Japonicas are more sensitive. Their leaves react earlier to the sun than sasanquas do up here. I also noticed a similar issue with a variegated hydrangea and its non-variegated one in my previous home. They were planted side by side and the variegated one had to be transplanted because the leaves suffered from the sun more.

It is absolutely true that camellia would have sunburn under direct sunlight. In California, I have to have shade cloth for growing quite a few camellias.

However I had a 46 days tour to almost 18 places of camellia plantation in China this year where mostly the camellias were growing openly without protection. Because the native land of camellia is humid, misty, cloudy, foggy or raining. I visited a place at Sichuan Province where a million of their traditional Chinese camellias, about 100 cultivars( C japonica) were growing openly on the hills. It is considered to be the largest camellia plantation in the world. The camellias are shipped to every place in southern China for landscaping purpose.

Here is a link that might be useful: {{gwi:509829}}

One more picture.

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Those pictures are incredible, longriver!

longriver, amazing photos and facts, thanks for sharing!

Oh yeah, my neighbor has camellias in full, all-day sun in Jacksonville, Florida. Has been there 15+ years. No mist, no clouds, no fog. Hot and humid. The camellias are huge.

Humidity might play a major function to preventing the sun burn. I also feel that moist soil helps. In California we are in dry season, the soil can be bone dry without timely watering. There are still many other factors such as very intense afternoon-sun, gentle breeze, -------.

I think shade (especially morning shade) is more important in winter than in summer in more Northern locations. Our summers are humid, hazy and generally good for camellias. However our winters are a bit too harsh for them and the sun makes it worse.

Here at Ottawa, zone 5A, I found that Japonicas are doing much better in more sun than less. I have 5 Japonicas, I had them under a tree before, they were having 3 or 4 hours morning sun. Then I moved them into a more sunny location this year with full sun till 4pm, then full sun again from 5pm. They are growing much faster and having constant growth flushes. Last year, they had only one growth flush.

I also have three Sasanquas, they are happy like a pig under all day sun. Doubled their sizes since I moved them from half day sun into all day sun location.