Do not mix Daffodils
Daffodils should not be mixed with other flowers in a vase.
Cut daffodils release a stem-clogging sap (slime exudate) that causes other flowers to wilt especially tulips. Cut them early in the morning when they are barely opened and place them in a bucket of luke warm water for several hours. Add 1 teaspoon of sugar to quart of water to preserve freshness. Wait at least 12 hours after cutting before combining them with other flowers this allows time for the sap to leach out. Do not recut them when arranging with other flowers. They should last 4-6 days depending on temperature exposure.
Recent studies have shown that floral preservative should not be added to cut tulips. It shortens their longevity by clogging the stem causing them to wilt.