Most succulents need sunlight, so they are able to preform photosynthesis and grow well. How much sunlight will depend on the species of succulent and time of the year. Some succulents can even die due to lack of sunlight.
The amount of sun succulents are exposed to will influence many things such as growth rate, thickness of leaves and stems, colour and hardiness.
I grow hundreds of thousands of succulents every year and have seen first hand how different species of succulents react to light changes and what happens when they do not get enough sun. The below advice is based on my nearly 10 year experience of running my own succulent nursery.
Can succulents survive without sunlight?
Some succulent species can survive and even grow without any sunlight but they are in the minority. Succulents need for the sun is perhaps best demonstrated by them stretching towards it when they are in too much shade.
In nature there are succulents that are found in shaded areas and even tropical jungles. These succulents (we will have a look at them in more detail below) generally do well in shaded areas but even they will need a bright spot to grow. The overwhelming majority of succulents grow in exposed areas in the wild and will only grow well if they are directly exposed to the sun for at least part of the day.
Just how much sunlight succulents need will depend on the species. Some will happily live with only 2-4 hours of morning sun while others require almost all day exposure. Having said that it is also important to keep heatwaves and extreme weather in mind. During very hot days direct sunlight, when the sun is very strong, can easily kill succulents, especially when they are young or not well established. We have an article on how to protect succulents during a heatwave.
What happens to succulents that do not get enough sun?
When a sun loving succulent is put in shade it will start growing pale with larger leaves and the stalk will begin elongating. Some succulents such as the sempervivum will start growing from the middle in search of sunlight. Others will grow leggy with leaves spread out on the stem. As the stem is also weakened, the leaves will force it to bend.
The whole growth will become distorted and less compact, plants will not spread as much, offsets will be scarce, and it is unlikely flowers will appear.
A more worrying ‘side effect’ of not enough sunlight is disease. There is a good chance some succulents will be more susceptible to fungus, mould, rust and rot. Eventually, many succulents that are in complete shade without even a bit of sunlight tend to die off.
Which succulents cannot survive without sunlight?
Crassula (some species can live in shade)
Hybrids of the above (Sedeveria, Graptoveria etc.)
Quite a few others would have tough time surviving without any sunlight whatsoever. It would be difficult to name every single succulent that will not survive without sunlight, though it is safe to assume most wouldn’t.
The genera named above are some of the most popular and recognizable. While some species within these genera could potentially survive without any sun, they would not grow and look as they should.
Which succulents can survive without sunlight?
Crassula (only some species)
Senecio (only some species)
Pretty much all the species within these genera (unless stated otherwise) should be able to survive without any sunlight and, as a matter of fact, they dislike being exposed to strong afternoon sun during warmer months.
There may be a few more species of succulent plants that will survive without sunlight, but the above mentioned are plants we grow at the nursery so I know for sure they will live without exposure to direct sunlight.
However, to be able to live, they will still need a very bright spot. Even with these shade-tolerant succulents there may be some distortion of growth and certainly loss of colour , especially in a plant like the very popular Ceropegia Woodii Variegata which has a pink variegation if it is exposed to enough sun.
As an example of just how much difference sun exposure makes, even to shade tolerant succulents, below i have two photos of Gasteria Banded Pearls. One of these plants is grown in a greenhouse with 50% shade factor. The other is indoors, in my bedroom and has been there for the last 3 years. The indoor Gasteria has not grown at all, other than stretched its leaves in search of light. There have been no offsets & no flowers on this plant either. It is in a fairly bright spot about 1m from a large window. The difference is staggering and demonstrates the importance of even a little sunlight for plants.
Can succulents grow indoors without direct sunlight?
Only a few select species of succulent can grow indoors without direct sunlight. They will still need plenty of bright light to survive. Without direct sun the growth will be very slow and shape of the plant can change.
I would recommend that only succulents from the above genera are grown indoors as others will find it difficult to stay alive. We have an article on best indoor succulents and best hanging indoor succulents that also name species that are best suited for a life inside a house.
There is, however, a way of growing any succulent indoors and that is with help of plant growing lights. For sun loving succulents to grow under these lights they will need to emit a spectrum of light suitable for succulents. Unfortunately, it is unlikely the cheap growing lights found on ebay or amazon will do the trick.
It is good to remember that more light a plant has indoors, the better it will grow.
In conclusion succulents, like other plants, need to get some sunlight to grow and preform photosynthesis. The amount of sunlight necessary can vary for different species and some succulents are even able to live without any sunlight but their growth will be slow or can stop altogether and the appearance can also differ from plants that do receive some sunlight.
If a succulent is kept in complete shade there is also risk of disease and rot which mostly affect sun loving succulents such as echeveria.
Succulents are best suited to a life outdoors and will always grow better in plenty of light.