Blue atlas cedar - how to collect seeds and plant them?

[Aphystic]

I’m not sure if I’m bad at the search function on this website but I have been struggling to find detailed information about collecting and growing a bonsai from a blue atlas cedar cone/seeds.

(I can’t find any retailer that will ship a live blue atlas cedar nor seeds to Sweden. Hence why I’ll try another route)

Maybe someone who has done it can chime in?

How do I collect seeds, how should they look, how should they be stored and how and when should they be planted? (What kind of soil, pot size, indoor with grow light, outdoor? At what temperature, when etc?)

My parents will be travelling from Sweden to Poland, Czechia, Italy and then back by car. Maybe there’s someway along the way or just place with plenty of blue atlas cedar?

 

[Shibui]

Cedar cones mature then begin to fall apart while they are still on the tree. Individual cone scales and seeds drop to the ground. I collect cones as they begin to fall apart on the tree. I assume that all cones on the tree are at around the same stage so when some are disintegrating others that are still tight should also have ripe seeds.
My strike rate with cedar seed is quite poor with 3 04 4 seedlings from 50 or more seeds but we did have a post recently where another grower reported much better germination. I think the key was sow fresh seed before it dries out.
Will try to find that thread.
Found it : https://www.bonsainut.com/threads/blue-atlas-cedar-seeds.58162/#post-1006084 Post #5 by @Moraito

 

[Aphystic]

Cedar cones mature then begin to fall apart while they are still on the tree. Individual cone scales and seeds drop to the ground. I collect cones as they begin to fall apart on the tree. I assume that all cones on the tree are at around the same stage so when some are disintegrating others that are still tight should also have ripe seeds.
My strike rate with cedar seed is quite poor with 3 04 4 seedlings from 50 or more seeds but we did have a post recently where another grower reported much better germination. I think the key was sow fresh seed before it dries out.
Will try to find that thread.
Found it : https://www.bonsainut.com/threads/blue-atlas-cedar-seeds.58162/#post-1006084 Post #5 by @Moraito

Nice read, helped a bunch.

When should I be sowing (grow light or natural?) indoors or outdoors? Also what kind of soil?

 

[Shibui]

No good asking me for tips. My success rate is very poor.
You can try searching for online advice for germinating cedrus but don't be surprised if some of it is contradictory.
When in doubt I try to emulate conditions that the seeds would get naturally -
for autumn ripening seed in cold climates sow in fall and lave it to experience cold winter.
for warm climate species sow when the fruits are ripe but no cold period.
for spring or summer ripening seeds sow straight away outdoors.

I am not experienced in growing in cold climates like Sweden but I'm not a fan of sowing seed indoors. Too many problems when seedlings do not have natural light or moving air. There seems to be very little difference in growth after a year anyway.
I know some growers manage indoor seed germination but mostly those with extensive experience who can anticipate problems and provide better conditions to mitigate those problems.

 

[Aphystic]

No good asking me for tips. My success rate is very poor.
You can try searching for online advice for germinating cedrus but don't be surprised if some of it is contradictory.
When in doubt I try to emulate conditions that the seeds would get naturally -
for autumn ripening seed in cold climates sow in fall and lave it to experience cold winter.
for warm climate species sow when the fruits are ripe but no cold period.
for spring or summer ripening seeds sow straight away outdoors.

I am not experienced in growing in cold climates like Sweden but I'm not a fan of sowing seed indoors. Too many problems when seedlings do not have natural light or moving air. There seems to be very little difference in growth after a year anyway.
I know some growers manage indoor seed germination but mostly those with extensive experience who can anticipate problems and provide better conditions to mitigate those problems.

I suppose you just try with 1 seed in each pot? So I could have a few indoors and a few outdoors and see which one succeed?

 

[Shibui]

I suppose you just try with 1 seed in each pot? So I could have a few indoors and a few outdoors and see which one succeed?

One seed to a pot is one possible way.
I usually sow hundreds of seeds so it is impractical to do 1 seed to a pot and any that do not germinate means the pot and soil is wasted. Seed is usually sown in community trays and germinating seedlings are then pricked out and planted into individual pots when they are strong enough to handle. The initial transplant is an opportunity to trim the roots to promote better lateral roots for better nebari later in life as a bonsai.
Here's a tray of Japanese Black pine seedlings. That's about the stage I would normally prick out into separate pots.




Here's another tray of JBP seedlings. They have been left in the seed tray longer than normal but give you an idea of community germination tray.


Smaller trays for smaller batches - again, JBP. Be advised that smaller trays are more difficult to manage as they can dry out too quick and kill the whole crop in just one afternoon of hot weather.


Community pots also used for other species.
Japanese Maple seedlings. Again, this was just a germination trial. I would usually have pricked these out into individual pots when much smaller but JM can be transplanted at any age so still useful even at this size.

 

[Aphystic]

One seed to a pot is one possible way.
I usually sow hundreds of seeds so it is impractical to do 1 seed to a pot and any that do not germinate means the pot and soil is wasted. Seed is usually sown in community trays and germinating seedlings are then pricked out and planted into individual pots when they are strong enough to handle. The initial transplant is an opportunity to trim the roots to promote better lateral roots for better nebari later in life as a bonsai.
Here's a tray of Japanese Black pine seedlings. That's about the stage I would normally prick out into separate pots.
View attachment 503941



Here's another tray of JBP seedlings. They have been left in the seed tray longer than normal but give you an idea of community germination tray.
View attachment 503943

Smaller trays for smaller batches - again, JBP. Be advised that smaller trays are more difficult to manage as they can dry out too quick and kill the whole crop in just one afternoon of hot weather.
View attachment 503944

Community pots also used for other species.
Japanese Maple seedlings. Again, this was just a germination trial. I would usually have pricked these out into individual pots when much smaller but JM can be transplanted at any age so still useful even at this size.
View attachment 503942

I see, looks easier and more neat than having 40 pots.

What soil would you use for this and did you keep them outdoors and from what temperature?

 

[Shibui]

I sow easy to germinate seed in the same soil I use for all the plants. Just a good quality potting mix will do. For more difficult seeds I use a commercial seed raising mix because it is relatively sterile which helps for some species. For seeds with special needs we sometimes need a tailor made seed mix.
For temperate species I sow the seed in autumn when it would naturally fall from the trees. The trays are left outside on the benches in the nursery all winter. The cold and warm cycles imitate a natural winter which helps some species which need cold stratification. They germinate when the weather warms up in spring as would natural seed in the forest.
Just need to make sure seed is protected from birds and rodents outdoors as seed eaters are very good at finding seed and eating it.

 

[Aphystic]

I sow easy to germinate seed in the same soil I use for all the plants. Just a good quality potting mix will do. For more difficult seeds I use a commercial seed raising mix because it is relatively sterile which helps for some species. For seeds with special needs we sometimes need a tailor made seed mix.
For temperate species I sow the seed in autumn when it would naturally fall from the trees. The trays are left outside on the benches in the nursery all winter. The cold and warm cycles imitate a natural winter which helps some species which need cold stratification. They germinate when the weather warms up in spring as would natural seed in the forest.
Just need to make sure seed is protected from birds and rodents outdoors as seed eaters are very good at finding seed and eating it.

Ok, but would you reckon it’s a problem to have it in a small pot outdoors when it’s below freezing everyday for 1-3months and days/weeks with -15c temperatures? Better to germinate in a cold garage or shed?

Thank you all so much for the help

 

[Aphystic]

If someone on here knows how to get ahold of seeds to a blue atlas cedar here in Europe I’d much appreciate the help, in case I don’t find any in the wild.

 

[Moraito]

As Shibui pointed to my post I will give some more insight on how I have done it. I repeat that I am not an expert AT ALL, not even an advanced amateur, so your results may vary and I may have been lucky. I have done this same thing 2 different times with good germinations.

Found it : https://www.bonsainut.com/threads/blue-atlas-cedar-seeds.58162/#post-1006084 Post #5 by @Moraito

In that post an explanation on how i did proceed. I sow outside after last frost date. (I take last frost date, deduct 2 months and the resulting date I open the cone and cold stratify in the fridge for 2 months) here you can sow all seeds in a big tray as Shibui does, it is the most efficient way and when seedlings are young atlas cedar also seem to handle this early transplant well (as with JBP I have even done the seedling cutting technique with Ok-ish result, but I do not think it is needed). But you can also move the stratifying whole thing to warm conditions and check every three days for radicle emergence and then sow only the seeds with radicle in individual pots, ensuring at least some germination in that one...

For soil I used something like 40 perlite/60 potting mix.

 

[Aphystic]

As Shibui pointed to my post I will give some more insight on how I have done it. I repeat that I am not an expert AT ALL, not even an advanced amateur, so your results may vary and I may have been lucky. I have done this same thing 2 different times with good germinations.

In that post an explanation on how i did proceed. I sow outside after last frost date. (I take last frost date, deduct 2 months and the resulting date I open the cone and cold stratify in the fridge for 2 months) here you can sow all seeds in a big tray as Shibui does, it is the most efficient way and when seedlings are young atlas cedar also seem to handle this early transplant well (as with JBP I have even done the seedling cutting technique with Ok-ish result, but I do not think it is needed). But you can also move the stratifying whole thing to warm conditions and check every three days for radicle emergence and then sow only the seeds with radicle in individual pots, ensuring at least some germination in that one...

For soil I used something like 40 perlite/60 potting mix.

Ok, so just an airy soil mix, that’s good! I have both perlite and normal potting soil.

So I would keep the cone as he said in a drawer until 2 months before last frost date and then put them on a plate in the refrigerator for two months, take ‘em out and plant them in the soil mix and just let them be outside?

Can they be put in my drawer in room temperature for 6-7 months?

1st of may there’s a 50% risk of frost where I live and 10% risk in the middle of may (18th~)

 

[Moraito]

o I would keep the cone as he said in a drawer until 2 months before last frost date and then put them on a plate in the refrigerator for two months, take ‘em out and plant them in the soil mix and just let them be outside?

Yeah, thats what I did. Just be aware that the stratification is not just putting them in a plate. You need to keep the seeds moist but not soaked. This can be done keeping them in moist sand or in some wet kitchen paper for example.

Can they be put in my drawer in room temperature for 6-7 months?

As long as they are still inside the cone they seemed to keep viability high for me.