Making Cold Stratification Easier

George,

I received your email.

thanks,

bill c

You’re welcome!

I was feeding the fish when I remembered activated charcoal. I also have some in pill form in the event that I eat something bad like gluten. The former are chunks and the latter is powder (in a capsule). I’d like to do an experiment trying normal stratification in seedling mix, and also stratification in sand only, activated charcoal only, and seedling mix w/ activated charcoal powder. The problem with the last part is that it’d probably absorb minerals instead, lol. Those little pills are potent though. One can neutralize an entire digestive system in about 30 minutes flat.

Activated charcoal is carbon, like graphite or hi-rank coal so it ought not to bind minerals much at all. the idea is that the flat surfaces of the aromatic 6-membered carbon rings have a strong affinity for similar molecules and many contaminating substances are built up of such aromatic ring systems. so they stick. The activated charcoal has a huge surface area per unit volume so it has lots of place for things to stick. That’s why it is used to take the color out of synthesized organic materials that are supposed to be colorless to our eye. The color means big complicated aromatic systems are present. They tend to stick tighter than the colorless stuff in most cases. Plant hormones like IAA, auxin, gibberellin, abscisic acid etc all are based on aromatic rings. So activated charcoal will, in principle, remove whatever leaches out of the seed/achene. That may be a good or bad thing, depending on how germination works.

Only one way to find out.

For the use of charcoal see link below.

Link: www.journalarchive.jst.go.jp/jnlpdf.php?cdjournal=jjshs1925&cdvol=61&noissue=2&startpage=383&lang=en&from=jnltoc

I’ve even eliminated the paper towel and just put wet seeds into the small zip-lock baggies all by themselves and toss them into the fridge. I tend to soak the seeds in a diluted bleach solution followed by several rounds of washing with water. So they start off wet. I gave the seeds an extra month in the fridge this year and so far things are really popping. I broadcast the seeds into trays that have organic pro-mix on the bottom and then cover them with builders sand. I’ve never had an issue with damping off, the fungus knats are minimal, after several months algae does sometimes start to appear on the surface of the sand. The trays go under grow lights in my basement where it is cooler and I tend to transplanted the seedlings into small pots once the first true leaf starts to develop.

It’s great to see that so many methods produce the same goal of increased germination. I know that I have been slow to change what I am doing when what I am doing seems to work, but I know that there will always be an easier, less time consuming way to get the job accomplished.

Thanks for all the input!

Jim Sproul

Here is a totally mad experiment I am doing.

Last year I did a crazy experiment and put some OP Iceberg achenes in a baby food jar filled with tap water, and chilled it in the fridge for exactly 8 weeks (I don’t even think I changed the water more than once in that period of time). I got in the order of 10% germinations a few weeks after sowing in a soil based media (at the time I had no clue that such a media could also contain critters that could kill of some of the sprouters).

It was so unexpected a result, that this season I have put a few hundred OP floribunda achenes in the same set up as you can see here:



This has been in the fridge a few weeks already…This time, I am changing the water every time it goes a bit tinged, say like once a week. I am curious to see how this seed germinates, it is not triploid this time, it is tetraploid (I am pretty sure of that)…so maybe there will be a higher than 10% germination rate. Anyone would have thought all the seed would rot, but there you go!!!

Hi George,

Looks like a fun experiment.

I did something similar with seeds in a big glass container with an aquarium “air stone” hooked to a pump via plastic tubing, thread through the refrigerator door! I didn’t keep numbers, but there were some germinations to my surprise also.

Jim Sproul

Yeah it has been a lot of fun to test the limits of these things!!

Germinations are coming along without variation as compared to previous years, so I guess it worked!

Jim Sproul

Link: sproulroses.blogspot.com/2011/03/germination-update.html

Hmm. I make my standard potting soil mixture (equal parts peat, soil, & sand… can add a little bone meal and lime). I fill pots with this, sow the seeds on top and cover with 3/8" of sand. This year I had major problems with birds and rodents. Next year I think I may try covering the pots with saran wrap. Also this year I tried an experiment and dried some seed and sowed in February instead of sowing all my fresh seed in Autumn. I think I had better results with early sowing- but it’s still too soon to tell for sure.

The achenes in the bottle I pictured above have completed their 8 week proposed water soaking in refrigeration.

All looked pristine and there was almost zero mold on them.

I randlomly selected and opened two achenes up to check for any evidence of seed rot, and this time both seeds contained macerated embryos.

This proves the obvious, that this method risks losses to seed death.

I expect some will germinate despite the extreme wet. Definitely not a method for serious players, but for me it was ok to do as a fun trial!

Just reporting that the seedlings that germinated have now begun to bloom. There was no apparent harm in making stratification easier.

Jim Sproul

Link: sproulroses.blogspot.com/2011/04/2011-seedling-update-seedlings-about-to.html

I’m doing something different again this year too (borne out of being time poora atm)… When I shell the seeds from the hips I usually put them into an envelope with the cross written on it to store until I’ve got all of them harvested. So this year I just left them in the envelope, dunked the envelopes into a container of water and then stacked them together and put them all into a large ziplock bag and straight into the fridge… did 100 envelopes of seed this morning in 5 minutes :slight_smile: Still got that many again still on the bushes but if this works ok it will cut my handling time down a huge amount.

Funny that!

I decided to experiment with this topic lately, as well.

I read somewhere a few months back I think it was, (maybe here) about putting the achenes in a sandwich baggie and then spraying some small amount of water inside it, and then seal it off as usual and pop into the fridge to cold stratify (ie. the idea being to try and do away with the paper thing altogether).

I have tried this recently on some OP seed…now I am curious to see if this trick works out ok!

I’ve cleaned the seed, dried them if I had to wash them, otherwise just put the shelled seed into the snack size baggies with a label, then refridgerated them to hold them until the weather cools enough to plant. It’s worked quite well most years. I hated the slimy, moldy toweling and felt the mold that developed seemed to inhibit germination many times. There isn’t any mold in the baggies not using toweling or water. Check out the Snack Size bags. They’re large enough to put a few cookies in, about a third the size of the sandwich size and are perfect for smaller batches of seeds. It bugged me having to use sandwich size for a few seeds. This is more space saving and far more cost effective. Kim

My seed in the sealed baggy sprayed with some water (and no paper toweling) is nearing the 8 week cold strat mark. There is NO moulding thus far, and the seed looks pretty ok (OP Foliolosa). Will sow it in a couple weeks time.

:0)

Just following up on the paper-less baggy trial mentioned here.

I know others on this forum have mentioned this method as well.

This OP foliolosa seed (mentioned in my posting above) ended up cold stratifying for 6 weeks before sowing. I sprayed droplets of water in the plastic baggy, made sure there were no puddles of water at all by draining excess water, and omitted using paper toweling.

Since sowing the achenes a few weeks back now, germinations have been occurring without any apparent problem.

I did not do a parallel control with paper toweling, but this result is good 'nuf for me!

I’ve come to prefer well-composted organic material, such as commercial compost; I find that by using media that may be sterile (paper towels or peat), pathogenic organisms sometimes tend to get the upper hand in batches of seed. Logically, it seems to me that starting with a medium that has a healthy mix of competing microorganisms or no medium at all may be preferable to loading up your stratification container with sterile food for whichever bacterium or fungus happens to get there first or grow the fastest!

Personally, I also find that drying seed after removal from the hip and prior to stratification helps to reduce losses to mold, especially with small seeds or seed with very thin achene walls (such as what tends to come from Synstylae species or their closely related hybrids). Aside from physically hardening the exterior achene wall, I’m not sure of the mechanism involved, but the effect has been significant for me.