Hi! I'm new to this forum & hope someone can help me! My sister & I started growing dahlias last year & fell in love with them! We each have about 25 varieties this year. My sister is growing hers exclusively in pots. She called me yesterday very upset. She checked her dahlias in the morning & they all looked great. Then about 6 hours later she checked on them again & one of her Thomas Edison plants was knocked completely over. It got a late start, so it was only about 6" tall. She dug it up & saw that the tuber was completely hollow. It was not rotten. She said squeezed & it was just empty. There was no liquid or mushiness to it. The plant was growing normal right up until it fell over (although it took much longer for a bud to sprout). Does anyone know what could have caused this? Could it be insects?