I personally try to call unless there are already plans setup. I need to improve in texting, I guess for whatever reason I text needy but on the phone they seem to get really into me. Guess it's my voice, plus it puts them on the defensive like they need to perform and in that state of mind they are trying to get me to like them, which I want...more hand early on. Texting imo and in my experience for me (..not sayin everyone) is so impersonal and gives the girl the choosing power. On the phone I can find out more about her and see if I get a good vibe from her before deciding whether or not I'm going to put out the effort to get together with her, rush to get ready, brush my teeth, wash my car, make sure my place is immaculate etc. etc. etc. there is a lot of energy that goes into going out so best to know for sure you would want to invest that energy into this girl (p.s. buyers frame fo shizzle)
So for me, I'll call at a time I think she's most likely available. If she doesn't pick up, I just hang up. No message (she'll know it's me though because my name will be on her phone), and try again a couple days later. After a few tries no answer she is telling you she isn't interested. With texting there is no taking back words you wrote that may not come off too well (if you aren't great at getting the other person interested in responding and maintaining your masculine essence in the process) and 1 perceived bad text and all her girlfriends will get to see it and judge it..... for me that's a losing game. I remember just recently seeing this chick I used to date go to the trouble of posting a facebook picture of a guy that text her something stupid so all her friends could laugh at it. I removed her as a friend (I don't want to associate with girls like that) and that put the nail in the coffin on texting for me..... can do it, but under special circumstances (like I KNOW she's super into me and all I need to do is name the time and the place).
Luck