I have just let it get dirty, they don't care. Their Idea of clean is still dirty for me. I see no reason why a place should not be kept spotless. All I have to say is one word to my landlord and I can have them out. He will tell me to handle however I want and he will back me up. He is a very very very patient landlord, I have been late by a whole month before on rent and he is just like "it's fine get it to me when you can". No way I would ever release spiders anywhere I am terrified!

I have known these guys since high school, that is the only reason I have put up with it for so long. I wouldn't want some people I have never met living with me. Thank you guys for the advice.
Oh trust me they used to never clean their own dishes, Then I flew off the handle and yelled at them, punched a hole in the wall and told them to get out or do their dishes. They started doing their dishes. I don't get that angry often, its hard for me to be angry.

It sounds like your landlord is easygoing and likes you. This is good, but it doesn't mean that he is looking for a fight. He may not want to threaten your housemates with eviction (assuming they are named on the lease), because this may open up a legal [censored]fight. And that's pretty exhausting (and expensive!). If your housemates are named on the lease, then as long as they are not
damaging the house, then it could be tough to evict them, even with your landlords support (but I also don't know what the tenancy laws are where you are). But the idea is that if your landlord warns them that they are breaching contract, they might just take the hint and move out.
On the other hand, as Xurts said, if you are named on the lease, and your housemates aren't, then you can easily have them kicked out. Legally, they are trespassing.
Another thing to consider is what sort of contract you are on. Are you currently in a fixed term contract, like 6 or 12 months? Or just month by month? If it's the latter, then just tell your landlord that you want him to not renew the periodic tenancy for your housemates, and you'll look for new housemates. The former (fixed term) is trickier---that's where the previous comments apply. But if you don't have too long to go on your contract, then maybe just svck it up for a little while, and then when the contract expires tell your landlord that you want him to not renew the tenancy for your housemates, and you'll look for new ones.
Failing all that, just move out. As I mentioned earlier, this is the most efficient and effective way to be rid of bad housemates (although it can be a bit of a lottery finding good housemates).
All that aside, one thing worth remembering is that dealing with housemates in this way can make the house relationships a bit toxic. So this is the sort of thing to do when you have decided that you aren't going to live with them any more, and either they or you are moving out. It's always better to sort things out without involving the landlord. But it sounds like your housemates aren't the sort to change their ways, unless you are constantly nagging them and making a big deal out of it---and of course that's exhausting, and I'm sure you don't want to have to do that.
Anyway, best of luck.