Norm Deno's "Outdoor Treatment" - anyone try it?

I was looking through Deno's book on germination and noticed his comments about what he calls "Outdoor Treatment." You put the seeds in paper towels and then baggies as usual, but instead of cold stratifying them in the fridge, you put them in an outbuilding, like a shed or garage, and let the temperature fluctuations break the seed's dormancy. I decided to try this with a bunch of seeds that need cold stratification, but I was wondering if anyone had tried this yet and what the results were. It is not clear to me from looking at his book whether this does NOT work with any plant that requires cold stratification.

i havent tried this but sounds like a good idea, i usually plant mine in pots and in baggies and then out side for their treatment and then they come up in the spring when it gets warmer unless we get warmer before spring but then you have to bring them in when they sprout, so that might work better not sure just have to try it and see is the best way for me

It sounds like wintersowing to me..

Well, winter sowing involves planting things in soil, covering it with something that you then gradually open, and making use of snow. This "outdoor treatment" he describes doesn't involve soil, opening the covering, or snow: you put stuff in a paper towel in a baggie and put it in a shed. It's basically the paper towel method he popularized, except you put it outside instead of in the fridge. It's the temp fluctuation that it makes use of; light is specifically excluded, just like in the fridge. According to him, some seeds will *only* germinate using temperature fluctuations. But as of his 1993 book, he had just started doing it and hadn't tried it on that many specie compared to the 4000+ species he had tried germinating in paper towels at straight 70F, 40F, or a long fluctuation, like 40F - 70F - 40F for a month or so each. So I am wondering if many people have tried it. I've had his book for several years and just noticed it myself. I would like to know what differences there are between it and fridge stratification. He does say some seeds are killed by this treatment.

Deno described planting in a pot and putting it in a plastic bag outside on the north side of the house and then opening the bag once it germinates. This was in 1993. This is pretty much what was much later described as winter sowing, except it doesn't make use of snow.

Hello Paracelsus - Did you try germinating anything last winter using only a paper towel in a baggie exposed to fluctuating outdoor temps? I'd love to know what happened - both whether something did or did not germinate - and to what plant the seeds belonged.

Thanks for any input in advance,
Karen

Yes, in fact I tried germinating 75 different seeds with Norm Deno's Outdoor Treatment. All but three seed groups germinated with this treatment. I consider this to be phenomenal success for any kind of cold stratification method. He advises using cheap sandwich bags that don't zip but just fold closed because it allows in more oxygen. I used these, but for wetting the paper towel, I used a weak solution of liquid kelp, as I always do.

Some things I realy liked about Outdoor Treatment besides the high germination rates:
--I could keep all 75 groups of seeds in a small box.
--I could check them easily for germination in the comfort of my [unheated] garage just by holding the baggie up to the light coming from the window.
--I could pick off the germinated seeds (or tear of bits of the paper towel--this works just as well) and leave the duds behind.
--I had more room in my refrigerator for just storing seeds, lol!

I highly recommend this method. It beats the daylights out of cold stratifying in the fridge or fiddling with plastic takeout containers.

The more severe sort of Outdoor Treatment he describes for plants that love deep cold, like aconites--planting in a pot and setting it in a baggie on the north side of the house--works very well also.

This message was edited Dec 15, 2007 7:22 PM

This message was edited Dec 15, 2007 7:23 PM

Good find, Karen!

Paracelsus, did you try it on seeds that didn't require cold stratification, too?

Paracelsus, thank you so much for getting back to us with your results. Ditto to Pagancat, I'd also be curious to hear if you tried this on seeds not expected to require cold stratification. But one thing that occurs to me here is that anything we do along these lines for now is going to be an experiment. So, we might as well get busy and try this on a small portion of any seeds we may have on hand to see what happens.

Well, we all are delighted to expand our winter sowing techniques with this. Thank you Paracelsus.

My hill is too treacherous in winter to get to any outbuilding, so I think I'll just acquire one of those small fiberglass (plastic?) storage boxes to put outside the back door to house my baggies.

And then, maybe I'll also acquire a 5' or 6' long storage box, poke some drainage holes in the bottom, put maybe 12 layers of newspapers over that and fill up to at least 6" with sand and wet it all down. As the seeds germinate in the smaller box, I'll put them in 4" pots with sandy potting soil, and then house them inside this larger box on the sand (for drainage and keeping away slugs). I'll keep the lid around for torrential rain, but otherwise keep some wire fence on top to protect against critters so that snow, sleet or gentle rain can get in.

I know it's recommended to use larger containers like milk jugs - and I will never germinate primroses any other way - that worked wonderfully. But last winter I did find that the closer to the spring equinox I sowed, the smaller the container I could use. Small styrofoam coffee cups in mesh-bottom flats were easy to lift and water from the bottom - much more so than the larger containers - and germination was very good.

I'm thinking out loud here - how does what I've written sound, so far? Is there any thing I could do differently or better considering my deficiencies in getting around on my hill like a mountain goat in winter?

Karen

Gosh, I wish I could tell you what I've tried and haven't, but honestly, I've never attempted winter sowing before (I don't think it would've worked in Phoenix, really!). I wasn't even aware that the size of the container mattered.

I got a lot to learn.

Paracelsus, I've heard of Norman C. Denos book. did he mention using Gibberellic Acid, instead of doing the stratification? I have the Ken Druse book Making More Plants. and it covers a lot of different techniques for hard to germinate seeds. and lists each Genus and how to propagate it. does the Deno book list them individually? Jim

Just a comment from an ol' southern gardener who propagates a great deal - if you live up north, especially like New York, cold stratification works great outside, because that's what happens in colder climates. Where I live, we don't get the chilling hours outside, so we use an old fridge. Most of my mentors have all said that moisture is important in maximizing the effectiveness of cold stratification, so just putting them in a container in a cold environment probably doesn't work as well. I do all kinds of oak acorns, dogwood and redbud seeds. Breaking down the outer coatings of some seeds takes a bit of extra effort. You folk have some really interesting discussions on this forum. My hobby is propagating woody plants and formosan lilies. Good gardening to you.

pagancat, no, I didn't try it on seeds that don't require cold stratification. I have always had good luck with germinating annuals and perennials that don't need cold at what is for me room temp--65F--using the baggie method. Exceptions, of course, for warm germinators like datura, peppers, and such. IME, these are usually tender perennials anyhow and for them I use the baggie method on a heating pad.

Once the temps begin to warm up in spring (so that there were regular times when the temps were well above freezing), the seeds started germinating. Then for the most part I took the germinated ones out of the baggies and put them in peat pellets or cell paks and set them in shade outside, usually next to a wall so there was a bit of warmth, or in one of my portable microgreenhouses under a pine tree. Whenever it got to freezing, I would either bring them in (these little greenhouses are just shelves with heavy plastic covers and wheels) or just zip up the greenhouse cover or cover them with a blanket (microfleece works well). I often start seedlings inside and have a lot of shoplights set up for that purpose, which work great for seedlings, but with 75 sets of seeds, I had most of them outside. One thing I learned from this was not to start so many of the same seed, lol!

hostajim1, he does talk about gibberellic extensively. This was why I originally bought the book. I have some and I tried using it, but I have never been the neatest person in the world and find it a bit too fiddly for my taste, especially since I have had such good results with his Outdoor Treatment. He does indeed describe the germination methods for I think 4000 different species. He has tried 40F, 70F, and a warm-cold-warm, cold strat, just all kinds of methods for various seeds. If you grow a lot of perennials, it is definitely worth having his two books.

bluespiral, I moved and this year I have not got a garage or shed, so I am going to try using an old metal cabinet on my covered patio and the wooden steps to the basement. I have actually got a bunch of aconites on the basement steps right now. Those, though, I put directly into small pots and then into plastic bags. This is what Deno describes as a good treatment for aconites. I did try this two years ago and good some good germination on some aconites, zip on others. I just need to move them to the north side of the house now that we have entered full winter.

I hope folks will try his Outdoor Treatment. It has taken a lot of the mystery and hit-or-missness out of germinating seeds that like cold.

Thanks so much for all that info, Paracelsus, I really appreciate it!

Paracelsus, thanks again from me too.

Paracelsus, good info, I will have to buy N Deno. book thanks, Jim

I found Norman Denos web page. it lists whats in the book, Jim www.theseedsite.co.uk/normdeno.html

this sounds a lot easier than winter sowing.

Wish the book was available on Amazon, lol... might just have to send the $20 check and hope he's still sending it out!

This is fantastic information - thank you so much, everyone. I have avoided doing any wintersowing because I am put off by all of the plastic containers that that method requires. This sounds like a wonderful alternative.

Cheers!

Okay, as someone who has never winter sown nor tried this outdoor treatment before, I have a question. I really like this "Deno" method and want to take the plunge, but I am wondering if you can recommend starting *very small* seeds this way? I have several poppy varieties that I want to start, and also have some petunia seeds (TINY) and am wondering if I should stick small seeds such as those into clamshell style containers (w/ good soil-less mix) as opposed to paper towels.

I have started very small seeds using the baggie method. When I see evidence of germination, I gently tear off bits of the paper towel and press it into my preferred starter, which is Jiffy 7s. Given good contact with moist soil, the seeds easily grow right through the paper. I have done this with artemisia seeds, which are almost like dust.

Whoops, I guess that you had already said that earlier, Paracelsus - sorry! That's a great idea - I'll give 'er a whirl.

Has anyone ever had a problem with leaving the seedlings in the bag too long? I'm wondering how large you should let them get and would hate to over-do it.

I plant them as soon as they start to germinate. That said, I have sometimes forgotten about things. I've done this more with stuff that needs warmth, though. There have been times I used the baggie method for datura seeds, leaving them on a heating pad for warmth. I kept checking them and nothing. Forgot about them and came back to find them looking like mung bean sprouts with the leaves all yellow and also squashed from the cats deciding to help germinate the seeds by hatching them.:)

>big smile<

I, too, am owned by such creatures....

Whew! I'm a wintersower and my thought in reading this was "It sure is easier to wintersow". This involves basically moisten potting mix, fill a milk jug, sprinkle seeds on surface, tape closed, stick out in the snow and forget about it.

Move on to next container...

writie: I was unclear: Were you questioning whether you could use the Deno method, or wintersowing, for very tiny seed? Well, seed size or type doesn't matter at all in wintersowing, I don't really know anything about the Deno method.

Karen

Actually, I'd prefer the Deno method because it doesn't require all of the containers, but I was asking because I thought that perhaps the *tiny* seeds were better suited for WinterSowing -- does that make sense?

Wintersowing works for any size of seeds. It works beautifully for tiny seeds (like poppies and digitalis) but I also do it for very large seeds like nasturtium and moon vine

Karen

Poppies March 3

Mixed poppies in summer

breadssed poppy

I've got poppies sprouting under lights in my cellar right now -- I LOVE THEM! Gorgeous poppy bed, kqcrna!

Thank you. They really are great for wintersowing. I liked the regular Flanders poppies with blue bachelor buttons, they bloom at the same time.

Now I'll butt out let let you continue with your Deno method. Sorry for jumping in uninvited.

Karen

Was this thread about winter sowing? No, it was not. So why did you feel obliged to insert five posts about it? Is it threatening for someone to post about a method of germinating seeds that is actually much more efficient than winter sowing? Sheesh.

This message was edited Jan 4, 2008 9:51 AM

Well, you can bet I won't again. I knew there was a reason why I don't visit this forum. I'll go back to a friendly one. Thank you for the hospitality.

It's true. We are known for being mean in this forum. Especially me. Everyone who knows me says I am really really mean.

Btw, you can just throw poppy seeds on the snow and they will germinate in the spring. I read about this in Ken Druse's book, Making More Plants, and I tried it myself and it works.

Boy, I wish that we actually got some snow around here because I've been wanting to try the poppies-on-snow method for some time now.

Anyway, I did set some seeds out in my shed a week or so ago using the paper towel method. I assume that I should check these once/week just to be safe, no? I figure that in my zone (approx. 7a), it's possible for them to germinate before Spring arrives ...

I love that snow-planting thing! We've had snow, but now it's melting as we head for a patch of weird spring-like weather--supposed to be in the fifties for the next several days. This after having 2F the other day. I threw a bunch of old seeds out the other day around the edges of the yard, hoping some of them might have enough life left in them to germinate in spring. Meanwhile, I'll be starting a bunch of cold stratifiers using the Outdoor Treatment method in the next week--14 different kinds this year, mostly a bunch of native shrubs for hedging and some alpine strawberry seeds.

Er, that didn't take long. I checked my seeds today and most of them (dianthus) have already sprouted. lol Guess I need to throw them in flats and stick them under lights in my cellar now? What would *you* do?

That, exactly.

They were all dianthus? Of only one type? How long were they in there - 2 or 3 weeks?