summers outside-more harm than good?

[Subrosa]

Originally Posted by Fairorchids

While certain genera do well in full sun:

• They can only go directly out in mid/late April, and ideally they should go out during an overcast period.
• If you move them out later in the season, you must harden them in shade first (in 1 or 2 steps).
• In the Cattleya group, only Laelia anceps and reedstem Epidendrums can handle full sun. Other species and hybrids should be in light shade (I suggest 35% shade cloth).

I keep C. dowiana, C. trianae, and C. aclandiae in full sun as well, after acclimation. For what full sun in PA is worth.

[Roberta]

Originally Posted by Subrosa

I keep C. dowiana, C. trianae, and C. aclandiae in full sun as well, after acclimation. For what full sun in PA is worth.

The "after acclimation" part is the critical piece... moving the plants into increasingly bright light gradually. Similar to people... a day out on a Florida or Hawaii beach on the first day of vacation after spending winter indoors is an invitation to a very painful sunburn. Expose gradually and don't forget the sunscreen (shadecloth?)

"Full sun" is also relative... the number of hours of sun (and intensity) depends on trees, and orientation of one's yard as well as latitude. I learned that the hard way taking Andy's Orchids tags literally... A plant labeled "FS" toasted for me. A trip to Andy's told me why - the nursery has lots of big, mature trees that cast shade at various times of day so "full sun" duration is only a few hours in even the brightest areas. My yard faces east-west, with no trees in the middle. so in summer there's blazing sun from half an hour after sunrise to half an hour before sunset. Even "full sun" orchids get light shadecloth.