Sawara Cypress - what is wrong with my roots?

[MrBonsai19]

I am relatively new to bonsai, and not sure what is the next step to help this tree recover its health. I am in northern california zone 10a. I purchased the tree in August for $15 USD, so it was a minimal investment but I would definitely like to learn why I have caused this tree to decline in health. I think it might be overwatering leading to fungus or mold in the roots, but I did read that Sawara 'Boulevard' cypress likes to stay moist and I have been trying to water with that in mind. I am not totally sure if this is a 'Boulevard' cypress or some other cultivar, but just going off my best guess. I let the tree dry out between waterings but not as much as I do for other conifers. Maybe that is the issue?

On 10/13 I created a mixture of 1tsp neem oil, 1 tsp insecticidal soap, 1 gallon of water, and I watered the tree with this solution. It did not respond all that well, the canopy has started sagging a lot, but my hope was the neem oil would address what looks like fungus to me in the roots. However now I am not sure if I have the right approach and would welcome any insight what's going on. Here is a more in-depth video recording of the issue as well:

IMG_1231.MOV

I would very much like to repot this tree and it is taking a lot of self-control to wait until end-of-winter next February in about 4.5 months. Is this a scenario that justifies a high-risk repot right away? Probably not, the tree does seem to be surviving but not all that well. It will probably limp along until February but I worry at that point it might be too unhealthy to repot anyway. Especially if the current issue continues to get worse if I cannot solve the problem.

Thanks for any help or insights!

 

[Shibui]

Fungus on roots is not always a bad thing. Some species of plants actually have association with some fungi that help feed them. Check out some pine threads where people go crazy about mycorrhiza and actually add it when repotting.
In many other cases fungi in the soil are breaking down organic matter and making it available to the roots as nutrients.
Occasionally we get bad fungi that can infect and kill roots but usually only when conditions favour the fungi and not the roots - eg overwatering.

Most of the photos show relatively healthy roots but a couple have blackened roots which is usually a sign of root rot. You can sometimes detect an off smell when that's happening.
While junipers of all types do not like to get dry they also don't tolerate having constantly wet roots. All in all, it's probably better to err on the dry side rather than too wet. Best to water really well to ensure the soil is fully wet when you do water but don't water again until the soil down deep is getting close to dry again. Sometimes that will be daily, sometimes once a week or somewhere in between. Depends on season, sun, wind, soil type, pot size, tree size, how long since last repot and much more. The only way to work it out is to check the soil moisture each day - not just the surface which will look dry while deeper is still wet. Need to check deeper down in the pot.

Neem is promoted as a cure all which will fix all manner of ailments but not sure how much of that is accurate. Allowing the roots to dry out a bit seems to deal with root rot just as effectively. There are also some good fungicides that have been tested to be effective that may help.

Repotting can help deal with root rot by removing infected parts but also providing better soil to replace what's caused the problem. Zone 10 is probably safe to repot at this time of year but if you are concerned about out of season repot you should treat with care (drier than normal) through winter and repot next spring.

 

[Wires_Guy_wires]

Neem is promoted as a cure all which will fix all manner of ailments but not sure how much of that is accurate

I know this one:
A couple (as in less than 10) pathogenic fungi are slightly (!!!!!!!) inhibited by pure neem oil. All 1000+ other pathogenic varieties of fungi are not.
Neem oil acts as an insect deterrent, sometimes as a toxin, but mostly as a deterrent.
Neem oil is as much a fungicide as tap water is. And whoever is promoting it as a fungicide should read through some literature; most studies show the surfactant being the inhibitor, and rarely the neem itself.

Adding soapy water + oils to the roots can be a bad thing for the roots. The root hairs rely on surface tension of water for proper gas and water exchange and soap tends to screw up that relationship. Oil does too. It's not always problematic, but when it is, it is. I believe it's better to prevent it as a whole.