Changing the labels on ggplot legend - r

Question

I'm using ggplot so I can get a gradient onto a map to show data over a large scale. There are points between 0 and 35,000 to be visualised. I have got this to work, but the legend is automatically showing labels for every 10,000.
Ideally I want the legend to show the maximum amount, so probably it would just show 0 at the bottom and 35,000 at the top. Is this doable?
My ggplot code is below if this helps.
ggplot() +
geom_map(data = datafile, aes(map_id = Health_Board, fill = datafile$"2007"), map = Scot) +
geom_polygon(data = Scot, aes(x = long, y = lat, group = group), colour = "gray", fill = NA) +
expand_limits(x = Scot$long, y = Scot$lat) +
scale_fill_gradient(low = ("lightyellow"), high = ("red"), limits = c(0,35000)) +
ggtitle("2007") +
coord_fixed(1.2) +
theme(axis.text.x = element_blank(), axis.text.y = element_blank(),
axis.ticks = element_blank(), axis.title.x = element_blank(),
axis.title.y = element_blank(),
panel.grid.major = element_blank(), panel.grid.minor = element_blank(),
panel.border = element_blank(), panel.background = element_blank(),
legend.title = element_text(face = "bold"),
plot.title = element_text(face = "bold", hjust = 0.5))

Answer 1

You can include the "breaks" argument. Like this:
scale_fill_gradient(low = ("lightyellow"), high = ("red"),
breaks=c(min(lat),max(lat)),
limits = c(0,35000)) +
If you want more, its possible to include the "labels" argument.
scale_fill_gradient(low = ("lightyellow"), high = ("red"),
breaks=c(min(lat),max(lat)),
labels=c("Minimum","Maximum"),
limits = c(0,35000)) +