how to? Growing Rhododendrons on Clay Soil on VI

A friend of mine has a number of pots of rhododendrons which he intends to plant on his small acreage near Courtenay, Vancouver Island, but he has a number of constraints which seem to present some real challenges:
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"The soil here is naturally acidic leftover from the majestic forests that once grew, my soil tested at 4.9. The composition is fine clay probably a rock flour deposited by glacial action and now packed hard about 8" down. The upper layer is former forest humus mixed with the clay broken up by root action over the millennia. Saturated with rain it can become a thick pea soup if disturbed.

"Other problem is it leaves plants with wet feet, most don't like that so have to improve drainage."

As well as that, the house location is very sunny, although he has some forest-edge nearby.

He also writes: "I know the Rhodos are suffering from living in pots as we waffle over where and how to plant. Keep changing minds about location and what to do with the ground so appreciate your input. Several of the locations considered were subject to considerable sun and thus reconsidered. Current considerations are under firs but will require considerable soil modification. Was thinking of a shallow trenching refilled with manure and fir bark mulch as I have a lot - perhaps tons of manure, bark mulch not so much - of both."
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We used to grow rhododendrons in Vancouver, in acidic soil with partial shade. The rhododendrons grew very very well there—so I'm familiar with some aspects of caring for them—but my friend's location and soil type are very unfamiliar to me.

Advice would be appreciated. Should he not go ahead at all; or should he mix in a huge amount of peat; or —?—

Thank you.

 

Why not get involved with the Cowichan Valley Rhododendron Society - an excellent group affiliated with the ARS? Their members have undoubtedly encountered similar challenges. http://cowichanrhodos.ca/

 

I agree with suggestion above - join the club!

--- also - Milner Gardens: this is quite close to your part of eastern Vancouver Island - have you been there yet to view? Perhaps some inspiration and education opportunities
Overview | Milner Gardens & Woodland

I don't have direct expertise on your question for your friend with clay soil in comox area

- it sounds like a LOT of soil amending.

however -

and I know this is late to be asking (time elapsed from your original post) - are there overhead canopy trees? Is there a watering system already in place? ---- they need some shade for sure. It pains me to see people putting these things along the driveway (or front lawn etc) of these new scraped clear subdivisions out here in west BC!

and in my experience of moving to a new garden in this similar Georgia Strait region, they won't do well under already established cedars - tho, it depends, as the way they grow naturally in Manning Park BC (provincial park on Hope Princeton) is - under cedars tho in an open forest setting, and long-established.

it may well be touch-and-go for a while for these rhodos and lots of ICU rhodo care for a few years til established.