I've decided to try to grow different Japanese maples from fresh seeds this year (stratified them last year). Well the gist of the story is about 100 sprouted but about 70% - 80% of them wilted and died off. Is this a normal rate? What should I do to have a higher success rate? Every morning I wake up to 2 - 3 dying... what should I do?
An alarmingly high death rate. Pithyum disease from overwatering and / or overcrowding? To reduce risks, put each seedling in a separate pot, use a coarse, well-drained soil mix, keep in a well-ventilated area, and allow them to get nearly dry between waterings.
Use of a very free draining medium helps for palmatum seedlings. A covering of grit might help to prevent damping off too. Haven't had any problems with multi-plants per pot when grown this way. P.S. I find the seedlings can easily be moved to a new container/medium at virtually any stage of development, including newly sprouted radicles, as long as they are handled carefully.
What's your mix there, Maf? Looks like almost all sand. I'm using half sand half peat, but I think I'll cut back on the peat. Most of my losses come after transplanting, sometimes a very coarse mix damages the young stems. But it's not that high a loss rate. Last year the winter, and snails and mice, killed probably 80% of pots left outside, though. (I won't be doing that again soon). @Gomero, good germination with campbelli so far! -E
That's just the top coating/mulch. I usually use a mix of loam, peat, bark, perlite, grit in non-measured proportions.
I don't graft or grow from seed, with the exception of a few occasions. But I happen to know one of the best propagators in our area. He speaks very little English, but our passion for plants bonds us beyond any language. We have a very interesting way of communicating, that's not efficient by any stretch of the imagination, but it gets the job done. I have learned from him that mixing course sand in the soil mix is critical. The soil needs to be free draining and allow oxygen to the roots. He also uses a shallow free draining tray for starting, then goes to pots after the roots have become more developed. He also goes with more frequent misting, rather than an abundance of water less often with soil that retains the water. He is a natural, that has no formal training, just a lifetime of experience. He also uses this coarse sand and the above technique for propagating maple cuttings and all evergreen cuttings. He does things that many educated growers in the area can't do with success, or they simply say it can't be done. It's my understanding that lack of oxygen causes root rot (or what he calls sticky roots). Many times we associate this with water, because the water prevents the oxygen getting to the roots. So, when roots are young, thin, and under developed; it's very easy for the roots to be overwhelmed with a lack of oxygen. Very free draining soil which allows the roots to breathe is key to success in my opinion. As the roots develop, thicken, and become more diverse you can then pot up with a free draining soil mixture that can retain some water, to reduce the need for frequent misting. The presence of sand in the mixture is key, but less sand is required as the tree ages and the roots become more developed and larger in size. I think too many people feel an abundance of organic matter is needed to get the seed started. The seed starts to grow in sand using its own energy reserve. In his method, organic matter is not introduced until the seedling is removed from the tray into a pot. This cluster of sand is always present and undisturbed. The roots grow out into the surrounding mixture of sand and organic matter. Now that I think about it, the sand maybe sterile too, free from harmful bacteria, which may contribute to his high success rate using this method.
