Hi emorway, You are right. I tried the command only with one year's data, in which case it plots month names as labels. But for multiple years, the labels become years. I found this old post useful - http://n4.nabble.com/Month-tick-marks-on-a-plot-td879121.html#a879121. Picking the code from the comment by Gavin Simson, I think this should work:
plot(as.Date(cropped.cast1$date,"%Y-%m-%d"),cropped.cast1$Frac_ET_Satsfd_mean,xaxt="n") x<-as.Date(cropped.cast1$date,"%Y-%m-%d") ticks.at <- seq(min(x), max(x), by = "months") ## format the labels as abbreviated month names ticks.lab <- format(ticks.at, format = "%b") ## indicator variable; is month January? m1 <- ticks.lab == "Jan" ## plot small ticks and labels for months not Jan Axis(x, at = ticks.at[!m1], side = 1, labels = ticks.lab[!m1], las = 2, cex.axis = 0.7) ## plot the default tick locations for years Axis(x, side = 1, las = 2) ## add the box box() ----- Try http://prettygraph.com Pretty Graph , the easiest way to make R-powered graphs on the web. -- View this message in context: http://n4.nabble.com/adding-infrequent-date-labels-to-x-axis-tp1564804p1564924.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.