  The classical Hadwiger conjecture dating back to 1940's states that any graph
of chromatic number at least $r$ has the clique of order $r$ as a minor.
Hadwiger's conjecture is an example of a well studied class of problems asking
how large a clique minor one can guarantee in a graph with certain
restrictions. One problem of this type asks what is the largest size of a
clique minor in a graph on $n$ vertices of independence number $\alpha(G)$ at
most $r$. If true Hadwiger's conjecture would imply the existence of a clique
minor of order $n/\alpha(G)$. Results of Kuhn and Osthus and Krivelevich and
Sudakov imply that if one assumes in addition that $G$ is $H$-free for some
bipartite graph $H$ then one can find a polynomially larger clique minor. This
has recently been extended to triangle free graphs by Dvo\v{r}\'ak and
Yepremyan, answering a question of Norin. We complete the picture and show that
the same is true for arbitrary graph $H$, answering a question of Dvo\v{r}\'ak
and Yepremyan. In particular, we show that any $K_s$-free graph has a clique
minor of order $c_s(n/\alpha(G))^{1+\frac{1}{10(s-2) }}$, for some constant
$c_s$ depending only on $s$. The exponent in this result is tight up to a
constant factor in front of the $\frac{1}{s-2}$ term.
