the first opportunity, held in cold storage for weeks (the case for tulips, narcissus, and peonies), and transported through a variety of means before being available for purchase.  Sure, you can recut the stems and help freshen them up but it doesn't rejuvenate them to the same point a freshly cut mature bloom gets.  The picture above isn't the best from a photography perspective but it shows the sparkle of the tulip petals that I'm talking about.  No filter!  The glow of the petals is honestly how they look. 
As I've grown in my flower farming, I've also grown to appreciate the entire life cycle of the flowers.  I'm not yet to the stage where I harvest seeds (except accidentally in the case of things like Orlaya, celosia, cerinthe, and a few other self sowing wonders) but I have no doubt I'd be doing that if I had more space.  My favorite way to enjoy flowers these days is in the garden.  Cutting them for arrangements is a pleasure too but different than watching them interact with the wind and the bees and the sunlight.  That's part of why I am a very vocal advocate of growing your own.  Not everyone can do that, and I believe it's better to have any flowers than none at all.  If you are able to grow your own Just Do It! If you aren't, the next best thing is to support your most local flower farmer.  You will get the freshest blooms and they will enjoy your support.  

Given that my last post was a little bit of a rant against the idea that fresh flowers ought to last forever, I thought it was appropriate to explain some strategies to get your beautiful ephemeral flowers to last as long as they can.  Key ideas: water, location, and choosing the right stems. 

• Water - part of what makes flowers fade is that they can no longer keep pumping water up their stems.  In some cases this is because bacteria enter their transport system and clog it up.  Changing the water in your vase helps reduce the build up of bacteria in the water, gives your stems some clean water to imbibe, and gives your arrangement more time to look hydrated and fresh.  If you recut the stems an inch or so, that's every better! This provides the stem with a fresh opportunity to uptake water.  Make sure to cut at an angle to increase the absorptive surface.  
• Location - if your flowers are in a cool shady spot (always out of direct sunlight when possible) this also elongates their lifespan.  Heat makes molecules move faster (faster bacterial growth in the vase), makes water evaporate (out the vase) and transpire (out the stem) faster, and dries out the ambient air faster (increasing all that water movement).  No good for flowers that recently had their lifeline severed. Even if the plants want full sun, flowers never do!  If you have a cool fridge (no ripening veggies or fruit though as ethylene gas can make flowers fade FAST) and can put the arrangement inside overnight with PLENTY of water that will help.  That rule applies best to cool season flowers because if you have zinnias or basil stems in an arrangement cool fridge temps will make them wilt and brown.  
• Choosing the right stems - some flowers naturally have a longer vase life than others.  Hellebores picked at the mature stage will last weeks.  Pineapple Lily (Eucomis) stems will easily last a month!  Ranunculus, stock, and dianthus/carnations also have great longevity.  Other flowers just don't.  Icelandic poppies, dahlias, garden roses, and other much beloved stems just don't last very long.  These can still be fantastic for an event but if you get more than 4 days of vase life, consider yourself lucky.  

If you are getting an arrangement from a local grower it's helpful to let them know if you are going for "Wow" or longevity and they can choose stems better able to meet your wishes.  In the arrangement above, I purposefully chose some flowers that would last a long time (hellebores, ranunculus in the "marshmallow" stage, dianthus and stock), mixed with some "Wow" flowers (Iceland Poppies and some more open tulips) to keep the arrangement changing.  Don't be afraid to pull out flowers as they fade!  Let that also be a reminder to do a fresh cut and water change.  Enjoy your flowers! 

One of the issues that consumers have with fresh flowers is that of longevity. Everyone wants their flowers to last a long time.  I get it.  When you spend a pretty penny on something beautiful you want it to be around for a while.  Something you may not know is that there is a trade-off when you choose for longevity (sometimes several trade-offs).  Most flowers are cut before they are fully mature so the buyer gets to witness the unfolding of the bloom as part of the experience (and get longer vase life in the process).  If you let a flower mature in the ground or cut it only after it's fully open, it usually grows substantially larger than that same bloom cut three days prior.  So one trade-off for vase life is size.  
Size doesn't matter, you say?  Well, another trade-off for vase-life is fragrance.  At least in roses this is an issue.  Modern roses (especially the "florist roses") have been bred for longer vase life at the expense of fragrance. 
When I make an arrangement I try and include some big fully open WOW flowers (that will fade first) as well as a few that will slowly open in the vase.  As the first flowers fade, I would hope the recipient of the flowers will pull those to let the newly unfolding flowers take center stage.  The arrangements are meant to evolve and grow.  It's my way of bringing the beauty and ephemerality of the growing season and the life of the flower into focus.  When we tune in to the cycles of nature (which not only include, but absolutely depend on, cycles of decay) we need to make room for the whole picture.  Flowers are ephemeral.  That's part of their beauty.  It's also part of ours.  When we embrace all the cycles (and not just the young and sparkly bits) we get a more full experience of being alive.  
The above photos show tulips at the stage they *should* be cut (for longevity).  The right shows the same varieties fully open.  I love them both!