Starting onions from seed

ZBQ · March 16, 2007

How do you start onions from seed?

I have never done it and know absolutely nothing about it.

Thanks!

feldon30 · March 16, 2007

The "how" is you sow the seeds in seed starting mix in trays indoors under fluorescent lights.

It's the "when" that is the biggest question in tomato growing. Also the "which" is very useful since onion varieties are divided into long day, intermediate day, and short day. Sunup to Sundown is actually much longer in the North than in the South. Onions grow upward and thicken up until a critical night/day timing triggers the onion to start to "bulb". If you plant the wrong variety or at the wrong time, you will not get a bulb.

It would be helpful to know what your growing area/zone is, since your profile does not give Location or USDA Growing Zone.

TAMU PlantAnswers about Onions

In Houston, you can sow seeds for Texas 1015Y yellow onions on 10/15. The seedlings need to be thinned out to 4" spacing in February. Alternately, onion transplants become available in stores in January for planting in early February. This second option is the one I took.

ZBQ · March 16, 2007

I'm in southern Ohio. I think it is either zone 5 or 6.

I hope I didn't buy the wrong kind.

I bought these

http://rareseeds.com/seeds/Onion/Bianca-di-Maggio

http://rareseeds.com/seeds/Onion/Red-of-Florence

Am I too late to get these started?

feldon30 · March 16, 2007

Southern Ohio (Cincinnati, Portsmouth, and Ashland) is USDA Frost Zone 6a. I have seen estimated last frost dates (10% chance) of April 14th for your area. Based on that information, I don't know if seeds you start now will be ready and bulb in time. But I know very little about onions. I might ask a nursery when they intend to get onion starts (transplants). In Houston, if seeds are supposed to be started on October 15th to reach transplant size by January 30th, then that's 110 days just to get to transplant size.

Neither of those varieties you have mentioned from Baker Creek give any mention of day length, so that makes it hard to know when they can be planted.

The first one is a cipollini type onion which, in my experience, are harvested when they are 1-2 inches across, almost like large boiler onions. Cipollini onions do have a fantastic flavor.

Hopefully someone with more knowledge will chime in here.

pooklette · March 16, 2007

I am trying onions from seed for the first time this year as well so I'm afraid I won't be of much more help. I am in zone 5 and have been told that I have to grow long day varieties. I'm guessing the same could apply to you.

I did a Google search on the varieties you listed and according to the PDF version of Baker Creek's catalog, both are long day varieties.

feldon30 · March 17, 2007

DixondaleFarms.com, which is a great supplier of onion sets, has all of Ohio down as Long Day varieties.

ZBQ · March 17, 2007

Thanks guys, I knew I could count on you.

Looks like I will have to wait till next year to start my onion seeds.

I haven't noticed them putting out onion sets this year yet so I will just wait till then and buy some of those.

Thanks Feldon for the info and links! Helpful as always.8)

Ruth_10 · March 17, 2007

I am at about the same latitude as you near St. Louis. I start my onions the last week of Jan-first week of Feb. The seeds need only a bare covering (1/8th inch) with potting mix, then moisten. Onion seed is much shorter-lived than tomato seed. Plan on keeping onion seed no more than two years if you want good germination. My latitude (38.5 deg. North) is right about at the dividing line between long day and short day. Some catalogs will give latitudes ranges rather than just long day/short day, and that is the best guide to use. This year I am growing Copra (yellow onion, latitude range 38-55 deg.) and Ruby Ring (red, 35-50 deg. range).

Miss_Mudcat · March 19, 2007

I started onion from seeds for the first time last year. I start them indoors in either December or January by scattering the seeds in flats, cover with soil and water well. These are transplanted as soon as the weather breaks, which was just last week during that wonderful window of perfect weather we had.

Lisa

tjg911 · March 20, 2007

you are in the day long region. you can grow either day long or day neutral onions. if you are going to do this start immediately! i start mine on 2/22. i put mine out about 4/25. the goal is to have 5-6 weeks growth before planting out and then as much time as possible to grow as big a plant as possible before mid june. bulbing is triggered by the longest days in june.

how to start onions - put promix in container that's 1-2" deep. scatter or place seeds in rows 3/8" apart from each other in the row and the rows from each other row. i prefer to do the latter tho just sprinkling them on the promix works too. i wet the promix before putting the seeds in so when i cover them and mist/water the promix the seeds won't move. they come up in about 1 week, place under shop lights or in a full sun window. water as they dry out, fertilize with weak fertilier 2-3 times max before putting out, trim the greens when they are 4-5" tall back to 2-3".

onions are easy to grow, full sun, 1" water per week, don't compete well with weeds, fertilze just 1 time per month (may, june, july) and lose soil. come august when the tops start to lose their green color and some start to fall over, use a bow rake to gently push all the tops down, withhold water at this point, 1 week later pull them. for storage you have to cure them (if interested i'll describe) otherwise just store them in a cool place and eat.

sets are not worth the space, plants are ok seeds are the best. sweet (not hot) onions have thick necks and store just 2-4 months the hotter the onion the thinner the neck and the longer the storage.

tom

ZBQ · March 20, 2007

Thanks Tom!

I am definately interested in knowing how to cure them for storage. Going to have too many to eat all at once......hopefully!!

feldon30 · March 21, 2007

Well, you have a root cellar, right?

flowerpower · March 21, 2007

Tom, great info. This is the first yr I am growing from seed. I just started them the other day. A little late I see. Oh well, I was going to get sets anyway as a backup. I am just running out of what I had stored from last yr.

tjg911 · March 21, 2007

as mentioned the thick necked sweet onions only store 2-4 months while thin necked hotter onions store 6-12 months.

when you pull them leave them on the ground in the garden for 4-7 days, rain isn't an issue unless it rains the whole week! then move them to a shed, barn, garage, somewhere in the shade, out of the rain with some air circulation. i put them on racks i made from wood and chicken wire. just lay the onions on the racks using cinder blocks or saw horses to keep them off the ground. the bulbs can almost touch each other on the racks but i put the greens under the bulbs as i lay them on the racks. in 4-6 weeks they are cured. cut off the dried greens about 1" above the neck (NO water should be present, if there is use those 1st) and trim the roots to 1/2", store them in mesh bags at 37 degrees for best storage. initially in october i just put them into a 70 degree basement. as it cools i try to let in cold air at night or move them to a garage where it's cool. now they are in mesh bags in the garage where it's about 35 all the time. in a week or so i'll move them into the basement where it's 50-55.

it's that simple.

tom

michael johnson · March 22, 2007

The very best feed to give onion seedlings thro to half grown is (Nitro chalk) its perfect for them and all the champs use it over here in the uk,

The whole idea to get nice large onions- is to get as many leaves on them as possible, the more leaves the bigger the bulb.

I personaly like the big spanish onion type -mild and sweet.
cant stand these hot little spring bunching onions that burn your tongue off at the first bite.

Over here in the Uk most large onion seeds are sown just after christmas -when the day length just start to lengthen gradualy again, but later on around Aug/sept time we also sow another type of Japanese onion which are fairly large and tasty, which come into full growth around june the next season and just bridge the gap before the maincrop comes in.

March 16, 2007	#1
ZBQ Tomatovillian™ Join Date: Mar 2006 Location: Southern Ohio Posts: 170	Starting onions from seed How do you start onions from seed? I have never done it and know absolutely nothing about it. Thanks!

March 16, 2007	#2
feldon30 Tomatovillian™ Join Date: May 2006 Location: Rock Hill, SC Posts: 5,346	The "how" is you sow the seeds in seed starting mix in trays indoors under fluorescent lights. It's the "when" that is the biggest question in tomato growing. Also the "which" is very useful since onion varieties are divided into long day, intermediate day, and short day. Sunup to Sundown is actually much longer in the North than in the South. Onions grow upward and thicken up until a critical night/day timing triggers the onion to start to "bulb". If you plant the wrong variety or at the wrong time, you will not get a bulb. It would be helpful to know what your growing area/zone is, since your profile does not give Location or USDA Growing Zone. TAMU PlantAnswers about Onions In Houston, you can sow seeds for Texas 1015Y yellow onions on 10/15. The seedlings need to be thinned out to 4" spacing in February. Alternately, onion transplants become available in stores in January for planting in early February. This second option is the one I took. Last edited by feldon30; March 16, 2007 at 11:35 AM.

March 16, 2007	#4
feldon30 Tomatovillian™ Join Date: May 2006 Location: Rock Hill, SC Posts: 5,346	Southern Ohio (Cincinnati, Portsmouth, and Ashland) is USDA Frost Zone 6a. I have seen estimated last frost dates (10% chance) of April 14th for your area. Based on that information, I don't know if seeds you start now will be ready and bulb in time. But I know very little about onions. I might ask a nursery when they intend to get onion starts (transplants). In Houston, if seeds are supposed to be started on October 15th to reach transplant size by January 30th, then that's 110 days just to get to transplant size. Neither of those varieties you have mentioned from Baker Creek give any mention of day length, so that makes it hard to know when they can be planted. The first one is a cipollini type onion which, in my experience, are harvested when they are 1-2 inches across, almost like large boiler onions. Cipollini onions do have a fantastic flavor. Hopefully someone with more knowledge will chime in here. Last edited by feldon30; March 16, 2007 at 06:03 PM.

March 16, 2007	#5
pooklette Tomatovillian™ Join Date: Feb 2006 Location: Zone 5 Posts: 262	I am trying onions from seed for the first time this year as well so I'm afraid I won't be of much more help. I am in zone 5 and have been told that I have to grow long day varieties. I'm guessing the same could apply to you. I did a Google search on the varieties you listed and according to the PDF version of Baker Creek's catalog, both are long day varieties. Last edited by pooklette; March 16, 2007 at 11:21 PM.

March 17, 2007	#8
Ruth_10 Tomatovillian™ Join Date: Feb 2006 Location: MO z6a near St. Louis Posts: 1,349	I am at about the same latitude as you near St. Louis. I start my onions the last week of Jan-first week of Feb. The seeds need only a bare covering (1/8th inch) with potting mix, then moisten. Onion seed is much shorter-lived than tomato seed. Plan on keeping onion seed no more than two years if you want good germination. My latitude (38.5 deg. North) is right about at the dividing line between long day and short day. Some catalogs will give latitudes ranges rather than just long day/short day, and that is the best guide to use. This year I am growing Copra (yellow onion, latitude range 38-55 deg.) and Ruby Ring (red, 35-50 deg. range). __________________ --Ruth Some say the glass half-full. Others say the glass is half-empty. To an engineer, it’s twice as big as it needs to be.

March 19, 2007	#9
Miss_Mudcat Tomatovillian™ Join Date: Feb 2006 Location: Central Georgia Posts: 366	I started onion from seeds for the first time last year. I start them indoors in either December or January by scattering the seeds in flats, cover with soil and water well. These are transplanted as soon as the weather breaks, which was just last week during that wonderful window of perfect weather we had. Lisa __________________ Farmers don't wear watches; they work until the job is done!

March 20, 2007	#10
tjg911 Tomatovillian™ Join Date: Feb 2006 Location: zone 5b northwest connecticut Posts: 2,570	you are in the day long region. you can grow either day long or day neutral onions. if you are going to do this start immediately! i start mine on 2/22. i put mine out about 4/25. the goal is to have 5-6 weeks growth before planting out and then as much time as possible to grow as big a plant as possible before mid june. bulbing is triggered by the longest days in june. how to start onions - put promix in container that's 1-2" deep. scatter or place seeds in rows 3/8" apart from each other in the row and the rows from each other row. i prefer to do the latter tho just sprinkling them on the promix works too. i wet the promix before putting the seeds in so when i cover them and mist/water the promix the seeds won't move. they come up in about 1 week, place under shop lights or in a full sun window. water as they dry out, fertilize with weak fertilier 2-3 times max before putting out, trim the greens when they are 4-5" tall back to 2-3". onions are easy to grow, full sun, 1" water per week, don't compete well with weeds, fertilze just 1 time per month (may, june, july) and lose soil. come august when the tops start to lose their green color and some start to fall over, use a bow rake to gently push all the tops down, withhold water at this point, 1 week later pull them. for storage you have to cure them (if interested i'll describe) otherwise just store them in a cool place and eat. sets are not worth the space, plants are ok seeds are the best. sweet (not hot) onions have thick necks and store just 2-4 months the hotter the onion the thinner the neck and the longer the storage. tom

March 21, 2007	#12
feldon30 Tomatovillian™ Join Date: May 2006 Location: Rock Hill, SC Posts: 5,346	Well, you have a root cellar, right?

March 21, 2007	#13
flowerpower Tomatovillian™ Join Date: Dec 2006 Location: Catskill Mountains, NY Z5 Posts: 94	Tom, great info. This is the first yr I am growing from seed. I just started them the other day. A little late I see. Oh well, I was going to get sets anyway as a backup. I am just running out of what I had stored from last yr.

March 22, 2007	#15
michael johnson Tomatovillian™ Join Date: Jan 2006 Location: UK. Posts: 960	The very best feed to give onion seedlings thro to half grown is (Nitro chalk) its perfect for them and all the champs use it over here in the uk, The whole idea to get nice large onions- is to get as many leaves on them as possible, the more leaves the bigger the bulb. I personaly like the big spanish onion type -mild and sweet. cant stand these hot little spring bunching onions that burn your tongue off at the first bite. Over here in the Uk most large onion seeds are sown just after christmas -when the day length just start to lengthen gradualy again, but later on around Aug/sept time we also sow another type of Japanese onion which are fairly large and tasty, which come into full growth around june the next season and just bridge the gap before the maincrop comes in.