Do Sub Domains go through a sandbox period?

I'm thinking of creating a directory subdomain for one of me niche websites.
Do you have to wait a few months for decent search engines rankings as if you were starting a new domain/website?

 

yes but to a lesser extent as the domain. page rank is given to sub domains from your domain.

 

Depends on value of your main domain. I mean if your main domain has PR6-7 and has multitude of indexed pages than your new subdomain will appear in SERPs much faster than a new domain and stay there for as long as your main domain stays, unless you overoptimize it or use other harmful techniuqes that will cause filtering or banning.

 

Thanks, pr4 main domain so might take a short while.
Patence is a virtue - so they say!!