Onion growing tips?

Onion growing tips?

I am about to embark on my 2nd try at growing onions. This year, I've bought burgermaster. Last year, I tried growing them in my regular garden (Walla Wallas) and it took an extremely long time to grow and then they started to rot when they were very tiny. I was thinking about maybe trying to grow some in deep planters this time. I'd read somewhere that adding a little bit of sand into the soil is good for onions. Any opinions on this? Any other tips?
Mulberry cuttings.

Mulberry cuttings.

tulips

tulips

Holy Crap! What the …

Holy Crap! What the …

garden pron!!!

garden pron!!!

Plant ID Please

Plant ID Please

Tadpoles

Tadpoles