Onions are a staple of most gardens, and there are a few tricks to ensure a good harvest. Water frequently because they have shallow roots. Never let them dry out during the bulbing stage or they will be small and leathery, and you will also have less insect issues if they are kept moist. Also, keep your patch weed-free because of their shallow roots. They don't compete well.


One of biggest keys to success in organic gardening is the condition of the soil. There needs to be adequate organic matter to hold moisture and nutrients. And at the same time, the soil needs to be loose enough for good aeration and drainage, which will help promote strong root development.

It is easy to grow onions if your soil has the proper nutrients. People always assume their soil is average, but unless you have a soil test it is just a guess. More often than not, it is necessary to amend the soil to achieve optimum pH balances, as well as the proper levels of nitrogen, phosphorus and potash. Testing your soil is ideal; however, at a bare minimum, before planting anything, work in at least 2-4” of organic mulch (or up to 6” if you have clay soil) and at least one-half inch of finished compost into your topsoil. Onions grow best in rich roil that’s well drained. If you suspect your soil is less than ideal, mix in a cup of MegaVeggie if you feel your soil is in great condition, 2 cups if in good condition and 3 cups if in poor condition, into every 100 sq. ft. of soil. This 100% organic soil amendment will make up for a lot of deficiencies.

Also, mulching with compost or straw will help keep the soil moist and also help to feed the plant and prevent weeds. Don't mulch over 3-4" because this might prevent oxygen from entering the soil and could cause root rot.


Onions should be planted as soon as soil can be worked and the hard freeze season is over. Onions are cold tolerant, but a freeze will damage small onions. Plant seed about 1" deep in rich soil, then water with seaweed solution. This will help germination and promote root growth. Space 1/2" apart in rows, and when onions have about 10 leaves, thin to 3-4" apart. Keep rows 12" apart, or if you are planting in raised beds, plant 4-5" on center.  If you are starting with onion sets instead of seed, plant 4-5" on center.


After planting, continue to feed seaweed (MegaSea) once a week by spraying leaves. The seaweed will really help the sweet varieties be extra-sweet. Also, apply hydrolyzed fish (MegaFish) every two weeks through root feeding until harvest. I use a hose sprayer for fish, but just make sure you spray enough so that the roots of the plants are soaked. If fish gets on the leaves, don’t worry, it won’t burn the leaves.

Onions require an ample supply of nitrogen, so a couple months before harvest, side dress with MegaVeggie again, or with Rooster Poop or Bird Guano. If your plants are not vigorous, they are not getting enough food and your soil must not be in great condition. In that case, continue to side dress with 2 tablespoons of MegaVeggie around the base of the plants and water in. Continue MegaSea once a week along with MegaFish every two weeks. Do not let the soil dry out; soil should be moist but not soggy.

Recommended Schedule for Fertilizing and Amending Soil:
1. MegaSea seaweed -- at planting and once a week until harvest
2. MegaFish hydrolyzed fish -- every two weeks after planting until harvest
3. MegaVeggie – at planting, and a couple months before harvest. If plants do not appear vigorous, then side-dress every two weeks until harvest


When onions are about ready to harvest, the tops will begin to lay over, and when half of them are falling over on their own take the back of a garden rake and push the others over. Try to do this all in same direction. Stop watering at this point, leave them for a week in the soil, then pull and lay them on their side so the sun can dry one side of bulb. When they are dry on that side (about a week usually), flip them over to dry the other side. Hang up in a cool dry spot and don't remove leaves until the leaves are completely dry. If you want, you can do what I do: I leave on the leaves and braid them because I store in an outside room. Either way, if you leave dirt on their roots they will think they are still in the ground and will keep much longer. Remember, the big sweet variety won't keep as long as the regular yellow storage onion, so eat these first. I make onion soup when i feel they are going to turn.

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