ive seen T and scorpions later than between 4-7..if your talking PM, ive seen them after 11PM into 1AM sometimes. You dont need grass for them to show, just your gate closed. And dont have your net out, if you do, youre sure to get bitten. Just walk around or do your usual stuff, and when u see one, try to get behind it and follow it closely, then when youre sure u can net it, quickly take net out and go for it.