RE: HYB: seed preparation

Robin, I used to have <very> poor germination. Less than 3%.

Several things were contributing factors - pots were drying out too much once temperatures started staying fairly warm in spring, temperatures were too hot by the time the late bloomers were starting to germinate, seeds were washing to the surface where they were drying out, temperatures were dropping abruptly into the low 20s just as seeds were starting to germinate, plus all the marginally functional parent plants in my growing conditions that I was working with were not producing the most viable seeds, and <maybe> some of the genetic combinations were a bit out of whack.

I started burrito'ing mostly to speed up the cycle from seed to bloom, but also to reduce some of those variables and now get much better germination than 10 years ago.

I still plant some seeds outdoors (mostly "junk"/"experiment" crosses like the cross that produced that cute surprise rebloomer this fall), but now use some of the suggestions Betty has posted.

She has described Paul Black's seed planting method here a couple of times, and while I don't bury pots in trenches, I do mulch pots while they are outdoors with a thick layer (4 or 5 inches) of shredded tree leaves. And bring all but the 'junk' crosses indoors if we get sudden temperature drops in late spring after it's been well above freezing for awhile (main reason I mostly use 4 inch square pots - lugging a bunch of big pots in and out of the house was awful!) Lots of 4 inch pots is bad enough!

From what I learned from folks here, optimal germination temperature for TBs is probably around 50 to 60oF (soil temperature), and mostly stops above 70oF. At warm temperatures, if the seeds aren't damaged, internal enzyme stuff can send the seeds back into deep dormancy requiring another winter chill cycle (or more) to get them to germinate.

For whatever reason, some crosses here have higher germination after a second long chilling cycle, no matter what I do to them. I've been able to get higher germination from some crosses by burrito'ing for 3 months, then put them outdoors or in the sunroom for a month of temperatures around 60oF, then transplant the babies, put the pot back into the cold for a couple of months.

Even that isn't enough for some of the stubborn 'cold climate' seedlings and more will germinate after a second winter outdoors.

Best germination here may be from seeds planted outdoors for 3 or 4 months (November until early March), then brought in to the cool sun porch to germinate. By that time, it is warm enough outdoors for seeds to start germinating, but temperatures are still really variable.

So maybe putting your pots under a cold frame in early spring would help. ?

On the other hand, I may be starting to get seedlings that are more sensitive to abrupt temperature changes than I want. Too soon to tell for sure.

Long winded - maybe something that helps, I hope.


--
Linda Mann east Tennessee USA zone 7/8
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