Good gardening friend Paul Parent of the Paul Parent Garden Club (http://www.paulparent.com/) sends out a great newsletter every week with pertinent gardening topics. I encourage you to go to his website to sign up for his newsletter. Paul can also be heard every Sunday morning from 6 AM to 10 AM at his website or at WBACH (104.7 FM) every Sunday morning from 6 AM to 9 AM. Paul recently sent this article out called How to Grow Onions (I have added a few comments in italics) and here it is:
"Onions are among the easiest vegetables to grow in your garden. Onions are one of the most useful vegetables you have in your kitchen and if you grow them yourself, you will not believe the flavor difference compared to supermarket onions. Your kitchen would not be complete without onions to flavor most everything you cook. This vegetable can be used in your salads, soups, stews, stuffing, sandwiches, and side dishes, and even eaten raw or cooked on your hamburger. The onion originated in Asia and was grown in all parts of the world by the Egyptians, Greeks, Romans and today you in your kitchen.
The onion comes in yellow, white and red. The shape will vary from round, oval, long, thin and will grow as a single bulb or come in clusters; some even grow out of the ground.
Select a spot in your garden that has sun all day long. Your soil should be rich in organic matter, so add plenty of compost or animal manure before planting every year. A soil that is loose and well drained without clay will grow the best plants. Never plant onions in the same place every year. Rotating crops in your garden will keep them healthier, especially if you keep onions away from same area for 3 years or more. Soil pH should be between 6 and 7.5. If soil is acidic, add lime. If you have a wood stove, sprinkle the wood ash on the ground before you till the soil to plant your onions.Onions have a terrible root system and have a tough time finding food far away from the plant. The same goes for moisture in the soil; it must be there, but not in large quantities. Water onions weekly, and keep the soil moist to a depth of 6 inches. If you use a fertilizer with Mycorrhizal fungi added to it, your plants will be able to grow a root system double the normal size and that means "BIGGER" and "BETTER" onions. Use all natural Garden Tone by Espoma or Plant Booster Plus by Organica. Use at the time of planting in early May and repeat 2 times more 4 weeks apart. A couple application of all natural Fish and Seawood Food by Neptune's Harvest will also help to push the onion plant to grow faster and larger.
I will catch "Hell" for this statement, but the best onion plants come from seedlings, not "BULBS". (We sell onions grow from seeds here at Skillin's and they grow HUGE!) Onion Sets are small onion bulbs grown in Holland and shipped to the Garden Center in a dormant state. These small onion bulbs are grown in a different climate and usually produce smaller onions in your garden because of climate change. I will guarantee you bigger onions, leeks, bunching onions, etc., when you plant seedlings. Some garden centers sell seedlings in flats or trays, or you can buy them in bunches of 100 plants out of the soil. If you choose bunches, prune roots by 1/4 inch and let them set in water for a hour or two before planting.
Plant onions 6 inches apart, and they will do best in wide rows of 6 to 10 plants in a row, rather than a single plant to a row. Weeds have always been a problem during the summer and if you are not careful, you will pull up the young seedlings with the weeds. This year look for a new product called "Weed Guard Plus" planting paper. Just roll it out on the soil and water it down. Now take a screwdriver and punch a hole in the paper to insert the seedling. Set the seedlings in the soil shallow and pinch the paper to move the soil around the plant. Once all your seedlings are planted, throw a little soil on the edges of the paper to help hold it down and water the paper down again. Once the paper gets wet it will stick to the soil and keep out ALL WEEDS. When your crop is ready to harvest, the paper will have already begun to decay into the soil. When the top of the onions begin to fall over, they are ready to harvest. Just pull them out of the ground and let them sit in the sun for a few days, or until the tops turn brown and dry up. Or you can also leave the onions in the garden until the top is brown and dried up. Store onions in your basement for the winter where it is cool but where they will not freeze. Enjoy."