How much sun exposure do succulents need?
It depends on the climate, locale, and type of plant. Along the coast of California, from the Bay Area south, most succulents are fine out in the open year-round. Inland, it's a different story; most succulents will need some sun protection in summer especially in the afternoon. But often all that is needed is the right microclimate, such as a lacy tree canopy. Incidentally, even in their native habitats, young cacti won't tolerate open exposure. They grow in the shade of nurse plants until they're large enough to handle the rigors of the desert.

Actively growing succulents do best with full spectrum light that is bright and diffused—beneath shade cloth outdoors or (if in a greenhouse) translucent white plastic. (Optimal light is when shadows are fuzzy, not sharp.) Dormant succulents don’t need a full spectrum light source (fluorescent is fine if you’re overwintering them indoors).

Aim to keep soil about as moist as a wrung-out sponge. About once a week should do it. Water thoroughly to soak the roots and flush salts. For succulents in containers, that means until water drips out the bottom of the pot.

Water more during hot, dry spells and less or not at all during periods of high humidity, cool temperatures and rain.

Also, the fatter the succulent or the fleshier its leaves, the more water it stores in its tissues and the less water it needs (and will tolerate). Cacti in general are less tolerant of overwatering than smooth-leaved succulents.

Aim to keep soil about as moist as a wrung-out sponge. About once a week should do it. Water thoroughly to soak the roots and flush salts. For succulents in containers, that means until water drips out the bottom of the pot.

Water more during hot, dry spells and less or not at all during periods of high humidity, cool temperatures and rain.

Also, the fatter the succulent or the fleshier its leaves, the more water it stores in its tissues and the less water it needs (and will tolerate). Cacti in general are less tolerant of overwatering than smooth-leaved succulents.