How To Grow Onions

ING-onions_sql Onions

Please see individual varieties for specific product information, but in general the growing information will be the same for all melons including cantaloupes and honeydews. The majority of the information on this page was provided by the University of Arkansas Cooperative Extension Service Onion Home Gardening Series; download the complete pdf file with FAQ’s for more information or click here to visit the website.

Average Days To Maturity: 100 to 120

Distance Between Rows: 2 feet

Spacing Between Plants: 4 inches

When To Plant: For spring planting it is recommended that you use sets, seeds or transplants as soon as the weather warms.  If planted too early damage could occur.  Seeds can be started inside 8 weeks before planting in the field.  Plant fall onion sets in late October or early November.

Planting Tip: Different varieties of onions require different amounts of sunlight.  If your onion is listed as long day, then it requires 15-16 hours of daylight.  If it is listed as short day, then it needs around 12 hours of daylight.

Average Yield: About 10 to 15 pounds for a 10 foot row, which is the recommended amount to grow per person.

Preparation and Care: When preparing the soil, add 4-5 pounds of 10-10-10 per 100 square feet.  Onions are heavy oniongreen feeders so prepare to feed them again in about 3 weeks and again when the bulbs start getting big.

Bulbs have shallow root systems which do not mix well with weeds so keep the weeds away.  Onions prefer shallow cultivation so leave the mounds for squash and cucumbers and only cover your onions with 1-2 inches of dirt.

Watering: Water your garden (cantaloupes and everything else) once a week with a 8-12 hour soaking. This will allow the soil to absorb an adequate amount of water and also limit the time you spend each week watering.  If you use a sprinkler to water, do this during the day so that the plants will have some time in the evening to dry out before dark. This will limit the chances of disease. If you use a soaker hose, you can water at night. Watering with a soaker hose at night is best as it limits the amount of water lost to evaporation and keeps the plants dry which limits the chances of disease. During dry periods you may need to water more often (every 4-5 days), and watering at night is important in water conservation during droughts.

Fertilize: After your onions have been planted for about 3 weeks, sprinkle the row with 11/2 to 2 tablespoons of ammonium nitrate per 10 feet of row.  Do this again when the bulbs begin to enlarge.

Harvesting: If you are harvesting green onions, let the tops get about 6 inches tall.  If you planted bulb onions, pull them when about 2/3 of the tops have fallen over.  Do not wait more than a week or two after this happens to harvest.  If it is going to be dry for a while, then you can pull the onions and allow them to dry in the field for a few days.

To cure onions, place them in a well ventilated attic or porch area out of the sun for a week or two.  When storing leave about one inch of the top on.  The better the onion is cured, the longer it will store.  You can also store onions in old panty hose.  Drop one onion in and then tie a knot before placing another in and repeat.  You can then hang them from the rafters in your storage area.

Culture Problems: Be careful when handling, bruising can lead to rot.  If you do not dry them properly they could also rot.  Make sure that you do not let onions dry out when they are developing, this could cause them to split or develop double bulbs.  Small bulbs can also occur from late planting and too little water.

Common Insect Problems

Common Disease Problems

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