Hi, I have 2 japenese black pine seedlings about 1.5 years old now, and some of the needles is turning dark and brown. (the 2 pics thats attached is of both the trees), they stay outside, full sun. The soil that they are in now is a akadama and crushed silica mix. I stay in South Africa it's the start of autumn now. I give them fertilizer every 2 weeks during the growing season and only water when the soil starts to dry out. Anyone know what can cause this?
Japanese black pine seedling problem
- Thread starter sarcpilot
- Start date
Paradox
Imperial Masterpiece
Looks like it could be a fungus. Banding on the needles is most likely needle cast.
Unfortunately with needle cast, you need to treat preventatively for because it infects the needles the year before you see any evidence of it.
Is the area you in pretty humid?
Also please put your location on your profile
A lot of bonsai information and advice is location dependant. It helps us to know where you are to give the best advice without having to ask every time.
Unfortunately with needle cast, you need to treat preventatively for because it infects the needles the year before you see any evidence of it.
Is the area you in pretty humid?
Also please put your location on your profile
A lot of bonsai information and advice is location dependant. It helps us to know where you are to give the best advice without having to ask every time.
River's Edge
Masterpiece
Does not look like needle cast to me, looks more like the seedlings are drying out or affected by the strength of fertilizer being used! the mix looks like it drains very well so I would be inclined to increase the watering and be sure to water thoroughly. Water until it is draining freely out the bottom and running clear. This ensure the flushing of extra salts and provides fresh air and moisture levels in the pot. Seedlings that size do not have extensive root systems and require more frequent watering than established saplings for example. If you are not doing so use a 1/2 strength dose of fertilizer and switch to once every two or three weeks to see if that makes an improvement as well. These are general suggestions without the benefit of understanding your specific care routines. The other aspect could be a very windy/dry location which would speed the drying and would be improved by the two modifications suggested above.
Shibui
Imperial Masterpiece
Agree with @River's Edge
Internet talk of pines having problems with overwatering has many new growers scared to water so trees dehydrate. Silica/akadama mix probably does not hold much water so may be prone to getting drier than anticipated. Problem appearing after summer is probably related.
Please consider the possibility the trees have dried out a bit too much, even occasionally. Symptoms don't usually appear for weeks after the event so we've often forgotten about the long weekend when we forgot to water, etc.
Internet talk of pines having problems with overwatering has many new growers scared to water so trees dehydrate. Silica/akadama mix probably does not hold much water so may be prone to getting drier than anticipated. Problem appearing after summer is probably related.
Please consider the possibility the trees have dried out a bit too much, even occasionally. Symptoms don't usually appear for weeks after the event so we've often forgotten about the long weekend when we forgot to water, etc.
Thanks @River's Edge and @Shibui
I now notice that the one is getting worse and one of the other is also showing similar symptoms
There was a time in summer that they got quite dry tho
I now notice that the one is getting worse and one of the other is also showing similar symptoms
There was a time in summer that they got quite dry tho
