Cactus Sunlight Requirements

Cacti and Succulents require sunlight to thrive but the amount and intensity vary widely depending on species. Where I grow the plants I sell, in the Sonoran Desert, our Summers are over 115°F for weeks at a time so shade netting is key for me to achieve the quantity of sunlight needed while cutting back its intensity for my non-native Cactus such as Trichocereus and my Succulents. 

I try ensuring my Cactus get 8 or more hours of sunlight. Some succulents can have healthy growth with less light than that but its still very important that they get plenty of direct sunlight for healthy growth and blooms.

Cactus can be sunburned which looks like this.

This can be caused by moving a shade acclimated plant to a sunnier spot too quickly. Sunburn can also occur if the specific plant simply isn't capable of the sun intensity its receiving. 

The alternative is too little sunlight, which will cause the plant to become etoliated. Etoliation occurs when the plant is searching for more sunlight, and can be described as weak, leggy growth with increased spacing between Cactus areoles and Succulent leaves. I will upload photos soon.