About 7 years ago we planted onions with a mechanical planter pulled behind a tractor with a hydro static transmission. This type of tractor can go creepy crawly slow. You can crawl faster than the tractor's ground speed. This is just what the doctor ordered when planting transplants. However this tractor is very heavy an d caused soil compaction on wet spring soils so I don't use it anymore.
We now plant onions by hand. It takes three people a little over and hour to plant several thousand plants. We plant about 15,000 onions and leek plants per season. The process takes several weeks.
This year we are getting a very late start.
The onions need to be very well established by May when the day length requirements are met and they start to enlarge. It is just amazing how quickly the onions explode in size when we reach June. They go from the size of your thumb to softball size in a matter of weeks. Very cool.
We till the soil, fertilize lightly with organic fertilizer and then I lay down a strip of compost 12 inches wide and 3-4 inches deep. It takes about 2000 lbs of compost to make a row 300-400 feet long. We will create about 10 rows like this for our onion crop this year. If this seems like a lot of work and copious amounts of compost, it is!
Why do we plant this way?
- Onions are very sensitive to weeds and don't compete very well. The compost creates a weed barrier to keep weeds out of the rows. We weed lightly every 2-3 weeks during the season and the onions are nearly weed free.
- I'd rather scoop a little compost, well, OK, A Lot of Compost, than weed.
- The flavor of onions grown this way is out of this world. They are sweeter and the storage quality is amazing.
- The flavor is better because of the minerals and organic components in the compost. The compost feeds the life in the soil. When we pick onions, we find significant quantities of earth worms around the roots.
- Did you know that the plants "talk" to the organisms around their roots. They give off sugar exudates which attract the bacteria and fungi that will convert nutrients to the form the plants need. This is what attracts the earth worms. They are there cleaning up the root zone and eating the left overs.
- Onions are light feeders and you can almost get by with just compost and earthworms for fertility. But if you want jumbo onions they need a littl starter fertilizer and a booster shot of fish emulsion before the onions start to enlarge in June.