AusBonsai

I have sown some dissectum maple seeds approx 100 from my garden again this year and 6 have got to 200mm high. Last year did the same and got 3 and grow through to this spring just gone and came into leaf and then the died, knowing what happened is there any merit in feeding more potassium now to strengthen root system ? Reading old posts any information regarding this would by greatly appreciated!

My experience with weeping type maples shows they are very weak when grown on their own roots. Out of several hundred I've only has one that survived for more than 2 years. In actual fact that one lasted for around 10 years but finally dies last year.
I have seen a group of dissectum seedlings that's still going strong after about 10 years so it is possible - just does not work under my conditions.
Losses here are so predictable I started grafting likely specimens during the first summer to get them on more resilient standard seedling roots. When grafted they grow no problem.

I have not tried extra K so will be interested to see if it does yours any good.

Same experience here, what I find interesting and what may keep me trying a few different methods, is that they seem to grow really well the first year, equivalent to other maple seedlings and they even tolerate harsh full sun with minimal burnt leaves, they head into dormancy looking healthy and then there's huge loses coming into spring. Are the roots just disease prone during winter? They seem strong enough through summer.

My first batch I only have 2 left out of 50 or so.

I bought seed from shibui two and a half years ago now? (I think...might be 3.5) and a lot of the dissectum seedlings are still going ok. They're all in tiny pots as groups, (mixed) and mostly kept in the shade house. 70% shadecloth, which is very old, fraying and hail damaged...lol.

I'm not very reliable on fertilising....but they do get watered every day.

I'll get some pics.

Edit: scratch that, They all appear to have left the building. I'll have to keep a closer look on them in future.

These are just standard maples, yes?

No sign of weeping in those seedlings so I'd expect they are from one or more of the upright varieties of JM.

You appear to have a good variety of leaf shapes among those seedlings so even if they are not weepers they are still interesting.

Cheers Neal, I agree, pretty sure there are no weeping maples. My ignorance is showing, I thought dissectum was just a variety with fancy leaves, didn't realise it was a weeper as well.

Learn something new...

The seedlings in the picture are seeds from Acer palmatum dissectum ornatum bronze it is a weeper in my front yard planted 20+ years ago, have other weeper which never seed not sure why, I trying to collect many different varieties as I can they are a wonderful trees, any tips on other varieties which people can recommend?

Sorry James. I was referring to the pictures that Mel posted after yours.
You appear to have a couple of standard, upright types in the tray which should grow well but most look like they are from some sort of dissectum which are often unreliable as mentioned above.

You need to understand the variability of JM when grown from seed. Apparently the species exhibits more variation than some others which has allowed gardeners to select so many different types over hundreds of years. Now that we have planted so many different sorts in gardens the variability is even more pronounced both through unstable genetics and cross pollination from other nearby JM.
That all adds up to more variability when growing from seed so we expect any batch of JM seed to produce a range of different leaf shapes and colors. As the seedlings grow it is likely we notice other different traits - size and shape, hardiness, pest and disease resistance.

Every seedling is a new and unique combination of genes so each seedling is a new individual which is different in one or more ways from the parent plant. You can give any seedling a new cultivar name if you wish but should never use an existing name for any seedling.

If you want to grow a specific JM variety it MUST be propagated asexually - cuttings. layering or grafted.

Good bonsai can be grown from seed. Most great JM bonsai are seedlings and I find seedlings seem to give me better, stronger trees to develop as bonsai. I just cannot give them an existing name even if they LOOK similar to an existing cultivar when seed grown.

In general terms:
I steer clear of most red leaf JM types as the leaves tend to be larger and they usually have longer internodes which makes it difficult to develop compact trees.
Weeping varieties are also difficult to work with. They tend to be less hardy than upright types and are difficult to shape except as weeping shaped trees.
Seryu is a cultivar that does appear promising. It has relatively small leaves and compact growth and is the only upright variety that has deeply dissected leaves.

Also worth noting that JM are not easy as bonsai. They have a number of traits that make them more difficult to grow and develop unless you have good skills and knowledge of techniques and care. Trident maples give us most of the good aspects of maples as bonsai but are far more forgiving and much quicker to develop as bonsai.

I was going to mention Seiryu Shibui!

A brilliant dissectum cultivar that according to Denis Vojtila produces strong seedlings that grow true (?similar) to type 50% of the time. Although it is upright which probably accounts for its strength. Sadly I lost my young Seiryu last winter to the infamous black stem at ground level, I'm guessing it's crown rot from staying too wet during our warmish winters?

SquatJar wrote: ↑January 10th, 2022, 12:09 pm I was going to mention Seiryu Shibui!

A brilliant dissectum cultivar that according to Denis Vojtila produces strong seedlings that grow true (?similar) to type 50% of the time. Although it is upright which probably accounts for its strength. Sadly I lost my young Seiryu last winter to the infamous black stem at ground level, I'm guessing it's crown rot from staying too wet during our warmish winters?

Had the same black stem experience with a young Katsura upright, absolutely spewing

A brilliant dissectum cultivar that according to Denis Vojtila produces strong seedlings that grow true (?similar) to type 50% of the time. Although it is upright which probably accounts for its strength. Sadly I lost my young Seiryu last winter to the infamous black stem at ground level, I'm guessing it's crown rot from staying too wet during our warmish winters?

My experience with Seryu seed is nowhere near 50% true to type. I get around 1% that have deeply dissected leaves. Way more have far less dissected leaf shape. Of the few with dissected leaves only occasional seedlings look the same as the parent. Close examination shows plenty of differences in the amount of dissection and how deeply divided the leaves are. Even if the leaves look similar there can be other genetic differences as mentioned earlier - growth rates, mature size and shape, vigour and pest resistance are just a few things that genes can influence.
My experiences could be skewed by having many different JM cultivars nearby in the garden meaning plenty of opportunity for cross pollination. Seed from a lone Seryu would have less outside genes mixed in by cross pollination so the seedlings may be more uniform.
Even a similar looking seedling should not be called by the parent's name because of the regular and constant recombination of genes through sexual propagation.

One thing I have noticed about Seedlings from Seryu seed is they are generally strong and vigorous and usually seem to have shorter internodes than some JM seedlings.

I've also experienced the dreaded black stem disease. Seems to affect plants that are kept too wet or too protected through winter and a couple of mildly affected trees recovered when they were kept a little drier in a position with good air circulation.

I have a large Germains Gyration dissectum which i was planning to do a airlayer as this cultivar is quite unique. If it even takes would i be worth as they would be on their own roots and not as strong as if they were grafted.

What about the idea of root grafting a few Acer seedlings to base of the tree. Has this been done before to help the tree survive and be stronger as if it were to be grafted.

thanks,

I cannot recall anyone posting about root grafting weeping AP but in theory it should be possible and would overcome any problems with graft swelling and change of colour on the trunk.
Please start a thread when you do your grafts to document so others can learn from your trials.