It not to late as I know deer will continue to utilize a good mineral lick well into the late summer, however the best time is indeed that late winter/early spring..... before the Doe start fawning. Be careful with your mineral mixtures as many of them are actually unhealthy for the animals. Unfortunetly it hasnt been legal to use minerals here in Illinios for many years so none of us can no longer do anything additional for our herds. [&:]