Pathetic spring onion

I sowed the bulbs on 17 March and today is 6 April - more than 20 days! Pathetic 4 sprouted. I sowed more than 15 bulbs in total... sigh.. I thought they are easy to grow... maybe it is too wet as it has been raining everyday for the past weeks and every time it rains, the whole styrofoam box will be flooded....