Space between subplots

If you want to pass the margins in the last command, I would recommend using a matrix (or row-vector in this case) to cover all subplots. Note that negative margins are allowed. AFAIK, a big limitation of Plots.jl is that all this is achieved by trial and error.

using Plots, Measures; gr()
plt1 = plot(rand(10))
plt2 = plot(rand(10); yformatter=_->"")
plt = plot(plt1, plt2, layout=(1,2), left_margin=[5mm -8mm])