1. Tulips are not easily portable.

This actually helps defeat the #3 argument, making Tulips more valuable than BitCoin, because it makes them rare and scarce. They are only grown while in season. BitCoins easy access and limited amount actually helps increase demand by those who want to run up the price.

And, while BitCoin can be carried on a piece of paper, there are limits to using it in the real world. You have to deal with someone who knows how to accept BitCoin. Similar to requiring a shipper who can handle shipping flowers over long distances. Not everyone is in that market.