Matthew, What kind of onions are you growing? Sounds like you fertilized them quite well when you planted. Let them get a good start and you can always use a fish emulsion foliar spray as they grow thru out the season. I have used this for several years with good results.

I read that onions migght benefit from (21-0-0 - Ammonium sulfate or Ammonium nitrate) becuase they like lots of nitorgen? Your thoughts on that?

They do like lots of nitrogen, however, I have never used ammonium sulfate or nitrate so I can't answer your question. I usually try to use organics when I can, though I am not opposed to commmercial fertilizers. It's difficult to answer your question not knowing your growing conditions and how much 10-10-10 you gave them at planting. I'd wait and see how they do before I added any more fertilizer. Maybe someone else can give you a better answer.

I watered with Miracle Grow a few days ago. It has decent nitrogen 24% concentration. Has anyone else used MG successfully on onions before?

Watering: Onions need moist soil;(that is their root) Because onions are planted almost on the surface, the roots are not going to be deep. THEREFORE, they need more frequent watering. Good mulching can help.
Fertilizing: It depends onwhat kind of garden soil you have. MOST established gardens have sufficient amount of P and K. Because, unlike N, they stick around much longer. That is why, all you have to add(as fertilizer) is "N"itrogen.

This is my first year growing onions as well. I didn't fertilize them much before planting out. The raised bed garden is new (great topsoil, compost, well composted manure, minimal green sand and azomite) and the plants look very healthy. How often should they be fertilized with the fish emulsion?

Also, what do you sue for mulch?

Most of my onions I have what look like healthy green shouts that are standing upright..about a ft. A few are starting to flop over. Is that normal? WE have ahd plenty of rain so I dont think they need water. Thoughts?

Sorry about that last post of gibberish. Basically I want to know if onions flopping over is normal..especially at this early in the season.

matthew - this is my first year with onions/garlic planting that I hope I did all correctly. Mine are in raised bed. I fertilized them monthly since Jan - with N - foliar spray of seeweed and granular additions to the soil. But I would not give them any more fert now - they need to stop growing green and instead enlarge the bulbs. The green tops are 1ft tall then flop down and another 1 ft long (touching the ground). Some started to put on flower head which I cut off. We were getting plenty of rain lately so I dont think I need to water them either - just let them go though the process and hopefully harvest next month

This advice may come a little late, but...The practice called "banding fertilizer" -- placing it beneath the plants, right where the roots will find it -- works great with onions. They get a heavy feed early on, leading to lots of leaves, and then run out of food as they size up. A lean nutrient supply at maturity leads to sweeter bulbs that store better.

We have had a great deal of rain in the Albany/Saratoga area for weeks now. Most of the leaves are at least 12 inchs tall. Most are standing right up. Some are starting to flop over. Is that normal and ok?

Matthew No it's not normal for the whole top to fall over in may in zone 5 BUT a few of the out side leaves will fall over But stay green. You say your planting SETS imo they are a poor choice unless you just want green onions.If you want large bulbs imo you should be planting long day onion plants.If you would google [onion plants] you find more information than I can give you here.I find it odd that a person in zone 8 knows what kind of fertilizer your soil in N.Y.needs? GOOD LUCK TO YA!!! YOPPER