General Arrangement Care:

1. Keep flowers in a cool location with no direct sunlight. If the event is not for a few hours or the morning after, a clean well-working refrigerator can be the best storage space for some flowers.
2. If in a vase, change the water every day or every other day. This is by far the best step to keep your flowers alive for longer!!! Filtered water is best with a tiny drop of bleach and a bit of flower food. Make sure all the stems are submerged. Avoid foliage (leaves) in water- things can get gross if they stay in water (I think we're all familiar with farty flower smell...)
3. Cut an inch off stems at a 45 degree angle every 2-3 days so that flowers can last for over a week.
4. Do NOT leave in direct sunlight or in a hot area- also don't leave em right next to a fan or AC (cause of the force of the air being pushed out)
5. Be wary of pets- they get interested in plants sometimes for the wrong reasons! Note that quite a few varieties of flowers and foliage can be toxic to pets when ingested- so keep them away from prying paws!

Memory Mementos

In terms of drying your arrangements, some flowers will comply- and others are better off in the compost sadly.

Roses, tropicals, eucalyptus, and filler flowers dry the best. Flowers with delicate petals do not dry well- at all. (If you have dried flowers in your arrangements- you know they'll be ok- just be sure they don't go icky in the water)

Before the flowers wilt a lot, you can hang the bouquet or single stems upside down for a few days.

If you have boutonnieres/crowns/garlands, you can lay them flat to dry. Crowns can also be hung to dry and be kept as a wreath.

Water

Some flowers are more flower-loving than others. If you have lilies, hydrangeas, or dahlias in your arrangement be especially vigilant about the amount of water they have in their containers!

If your arrangement is in floral foam, you can add water (doing best to avoid pouring over the flowers) every other day. Once wilted, discard flowers in compost and foam in garbage, and be sure to reuse the container it was in.

Thorns & Turns

Some flowers/foliage come with specific smells, textures, and other oddities! For example, tulips can keep growing after they are cut, so they will tend to droop towards light. This can be fun and make an arrangement more unique- or it can be annoying! If you want to keep tulips from growing, drop an old copper penny in the water and keep them away from windows.

As we know with roses, some flowers come with thorns. I remove over 90% of thorns that may arise (literally).

Tropicals

If you have tropical flowers in your arrangements, DO NOT store them in the fridge or near an AC. Tropicals like room temperature the best!

Tropicals can handle some direct sunlight- but the flowers next to them may not so be sure to keep them in bright, indirect light.

Some tropical stems, like protea stems, are thicker than other flower stems, so you may not be able to cut the stems- which is fine since they last pretty long even without pruning (just be sure to change the water often).