\documentclass[border=3pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{lindenmayersystems}
\begin{document}
\begin{tikzpicture}
\draw[line width=1pt,green,rounded corners=4pt]
l-system
[l-system={
rule set={X -> X+YF+,Y->-FX-Y},
axiom=FX,
angle=90,
order=11,
step=10pt
}
];
\draw[line width=1pt,red,rounded corners=4pt, rotate=90]
l-system
[l-system={
rule set={X -> X+YF+,Y->-FX-Y},
axiom=FX,
angle=90,
order=11,
step=10pt
}
];
\draw[line width=1pt,blue,rounded corners=4pt, rotate=180]
l-system
[l-system={
rule set={X -> X+YF+,Y->-FX-Y},
axiom=FX,
angle=90,
order=11,
step=10pt
}
];
\draw[line width=1pt,orange,rounded corners=4pt, rotate=270]
l-system
[l-system={
rule set={X -> X+YF+,Y->-FX-Y},
axiom=FX,
angle=90,
order=11,
step=10pt
}
];
\end{tikzpicture}
\end{document}
