How much winter sun?

As you may know, this summer I finally got my cactus beds planted and even made them look better with a dry-stacked stone wall. I'm so happy to have these in the ground now, as last year they spent the winter on my deck in pots.

I had a few problems with pads rotting at the end of winter, but only those that were in contact with the soil -- the "child" pads up in the air were all fine. I expect that the soil in the pots just got too wet, something I'm hoping to avoid this year.

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I do have some doubts about my cactus beds, where I've mixed a good deal of pea gravel and sand into the soil though. I'm still not certain if the soil is well-draining enough, but I have another concern too: Will these plants get enough light during the winter?

Although this area gets full, blazing sun during the summer, it's in shade for most of the day in the winter, in the shadow of my neighbor's house.

So although they get reflected light on sunny days and may get some sunlight in the early morning and late afternoon, they won't catch the strongest rays of the day.

Does this matter? Do cactus and other succulents like Agaves need sunlight in the winter?

The few potted cactus I have left will stay under cover of the front porch this winter:

This will ensure that they don't get very wet -- they'll probably stay completely dry unless I water them -- but it means that they'll get very little light too. Will that be a problem?

It's a couple of Opuntia, a cholla (Cylindropuntia whipplei), and my little Yucca rostrata -- the cholla and yucca will probably get repotted this weekend. How much light do they need in winter?

Anybody with some experience or thoughts on this, please comment and hopefully ease my mind!

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