However, I have been doing some research on "siloing" and I have discovered that, from an SEO standpoint, it is better to keep the services I provide on separate domains even though they are in the same industry and all very closely related. The argument goes that if I provide all of these services on one site it will dilute the "authority" (in the sense of "focus") of the site.
To give you a completely imaginary example, let's say I own potatoes-service.com, carrots-service.com, onions-service.com and stew-service.com. Although they are closely related, they are definitely separate services that could survive and flourish on their own they are also all part of the "stew-making industry". Potatoes-service.com has grown to become a big player in its service field and I want to incorporate all of these services on my potatoes-service.com site.
The questions is: Is it better to keep them separate on their own specifically related domain name with the exact service they provide included in the domain name? Or is it better to take advantage of the traffic at the well established orangeservice.com domain name while taking the chance that it might lower my ranking all across the board because it dilutes the overall theme or "silo"?
Also, if I do keep them on their separate keyword related domains, can I link them from my main business of potatoes-service.com? Will Google penalize me for linking my sites together? I don't quite see why they would do that when I have never hidden the fact that these are all my sites and that they are directly connected. In fact, I advertise them that way. However, others have said I should be careful about linking my own sites together. Why? What is Google's reasoning here? Why would Google, in effect, put limits on the number and type of businesses I own?
Any and all input -- whether its scoffing, debunking or clarification -- is appreciated.