Help; JBP bonsai brown needles

[Shibui]

Plenty of growers in Melbourne area use nothing but tap water with no problems.

 

[Haidr]

Plenty of growers in Melbourne area use nothing but tap water with no problems.

Copy. Thanks Shibui

 

[Haidr]

Hi @Shibui , regarding the Black pine bonsai, I had a quick look at the roots to check if I can spot any issues. Would you be kind enough to have a look at the pictures attached and let me know if you see any serious issues? The roots don’t smell like root rot. The only thing I’m concerned about is the tree is root bound. Should I wait for the spring season to repot it or I have to do slip potting now? Thanks in advance.

 

[Haidr]

Hi @Shibui and fellow bonsai enthusiasts, regarding the Black pine bonsai, I had a quick look at the roots to check if I can spot any issues. Would you be kind enough to have a look at the pictures attached and let me know if you see any serious issues?(Note; the tree was watered 10mins before the pictures) The roots don’t smell like root rot. The only thing I’m concerned about is the tree is root bound. Should I wait for the spring season to repot it or I have to do slip potting now? Thanks in advance.

 

[Shibui]

Those roots appear to be in excellent health. The white is mycelium of Mycorrhiza which is a symbiotic fungus that actually helps pines obtain nutrients. If there's any problems the mycorrhiza is the first thing to disappear. I can also see active white root tips so no problem with this tree's health as far as I can make out from the photos.
The pot is full of roots but probably not excessively pot bound yet. I think I would prefer to nurse it along through the remainder of summer and repot in Spring.
Due to the amount of roots you will need to water well through the hottest months. That means not just a pass with the hose. To get proper penetration you may need to water once, wait a few minutes and water again. The first watering only soaks in a few cm, leaving the centre of the root ball still dry, even if water is coming out the pot because most of it runs around the dry soil. Subsequent watering flows more easily into the damp section and then penetrates deeper to reach the centre of the roots. Japanese growers tell us to water each tree 3 times to do a proper watering. It is almost impossible to overwater a bonsai pot in our summer without sitting the entire pot in water for weeks on end.

If you decide to slip pot, please make sure you tease out the roots enough to make proper contact between new and old. Simply putting a pot bound root system in new soil can often cause more problems than it solves.

 

[Haidr]

Thanks for your detailed response mate. If I understand correctly there is no immediate need for repotting, I’ll wait for the spring just to be on the safe side. I’ll be careful with the watering and follow the directions you have shared. You have helped me save at least 3 trees of mine by now. Really appreciate your help. Attached are more pictures of the roots towards the end of the day. The tree was watered by soaking for 10mins early in the morning. Have a great weekend and Happy Australia Day in advance.

 

[Brian Van Fleet]

The yellow tips are on old needles, which can happen for a number of reasons: chemical, watering issue, roots got too hot. Whatever the reason, it likely happened before you bought it. Your tree looks healthy, above and below the soil. No need to repot it out of season; that’s just inviting trouble that you don’t have currently. From reading the thread, it appears you need a few more trees, because this one doesn’t need the level of attention it’s getting right now..

 

[Haidr]

Haha , thanks for your reply mate. This is my second black pine in last two weeks. Got altogether 10 bonsais now. Now since I got the peace of mind that the tree is okay I’ll let it be.