Q.Do Double Tulips Perform Well With Annual Flowering Or Are They Prone To Rapid Exhaustion?
How can I get more longevity and annual ‘staying power’from double tulips other than leaving foliage to completely die back,regular fertilizing and providing similar growing conditions to those found in the tulip’s origin geography.
Certified GKH Gardening Expert
If you haven't already, try using a fertilizer that's designed especially for bulbs. It sounds like you're doing everything right - the flowers have a certain life cycle they will complete no matter what. Another possibility is proper watering. Here's an article that may help: https://www.gardeningknowhow.com/ornamental/bulbs/tulips/watering-tulip-bulbs.htm
To extend the season, you can plant tulips that bloom early, mid season and late.