Growing pines from seed?

nelstomlinson · Jun 9, 2016

I am trying to grow Siberian Pines from seed, with little luck so far. I planted 50 pre-soaked seeds in a flat, had two sprout after about 4 weeks, and both were killed by a white fungus or mildew.

The nursery I bought the seeds from said that they soak the seeds for 24 hours, then keep them in a plastic bag in the refrigerator for 90 days, then plant them. I tried that, and found that the seed shells were getting white fuzz growing on them after about two weeks in the fridge. So, I planted them and got the two sprouts that were killed by white fuzz.

Does anyone have any experience with growing pines from seed? Any ideas to keep the white mildew growth from ruining things? Is it really necessary to soak the seeds _before_ stratifying? I'm thinking about throwing some seeds in the freezer for a month, then soaking and planting. Does that sound like a good approach?

mranum · Jul 4, 2016

I dont come around here all that much but read your post and thought I would give my experiences. I have no experience with Siberian Pines, but as a grower of Christmas trees we grow White and Scotch from seed ever year. We stratify the seed in moist sterilized soil for 90 days minimum at 40 degrees. The plastic bag we use for this has to remain open so it can vent or it can damage the seed. After 90 days it gets planted and can still take several more weeks before it germinates. As soon as they germinate you must be on the watch for a fungus called "Damp Off". It is a fungus that you cant see that grows on the surface of the ground and will chew off the tender green shute in a matter of a few hours. A fungicide will need to be applied regularly until the stems begin to harden off and turn to a redish brown color. It can be frustrating and rewarding at the same time. Hope this helps some. http://www.extension.umn.edu/garden/yard-garden/diseases/damping-off/

nelstomlinson · Jul 5, 2016

That is very helpful indeed. It sounds as if I will need to keep a tray of soil and seeds in the refrigerator for three months.

My white mildew problem may have been caused by keeping the seeds in a sealed plastic bag in the fridge.

I have since gotten three out of ~100 seeds to sprout without any stratification, and so far those three seem to be flourishing.

I hadn't known anything about Damp Off. I'll have some fungicide on tap before I try starting more. I got a generous pound of seeds, about 2100 of them, so I have some to experiment with.

Thanks!

mranum · Jul 5, 2016

nelstomlinson said:
That is very helpful indeed. It sounds as if I will need to keep a tray of soil and seeds in the refrigerator for three months.

My white mildew problem may have been caused by keeping the seeds in a sealed plastic bag in the fridge.

I have since gotten three out of ~100 seeds to sprout without any stratification, and so far those three seem to be flourishing.

I hadn't known anything about Damp Off. I'll have some fungicide on tap before I try starting more. I got a generous pound of seeds, about 2100 of them, so I have some to experiment with.

Thanks!

No problem, there are some home recipes out there for damp off if you look.

PJM · Jul 29, 2016

The instructions provided by the nursery for Siberian pine are mostly spot on, but other sources suggest the pre-soak should be for 40 hours. Then place in clear poly bags (not sealed for 90 days at 0-1 degree C. After the first four weeks you may want to surface dry the seeds to prevent molds from developing. Sounds like you may want to surface dry them earlier if you were seeing early mold development.

nelstomlinson · Jul 30, 2016

PJM said:
The instructions provided by the nursery for Siberian pine are mostly spot on, but other sources suggest the pre-soak should be for 40 hours. Then place in clear poly bags (not sealed for 90 days at 0-1 degree C. After the first four weeks you may want to surface dry the seeds to prevent molds from developing. Sounds like you may want to surface dry them earlier if you were seeing early mold development.

Thanks. Keep them at 0-1 degrees C? Would just freezing work? Keeping them that close to freezing in my fridge means they will freeze.