stratifying in the south...

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philip_la
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stratifying in the south...

Post: # 68762Post philip_la
Fri Dec 14, 2018 11:07 am

Just curious as to the methods others use. My fridge stays on a pretty cold setting -- colder than would be recommended for stratifying and/or callousing cuttings -- and with the idiosyncrasies of a fridge, I have occasionally had a seedling sprout and then freeze.

While it's not in the budget for us to get a dedicated fridge (I suppose it could double as a wine cellar?) I wondered if others go that route. The settings don't normally permit temps higher than about 40 deg. farenheit, but digital temp controllers can be found for under $30.

Do others go that route?
Philip F.
[size=small][color=#669966]Zone 8 / Sunset Zn 30 (Austin, TX -- formerly New Orleans, LA)[/color][/size]

henry kuska
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Re: stratifying in the south...

Post: # 68763Post henry kuska
Fri Dec 14, 2018 1:55 pm

I was able to purchase a working college dorm size refrigerator at a flea market for very little money.

philip_la
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Re: stratifying in the south...

Post: # 68766Post philip_la
Fri Dec 14, 2018 8:12 pm

Doing a little research on such, came across this thread (for brewers who need a consistent temp for brewing): https://www.homebrewtalk.com/forum/thre ... 5f.401960/
The same approach could be used for the *really* serious hybridizer with a moderate budget for such.

What is the "best" temperature for stratifying the average seedling? And do species from colder climates require colder temps? I've had pretty good luck in my "too cold" fridge with species that really don't stand a snowball's chance in Hades down here (nitida, rugosa, etc.). And is the ideal callousing temp for semi-ripe cuttings comparable, as I'm thinking?
Philip F.
[size=small][color=#669966]Zone 8 / Sunset Zn 30 (Austin, TX -- formerly New Orleans, LA)[/color][/size]

roseseek
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Location: Zone 9b Central California, Sunset Zone 15
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Re: stratifying in the south...

Post: # 68775Post roseseek
Sat Dec 15, 2018 12:40 pm

Until it became an issue, I kept them in a larger ziploc bag in the vegetable crisper. Back in the old, hotter climate, I had one of the small fridges usually available for about a hundred bucks. Here, I don't bother "cold stratifying" anything and I raise far too many seedlings to comfortably handle. But, I'm also not using anything for "Arctic hardiness", either.
Kim
California Central Coast
USDA Zone 9b
Sunset Zone 15
Cooler inland coastal valley with strong marine influence

jbergeson
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Re: stratifying in the south...

Post: # 68776Post jbergeson
Sat Dec 15, 2018 4:43 pm

I think cold fridge temps are fine for providing cold stratification. After several months you could start bringing the bag out for some hours every day to stimulate germination, or just sow all the seeds.

Plazbo
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Re: stratifying in the south...

Post: # 68778Post Plazbo
Sat Dec 15, 2018 6:50 pm

I'm in a similar boat to Kim, don't cold stratify and haven't found the need to, being in Sydney Australia, not too far from the coast there's minimal chance of sleet, let alone freezes or snow. I just collect the seed, pot them up and leave them outside. While germination rates with rugosa derivatives are likely reduced, I do get germination which will likely improve as generations move forward. I kind of see the need to stratify as the first culling/to be selected against.

philip_la
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Re: stratifying in the south...

Post: # 68788Post philip_la
Mon Dec 17, 2018 12:35 pm

My current M.O. is to cold stratify in tiny zip-lock baggies for about 2 months, and then leave out about 2 weeks. Species like rugosa and nitida will have done nothing still at that stage, and often I have limited germinations from other hybrids, so thereafter I usually do another 2 weeks in and a few days out, over and over again until, like popping popcorn, I decide it's time to throw in the towel. But hope blooms eternal, and for some roses, I don't give up when I clearly should. Another downside is that I sometimes find germinated seed that appear to have frozen.

I think this M.O. is actually deleterious to warmer species hybrids as I've had much poorer results than anticipated from seeds shared by e.g. Kim. The parents of said seeds presumably did *not* require stratifying, in view of Kim's M.O., and seeds that should have "germinated like grass seed" have given me nothing due, I assume, to my poor treatment. The seeds that yielded stellar results from my process will probably fry in our summers.

I am thinking that stratification in the 40's to 50's (say, near 10 degrees C.) would probably be best. Just wondering if it warrants the investment in a micro-fridge and regulator, or even "gifting" my wife a small wine cellar for Christmas in which to stash seeds. ;-)
Philip F.
[size=small][color=#669966]Zone 8 / Sunset Zn 30 (Austin, TX -- formerly New Orleans, LA)[/color][/size]

betsobon
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Re: stratifying in the south...

Post: # 68848Post betsobon
Fri Dec 28, 2018 10:26 am

I've been stratifying in the fridge for a few years. I'm a novice and have a hard time after the stratifying/germination. but I usually get a nice percentage of seeds to germinate in the fridge. I put them in a little seed starter, dampened in a small ziplock bag in the fridge. Our fridge is about 37%. We did have to get a new fridge earlier this year, so we will see how this batch comes out. I'm still collecting hips!

jrichardson
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Re: stratifying in the south...

Post: # 69008Post jrichardson
Thu Jan 17, 2019 6:59 pm

I have a wine fridge in my sunroom which I use for stratifying. I also stratify my daylily seeds and store other veggie and flower seeds. I only give up space for two bottles and it works great.

J Richardson

philip_la
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Re: stratifying in the south...

Post: # 69009Post philip_la
Thu Jan 17, 2019 10:10 pm

Joan, I think your space allotment/prioritizing seems about right for me. ;-) (2 bottles worth should hold an awful lot of seeds, and you *need* the space for other purposes!) But you confirm what I have suspected about temperature. We keep our fridge barely above freezing -- just enough to hopefully avoid frosting our salad greens. My impression has been that it might be a tad too cold for some species. I just bought an old used "dorm-fridge" which I have yet to plug in that I might use moving forward at its warmest setting... I'm guessing low to mid 50's is cool enough for most species? Do the zone 2 and 3 roses germinate okay at that temp, or should I plan on the real fridge for them?
Philip F.
[size=small][color=#669966]Zone 8 / Sunset Zn 30 (Austin, TX -- formerly New Orleans, LA)[/color][/size]

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