Japanese maple (Acer palmatum) from seedling

[bugnurd]

I’m starting individual threads for each of my trees to track their growth, development, and work. Here is my Japanese maple. Not sure if a variety can be determined, please let me know if you recognize it.

In spring of 2022, I pulled up three newly sprouted seedlings from the yard and threw them in a small pot with some garden soil. They grew a little that year, and ended up surviving the winter in the garage. Here they are in May 2023.

 

[bugnurd]

During 2023, they suffered a bit. Grass and weeds overtook them in the pot, and they struggled to compete. Two of them died. Here is the lone survivor in September 2023. It put on little to no actual growth in 2023.

 

[bugnurd]

April 2024… the terminal bud started to elongate, so I repotted it. The garden soil it was in was full of weed and grass roots. The seedling roots were not very abundant. I clipped off a tiny bit of the taproot, and potted it in a small pot with bonsai soil. I’m hopeful that it responds well this year and puts on some good growth, both above and below the soil line.

 

[Gabler]

I don't know where you're from, since you haven't completed your profile yet, but here in the U.S., Japanese maples are invariably garden/landscape trees, which means they're often selected from dwarf or even miniature cultivars, which are weaker than their wild-type counterparts. Even larger cultivars can sometimes be weak when they aren't grafted onto wild-type rootstock. I've found seedlings from dwarf trees are also weak, since they carry their parents' weaker genetics. Add on top of that the fact that a pot has limited space for root growth, and it's not surprising that a seedling from an unknown variety of Japanese maple would be easily choked out by weeds. I likewise learned the hard way that it's very important to stay on top of the weeds that pop up in pots. Pull 'em out as soon as a little bit of green appears on the surface.

 

[coltranem]

Any time you grow a seedling it will just be plain Acer palmatum. Named cultivars are clones of each other. In some cases the seedlings will have very similar traits to the parent other times they won't.

Seedlings need appropriately sized pots. It is good that you put it in well draining soil but I think that new pot is still too big. I am not sure what size tree you want to grow this into but I'd start with a 4 inch nursery pot and move up in size as it grows. The bigger tree you want the more you will eventually up pot over the years. Or maybe put it in the ground even.

 

[bugnurd]

I don't know where you're from, since you haven't completed your profile yet, but here in the U.S., Japanese maples are invariably garden/landscape trees.

I just updated my profile, thanks for that reminder. I’m in New Hampshire. The seedling likely came from a neighboring yard that has a large, mature Japanese maple in her backyard.

 

[The Warm Canuck]

Duplicate, see below

 

[The Warm Canuck]

Any time you grow a seedling it will just be plain Acer palmatum. Named cultivars are clones of each other. In some cases the seedlings will have very similar traits to the parent other times they won't.

Seedlings need appropriately sized pots. It is good that you put it in well draining soil but I think that new pot is still too big. I am not sure what size tree you want to grow this into but I'd start with a 4 inch nursery pot and move up in size as it grows. The bigger tree you want the more you will eventually up pot over the years. Or maybe put it in the ground even.

Not a 2" first? It's fine to go right to a 4"? Just asking, I have a few hundred to pot up.

 

[bugnurd]

I am not sure what size tree you want to grow this into but I'd start with a 4 inch nursery pot and move up in size as it grows.

Not really sure yet. That’s good to know for the future, but I’ll just see what happens in this pot this year since it’s already potted up.

 

[coltranem]

Not a 2" first? It's fine to go right to a 4"? Just asking, I have a few hundred to pot up.

It depends on the size and mix a little bit. My approach has been to plant the seeds in a flat or pot and then move to pots year two. At that point most can go into a 4 or even a 6. I make clumps at that point too so it reduces the amount of pots or matbe some proto-forests. A few runts might go into something smaller if I want to go a mame route.

 

[The Warm Canuck]

It depends on the size and mix a little bit. My approach has been to plant the seeds in a flat or pot and then move to pots year two. At that point most can go into a 4 or even a 6. I make clumps at that point too so it reduces the amount of pots or matbe some proto-forests. A few runts might go into something smaller if I want to go a mame route.

That makes sense why you go to bigger pots. I know others remove them from the large flat immediately once the first set of real leaves harden off, trim the taproot and transplant to individual pots, which is why a smaller size may be used.

 

[Gabler]

Seedlings need appropriately sized pots. It is good that you put it in well draining soil but I think that new pot is still too big. I am not sure what size tree you want to grow this into but I'd start with a 4 inch nursery pot and move up in size as it grows. The bigger tree you want the more you will eventually up pot over the years. Or maybe put it in the ground even.

Not a 2" first? It's fine to go right to a 4"? Just asking, I have a few hundred to pot up.

Not really sure yet. That’s good to know for the future, but I’ll just see what happens in this pot this year since it’s already potted up.

I've found that when seedlings are in a large pot—big enough that they can't use up all the water in the pot in just a few days—they tend to be weak and develop poor root systems. I've heard a number of different explanations why, but, regardless, the consensus is that trees grow fastest when started in a small pot and then up-potted as they grow, using a new pot twice the size of the old at each repot. That's part of the reason nursery growers don't start out their trees and shrubs in gigantic pots. Instead, they start with seedling trays, and they work their way up to a big pot.

For a bonsai hobbyist, it's not essential that the pot is the perfect size. Repotting often adds extra work. You can overpot a seedling, and it will be fine. I start seeds in a box and move the seedlings straight into half-gallon containers the following spring, where they'll stay for two to four years, depending on the species and its growth rate. I just keep an eye on them to ensure I'm not overwatering, and they grow reasonably fast, even if not optimally fast.

 

[coltranem]

That makes sense why you go to bigger pots. I know others remove them from the large flat immediately once the first set of real leaves harden off, trim the taproot and transplant to individual pots, which is why a smaller size may be used.

There are lots of ways to skin a cat.

 

[The Warm Canuck]

I've found that when seedlings are in a large pot—big enough that they can't use up all the water in the pot in just a few days—they tend to be weak and develop poor root systems. I've heard a number of different explanations why, but, regardless, the consensus is that trees grow fastest when started in a small pot and then up-potted as they grow, using a new pot twice the size of the old at each repot. That's part of the reason nursery growers don't start out their trees and shrubs in gigantic pots. Instead, they start with seedling trays, and they work their way up to a big pot.

For a bonsai hobbyist, it's not essential that the pot is the perfect size. Repotting often adds extra work. You can overpot a seedling, and it will be fine. I start seeds in a box and move the seedlings straight into half-gallon containers the following spring, where they'll stay for two to four years, depending on the species and its growth rate. I just keep an eye on them to ensure I'm not overwatering, and they grow reasonably fast, even if not optimally fast.

Sorry, I may be misunderstanding you but it seems your saying that over-potting creates weak roots, but that it's not something Bonsai hobbyist need to worry about?

I understand that sometimes it's just getting into the weeds and some things may be optimal but maybe not always necessary.

 

[Gabler]

Sorry, I may be misunderstanding you but it seems your saying that over-potting creates weak roots, but that it's not something Bonsai hobbyist need to worry about?

I understand that sometimes it's just getting into the weeds and some things may be optimal but maybe not always necessary.

I'm saying there's a room to compromise on pot size just a little bit. I don't put tiny seedlings into five-gallon pots, but I don't want to repot every year, either. I use pots just big enough that I can squeeze two to three years out of them. If I overestimate the pot size a little bit, or if it's a slower growing species, I might get four years before I need to repot. I use one-gallon grow bags, and I cuff them down to be a wide, shallow half-gallon pot.

 

[Shibui]

Not a 2" first? It's fine to go right to a 4"? Just asking, I have a few hundred to pot up.

I routinely transplant seedlings to 4" pots right from the seed tray so some are even smaller than the one in this thread. Really big pots can be a mistake but 4" seems to be OK. As @Gabler has replied, a reasonable sized pot allows room for good growth while not overwhelming the small tree. I find that pots smaller than 4" dry out wat too quick and don't have enough soil so growth suffers through summer. Then, at some stage, you need to sort out the tangled roots where they've coiled around the small pot.
If you're aiming for smaller sized bonsai the smaller pots might be useful in limiting internode length while the trunk is developing and they will definitely save some space but in general go a bit bigger for better growth and survival rates.

 

[The Warm Canuck]

I routinely transplant seedlings to 4" pots right from the seed tray so some are even smaller than the one in this thread. Really big pots can be a mistake but 4" seems to be OK. As @Gabler has replied, a reasonable sized pot allows room for good growth while not overwhelming the small tree. I find that pots smaller than 4" dry out wat too quick and don't have enough soil so growth suffers through summer. Then, at some stage, you need to sort out the tangled roots where they've coiled around the small pot.
If you're aiming for smaller sized bonsai the smaller pots might be useful in limiting internode length while the trunk is developing and they will definitely save some space but in general go a bit bigger for better growth and survival rates.

I'm sold, I'll go with 4"ish.

 

[Bonsai Nut]

It depends on the size and mix a little bit. My approach has been to plant the seeds in a flat or pot and then move to pots year two. At that point most can go into a 4 or even a 6. I make clumps at that point too so it reduces the amount of pots or matbe some proto-forests. A few runts might go into something smaller if I want to go a mame route.

I do something similar, but it depends on the tree species. For weaker / smaller trees like Japanese maple or princess persimmon, I sow a ton of seeds in an Anderson flat and let them grow for two years. In the spring of the 3rd year they will be 4" - 6" tall and I move them into 1 gallon nursery pots.

Bigger trees - or trees that come from large seeds, nuts or acorns, I will typically move into a 1 gallon pot in the spring of the 2nd year (oaks, walnuts, chestnuts, etc).

 

[The Warm Canuck]

I do something similar, but it depends on the tree species. For weaker / smaller trees like Japanese maple or princess persimmon, I sow a ton of seeds in an Anderson flat and let them grow for two years. In the spring of the 3rd year they will be 4" - 6" tall and I move them into 1 gallon nursery pots.

Bigger trees - or trees that come from large seeds, nuts or acorns, I will typically move into a 1 gallon pot in the spring of the 2nd year (oaks, walnuts, chestnuts, etc).

I would think that they'd get pretty crowded in the flats?

 

[Bonsai Nut]

I would think that they'd get pretty crowded in the flats?

Yeah they are crowded. I end up with about 50ish per flat. But after two years it is still pretty easy to separate them and pot them up.