Is that seriously your argument? Complex plants and beings have been proven to occur through evolution over millions of years. An organism may seem incredibly complex, so complex that there is no chance it could be spawned from the earth and not a creator, but this isn't so.
You might now think what are the chances of something, the human eye for example, evolving so perfectly to give us our uninterrupted view of the world. But its not like it just evolved all of a sudden. Over extended periods of time, bit by bit, it was built through evolution.
Look at it this way, its extremely unlikely that if you chucked some buckets of paint at the wall could create a masterpiece like the Mona Lisa. However, if you spend days, or in evolutions case, millions of years, slowly painting the different parts of the painting, you will eventually end up with an incredibly complex picture that would have first seemed impossible. Evolution works up, bit by bit, to create the complex organisms we know today.
By the way, the argument you proposed is known as Irredubile Complexity, the wiki link has some scientific responses to it on it :D
http://en.wikipedia.org/wiki/Irreducible_complexity