Arbutus: re-potting a temperamental arbutus

Hi,

I planted a couple arbutus seedlings into pots last summer, being VERY careful to ensure that the soil & drainage etc fit the plants' unusual & fussy needs (see http://soilslab.cfr.washington.edu/madrone/book.html), including 'seeding' the soil with arbutoid bacteria collected from around healthy trees. For no reason in particular, each seedling was 'seeded' with soil from a different adult tree. Unfortunately, I didn't assess the first arbutoid-source tree as well as I should have, and I now realise that it was actually infected with a canker &/or foliage fungus.

Sooooooo, since that seedling is clearly struggling (see my first and second posts about it here), I'm thinking about re-potting it into new soil with new HEALTHY arbutoids, but am wondering how to do it without upsetting the infamously fussy plant (a species that doesn't like to be disturbed once, much less twice in its lifetime). Ideally, I think it'd be best if I could remove the seedling from the pot it's now in, wash off all the soil from its roots, and then replant it in a new pot & new soil. If I weren't needing to remove the old soil, I could probably find a way to break the old pot inside the new one that kept the roots & soil relatively undisturbed. But since the problem is IN the soil itself, I don't think that'll be enough to rescue this plant or allow the new arbutoids to overpower the old ones.

So does anyone have an idea for how I could re-pot, clean & re-soil this plant without disturbing its roots more than necessary??

Thanks so much!!

 

On the one hand dryland plant susceptible to disease problems under moist conditions, on the other hand spontaneous seedlings pop up frequently in gardens and appear to thrive under irrigation regimes present there. Frequent watering that may be required when growing in containers may be basis for high mortality. Or, use/lack of use of fungicidal spray program may be critical factor, with sprayed plants holding up under regular watering. As always, total combination of factors in particular situation determines result.

Has been said to be possible to pull up wild seedlings in February, pick off leaves, pot up and refoliate under greenhouse conditions with good results.

 

But how do I repot the seedling I already have without disturbing it too much??

(ps: my minimal watering + no spraying works well for the 2nd seedling so I'm pretty sure the problem comes from fungi in the 'seeding' soil that I used for the 1st)

Thx!