I've got 300 ladybugs in the refrigerator to hopefully help with aphids in the garden

The only question I have, (ok that's a lie, I have plenty) is do I leave them just under one bush or somehow spread them out.

I have been looking and I've even watched a Youtube video but he just stuck the ladybugs under a cardboard box under a bush. I have about 5-6 bushes that are infected out front.

Any suggestions would be greatly appreciated.