Can you cold stratify seeds for too long? (Updated with my results!)

Blueberry Acres

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I was planning on growing some pansies for fall color. I bought a seed packet last summer and stuck the packet in the refrigerator drawer... then completely forgot about them until last November. Whoops.
:hide

They are still in there. Do you all think I can still start the seeds indoors for a "spring crop" of pansies? Or were they cold stratified too much?
 

flowerbug

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if they were taken out of the packet and put in something and moistened and then put in the fridge then yes if you left those too long it may no longer work, but if they are still in the seed packet then i don't think you've harmed them by doing that as long as they weren't wet.

if you open the packet and they aren't rotten or rotting i think you will be ok, but also, it really doesn't hurt to try. :)
 

heirloomgal

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I was planning on growing some pansies for fall color. I bought a seed packet last summer and stuck the packet in the refrigerator drawer... then completely forgot about them until last November. Whoops.
:hide

They are still in there. Do you all think I can still start the seeds indoors for a "spring crop" of pansies? Or were they cold stratified too much?
I would give them a try @Blueberry Acres. The cold stratification is more about having the seed experience a distinct transition from cold to warm, to genetically trigger it into thinking it's spring. It's not so much about duration of the 'winter' cold spell. Some seeds, like morning glory seeds, can go through a long, cold period multiple times before getting triggered to sprout and still grow just wonderfully.
 

Blueberry Acres

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if they were taken out of the packet and put in something and moistened and then put in the fridge then yes if you left those too long it may no longer work, but if they are still in the seed packet then i don't think you've harmed them by doing that as long as they weren't wet.

if you open the packet and they aren't rotten or rotting i think you will be ok, but also, it really doesn't hurt to try. :)
I would give them a try @Blueberry Acres. The cold stratification is more about having the seed experience a distinct transition from cold to warm, to genetically trigger it into thinking it's spring. It's not so much about duration of the 'winter' cold spell. Some seeds, like morning glory seeds, can go through a long, cold period multiple times before getting triggered to sprout and still grow just wonderfully.
Ok, I will give them a try (I'll try to give an update of my results, too!)

Thank you both for your help! :frow
 

Blueberry Acres

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I store all of my pansy seed packets in a ziploc bag in the freezer. They have been there for 1-3 years, depending on when I bought them. 'Cool Flower' seeds like feeling the cold. They are slow growers though, with up to 12 weeks from seed to bloom. I just love them! 🌸
Wow! Do you find freezing them helps keep them fresh? Now that I think about it, I read an article on storing seeds long-term, it said something about chilling them.

I've got a lot of dry seeds in packets in my living room. I wish I had frozen them now 😕
Depending on when the expiration date is (which is not necessarily what you should go by, seeds may last a long time after that date), and how the seeds were stored, they may actually still be viable.
Seed-Viability-Shelf-Life-Chart-homestead-chill.jpg

 

digitS'

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That vegetable viability chart agrees quite well with what Iowa State University has out there LINK.

I have never frozen seed but have learned to follow a "less than 5 years" benchmark for tomatoes and some other things.

We need to be thinking about seed for garden starts in January. I will sow onion seed in the (unheated) greenhouse in about 3 weeks and pansies about then, also. Pansies grow slowly and yet, they can be set out early for Early Season blooming.

Steve
 

ducks4you

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You might try using a small baggie and a moist paper towel. Put 10 seeds in the paper towl and fold it over. Place it inside of the bag, leave it on of your fridge for a week, then see how many have sprouted. This will give you the % of seed viability.
I hardly think they are damaged bc places that keep very rare plant seeds keep them supercooled in nitrogen.
Please, let us know what happens! :hugs
 

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