Most cacti do not like to be out in the blazing desert sun. But, ultimately, how much sun do cactus need? In general, go with a decent amount of sun exposure (6 hours a day) but with filtered light. They don’t like to have direct, hot sunlight on them as it leads to sunburn. But of course, there’s more to it than that.
Do Indoor Cacti Need Sunlight
Of course indoor cactus varieties need sunlight. While there are cacti that can survive quite well in shady conditions, there are none that will survive without any sunlight. You can give indoor cacti the sunlight they need with just a few easy steps.
How to Provide Light for Indoor Cacti
The easiest way to provide light for an indoor cactus is to just put the cactus in the window. The window, preferably a south-facing window, is a perfect spot for most indoor varieties. When you look at how much sun a cactus needs, they usually prefer about six hours of sun a day. But there are varieties that require more and varieties that require less.
Natural light is, of course, easier to come by and the preferred way of giving a cactus sun. Again, a nice window is the perfect spot for this. The window really should face south rather than north because, unless you’re in the Southern hemisphere, there will be more sun there.
If you just don’t have a good spot to put your indoor cactus to get good sun, you may need to get an artificial light for it. You can find grow lights in incandescent, CFL, and LED varieties. Be aware though, you need to get something actually labeled a grow light in order for your cactus to get the right type of light and therefore sun.
Can Cactus Survive Without Direct Sunlight
Absolutely your cactus can survive without direct sun. In fact, most cactus varieties will not tolerate direct and hot sunlight. Instead, most cactus prefer filtered sunlight for long periods. A light filtering window film or shade would work if you have an indoor cactus. Leaves from a tree would work well for a cactus outdoors.
Can Cactus Grow in Shade
There are some cactus varieties that require less sun than others. Most of them prefer a long time in the sun but with a filtered light to avoid sunburn. There are a few cactus types that will tolerate light shade though. These include most cactus types that are typically grown indoors such as aloe and zebra cactus.
Can Cacti Get Too Much Sun
Absolutely cacti can get too much sun. The issue is when the sun is directly on them, unfiltered, for a long period of time. There are several different presentations for a cactus that has gotten too much sun. To fix a cactus that’s gotten too much sun, you need to get the cactus out of the sun.
For the most part, once a cactus has gotten too much sun, and has been damaged by it, that damage can’t be repaired. The cactus will show scars of that damage for the rest of its life.
Sun stress on a cactus is not always a bad thing. This is the first stage of a cactus receiving too much sun. The cactus will turn different colors on the leaves to indicate that it is stressed. While sun stress isn’t a bad thing, and it is necessary for some cactus blooms to form, it is the first stage of a cactus getting too much direct sunlight.
When a cactus is sun burned, the skin of the cactus turns first a dark yellow, then a pale yellow, and finally a white color. The farther along the cactus progresses down that pattern, the more likely it will die of the damage. The flesh will always have an off-color to it, even if it is rescued from the sun, but the plant may live.
Sun scald is the final stage of a cactus receiving too much sun. The skin of the cactus will dry out and turn a scaly brown. This scar will be permanent. A cactus that hits this stage, depending on the size of the sun scald, may or may not be able to be saved.
We all think of a cactus as a desert plant when we wonder how much sun a cactus needs. But in reality, most of them don’t tolerate direct sun for long periods of time. Make sure that your cactus can tolerate your sun situation before planting it. If it shows signs of sunburn, make sure to move the cactus immediately.