Andre, I see this question has gone unanswered both here and at GW. I'll try to take a stab at it. In seed-bearing plants, seed-set is related to maturity. Maturity in plants isn't a linear age-related quality. It is possible to return a mature plant to juvenile-type growth through heavy pruning, and it is possible for a plant to have both mature growth and juvenile growth on it at the same time. In general, "mature" growth in Japanese maples is twiggy with reduced leaf size and increased variegation, while juvenile growth is more vigorous and tends toward larger leaves and less coloration characteristic of the cultivar. It is possible to manipulate onset of maturity through stress. Plants that think they're facing certain death will often set seed as a last resort to save the bloodline, so to speak. In commercially produced Japanese maple cultivars, timing of seed set can be influenced by the use of scions from mature-type growth. In fact, if the seed tissue has already formed in the bud, a brand new graft will push that bud and display the seed the next spring. My guess is that in a normal growing situation, you should see seed set capability within the 5 to 10 year range, but sometimes earlier, and some cultivars simply don't set seed at all. As for prolificacy, the trees in my little world that are regularly covered with seed include Viridis, Moonfire, and Higasayama. I've collected seed from at least 25 other cultivars, but not with the wild abandon that those three consistently allow. Hope that gives you something to start from! Susan
Thank you Susan. Is it just a guess or did you already try to sow a seed and see its seeds 5 years later ? Does that also mean that any standard palmatum grown since 5 years in good conditions without being pruned should bear seeds ?
I really wasn't thinking about seedling-grown maples at all. I was mentally re-visiting all of the trees I've collected seed from, and thinking back to how old they would have been when I first had the opportunity to collect. These trees are all grafted cultivars. I was also thinking about a couple of 3-year-old grafts in my greenhouse that have a small seed set this year, which I think is very unusual. The seedling-grown trees that I have collected from are all over 30 years old, and were bearing seed long before I made their acquaintance a decade ago. I do believe that seedling-grown trees will take several years longer than some grafted cultivars to come to sexual maturity. Please also note that I'm not talking about heavy, reliable seed set either. Many of the trees I'm thinking of only produce a handful of seeds, and not every year.
Susan/SilverVista- Found your posts informative. I just started a new post 10/2/2005 "collecting samaras". I've read many websites on maple seeds&germination and this Fall is my 2nd year of germinating. I have many cultivars and last year I planted seeds right off my trees in mid-late October without refrigerator stratification. Early October has come in very windy and I am picking some seeds bit earlier so I don't lose them to the wind. I have found brown seeds (with brown wings) and green seeds with brown wings on my same Katsura. I assume it is OK to plant the green seeds (with brown wings) and that the embryos are mature and fully formed. On the same shirasawanum I have green seeds with brown wings and green seeds with green wings- are both seeds OK to plant now (10/03/05) ? I have a 10 year Shaina that never has a seed and the same with 1 of my Shishigasari's. I have an 8-10 year red Red Filigree Lace that finally has produced 1 paired samara this year (seed and wing are still all red so I assume it is too early to plant even though it is 10/03/05? I find my dissectums in general produce few if any seeds. Why is that? Also, I have 2 large Fireglows that produced many seeds Fall 2004 and have none this Fall2005. How come? Any idea? Sorry for such a long post, but I am fascinated with these seeds, and you seem to have some answers. Thank you.
Hagoromo. Mine is 7 years old and have never seen a samara. This has been confirmed by Cor Van Gelderen who told me that he has never seen seeds at his Hagoromo plants. Anybody with a different experience? Gomero
Hi, My Hagaroma bears seeds every year. It is a mature plant with a 1 inch trunk diameter. regards Wolfgang
Hi webwolf, Your answer, and photo!, proves that we should be careful about making generic statements. I will not suggest that Hagoromos are happier in the southern hemisphere ;o)); Gomero
Did you try to sow these seeds and if yes, did you get something close to hagoromo or back to palmatum palmatum ?