minature sunflowers

I bought a minature sunflower 3 lovely flowers and a lot of buds on it. Could someone please tell me what has eaten all the leaves and why the buds have all withered? I keep it well watered, lots of tlc

 

I had one last year, it did well for a while then suddenly started going poorly, I never did find out why :(

 

thanks jay, I'm just going to collect the seeds and try again next year!! 'If at first you don't succeed'!

 

? too much water. I tend to neglect mine once they are in the ground and they have been good and strong this year despite 4 weeks of drought.

 

that could be it badsal72. I have them in a pot at the front door and they get a daily watering. Don't know what ate the leaves tho. thanks