Good sanitation is the best defense against these little eating machines. Clear all plant debris from the vegetable beds (why didn't I make the time to do this?!!!!). Stir the soil around plant roots to expose eggs. Cover favorite plants (this would be all veggies!) with floating row cover--the best course after a new planting.
After they emerge, dust with diatomaceous earth or rotenone. On ornamentals try Sevin (carbaryl) or malathion. remember to follow directions. Any chemical can be dangerous. While carbaryl is considered safe for food crops, systemics like malathion are not.