6 hours of morning and late afternoon sun is not harsh even in OK. Yes they need that sun. Not the midday sun but early and late sun. I'm not crazy about New Guinea impatiens but I had them once. I had planted them in pots which I had in the west and they got sun from noon on. They didn't do well so I moved them onto my front steps where they got 3 hours of sun in early morning and from about 4 PM until nightfall and they did very well

Thank you! When I said "harsh" I meant afternoon-evening sun. Well, I guess it's back to other Impatiens for my planter!

This year our club bought 50 liners of these for our fair display garden. We potted them up and had them in our greenhouse. We have never put up our shade cloth before May, but this year we lost 50% of the New Guinea Impatiens from two warm days in April. Nothing else in the greenhouse was damaged. It seems they are more sensitive than we imagined. Al

But how hot did it get in that greenhouse during those warm days, Al?

They do best with some sun, but morning or evening sun is best - they just don't seem to tolerate the strong afternoon sun very well.

In the greenhouse environment in young plants, light damage in N.G. imps is strongly related to watering. If you let them get too dry, to the point of wilt, and then combine that with too much sun, you may find the leaves will not recuperate and often fall off, leaving only the growth point. They struggle and often stunt and never do live up to their potential.

I've had to move them in the greenhouse situation as spring progressed, to the benches with the lowest direct light. They do need enough light to initiate good bloom however. Otherwise they'll have lush, tender foliage and not be highly budded.

They're fairly tough when mature but you do the dance to get them to that point. Filtered light is a good situation for them, morning/evening sun is also a good situation for them at most latitudes.

rhizo the greenhouse we have the use of, is located on a high school campus, with no one on site. We are located about 30 miles from the pacific ocean and a wind from the northwest off the ocean moderates the temperature. On occasion a wind shift to an easterly will result in a temperature increase of 20 degrees overnight. Al

I've never had any luck with them. I've tried the west side of my house with some dappled mid afternoon shade, but they still didn't bloom well for me. Too bad as I like the variegated foliage in particular....Maryl

I have mine in morning sun. But I am not looking for flowers. I grow them for the variegated foliage. My shade pots are all focused on foliage.

I haven't grown them yet in OK. Grew them many years up north--always put them in heavily dappled shade that turned to full shade. They did beautifully. I'm anxious to try them down here in OK, and they will HAVE to go in full shade, as we are a hot zone 7!

I had big pots of them all summer in full sun and part shade. As long as watering was attended to, they did fine.