How Much Sun does A Cactus Need ?


Imagine you are rying to grow cactus plant indoors. The first thing that you want to know is to find how much light does a cactus need? Given the fact that these are desert plants, it is quite obvious that they would need more light or sun. In this post, we will try finding what amount of sun would you need for growing cactus efficiently.

Under most of the ideal conditions, a cactus will need at least 4 hours of light per day. Howevr, they would prefer around 12 hours of light. Some species of cactus prefer low light while a few others prefer a lot of light. However, it may be noticed that they may also face sunburn issues if you provide it with too much light. 


How much sun does a cactus need?


Cactus generally does well with the bright light. You would find it working best with a lot of bright light and full sun. In most of the situations, you would find that it would do well 6 hours of light everyday. It may be noted that cacti will sustain more sun than the succulents. It may also be noted that larger cacti would require more light than the the smaller ones. 

Cacti are found in desert areas mostly and like to be in the sun. Cacti have learned well to survive in the scorching heat. They may need sunlight at least from  4 to 6 hours and a maximum of 14 hours. They can grow best in bright light, high temperature, and less water. Some of them may survive in less light and humidity. Insufficient light may make cacti pale and they show discoloration. It can also affect the growth of cacti plants. These symptoms can be reversed by putting the cacti plants in the sun. Once they start receiving the sunlight again, they become healthy.

Photo – Britannica.com

How Much Water Does A Cactus Need?


You should water the cactus only when the potting soil is at least 90% dry. In the spring and summer season, you will water the cactus at least once in a week. In the winter season, you can water your cactus every 4 to 6 weeks. The exposure to sunlight is one of the prime factors that would decide the amount of water you would need. You may add water two to three times a week. 

While growing cactus, it is important to know how much water it requires. Proper watering will support the plant in growth, blooming, and also in developing fruits. When we talk about cactus, desert areas come to our minds. Cacti not only grow in desert areas but some of them even grow in tropical rainforests. How much water a cactus need is also important like how much sun does a cactus need.

When you bring a cactus plant home you should know to properly care for it. The first step in this aspect is to water a cactus plant. One must keep in mind these rules while watering a cactus plant. 

Photo – familyhandyman.com

How Many Times a Cactus Should be Watered?

Different species of cactus have different water requirements. One unique thing about these plants is that they can survive long without water. If we totally neglect the plant in this regard, it can turn yellow or pale. Soil should be dry between the waterings. It will prevent the plant from waterlogging and rotting of the root. Watering also depends upon how much sun does a cactus need.

March to September is the growing season and cacti need regular fertilizers and watering. Watering them once a week is sufficient. The top soil should be completely dry before watering it next. Put a stick into the soil and if it comes out dry, it is ready for  watering. Look for the signs if the plant is overwatered or underwatered. An overwatered cactus looks plump and will rot afterwards. An underwatered cactus becomes pale and can dry eventually.

During the winter season, when the cacti become dormant with less sun and long cooler nights, the water requirements also become low. 

Whether the cactus is small or large

As the growth rate of smaller cacti is more, they need more water. Water them  more frequently. The evaporation of water from a large cactus surface is less due to small surface area to volume ratio. So a larger cactus needs less water as compared to a smaller cactus.

Water requirement also depends upon the type of soil

Always take a good quality potting mix to grow a cactus plant. Sandy, porous and pebbly soil which drains properly and has good aeration is best for a cactus plant. The soil should contain organic matter that keeps the cacti roots moist and also can dry quickly. This type of potting mix can be made at home too that will be economical.

Follow these steps to make a potting mix:

Mix equal portions of grounded fir bark and peat moss or coconut coir in a bucket or tub.

Mix two parts of potting mix and one portion of coarse builder’s sand. This type of potting mix is good for tropical species as they retain more moisture than desert cacti. You can substitute sand with perlite, pumice or vermiculture.

For desert cacti, mix equal portions of sand and potting mix as the desert cacti don’t like the water retention soil. Instead of sand you can use perlite or pumice or vermiculture.

Mix properly so that there are no lumps in the soil.

The soil is ready for planting a new cactus. Water it thoroughly before plantation.

Types of Containers or Pots We Use

Water requirement also depends on the type of container we use. Containers are of different types ranging from plastic, terracotta, ceramic and metal to clay types.

  • Plastic containers: Plastic containers are very light and are of different designs that are very attractive and durable. One drawback of using plastic containers is that they don’t drain properly and quickly. Be cautious of watering the cacti grown in these containers otherwise, the roots can rot. Water the cacti grown in plastic containers less often to keep them healthy.
  • Ceramic pots: Ceramic pots are heavy and are durable. The unglazed pots are porous and absorb moisture from the potting soil. The glazed pots are not porous and don’t absorb moisture. Keep checking the soil for moisture to know when to water your cactus.
  • These pots are good for indoor plants and protect them against temperature changes. These pots can crack in freezing temperatures and are also costly.
  • Clay pots: These pots are cost-efficient and are porous. They are made from clay. They can drain well and come in different sizes and shapes. These pots are used widely due to easy availability.
  • Terracotta pots: Terracotta pots are made from clay and are available in all sizes and shapes. They are porous and drain water quickly. They are affordable and are ideal to grow cacti plants. These pots can also crack if exposed to extreme cold.
  • Metal pots: Metal pots  come in different sizes and shapes and are long lasting. They are not very ideal to grow cacti plants . They  are coated to protect against rusting.

Whether the cactus is grown indoors or outdoors also determines the watering

The cactus plant when grown indoors needs water once every ten to fourteen days during the growing season.  To avoid any dissolved salt from staying in the soil, proper drainage of water is important. How much sun does a cactus need can determine the watering requirement too.

The plants need less water during the winter season which is a dormant season for the cacti plants. Watering once every three to four weeks is sufficient in the winter season. Increase the water frequency if the cactus turns pale. In winters as we use heaters the air becomes dry and can affect the cactus plant. Place a water tray near the cactus to humidify the air and hence the cactus plant. You can also place a humidifier to keep the room moist. Similarly, a dehumidifier can be used to remove the excess moisture from the room.

Watering the outdoor cactus will be different as they are exposed to different conditions. The soil should be dry before watering an outdoor cactus plant.

Moisture meters can be used to check the moisture level. During the growing season, outdoor cactus plants can be watered once every seven to ten days.

During the dormant season, the cacti can be watered once every three to four weeks indoors. Watering the cacti in the morning is best for the plants.

If the cacti receive the direct sunlight, the rate of evaporation is more so water your cacti more often. The cacti placed under the shade or lesser sunlight will need less watering.


Cacti That don’t Need Sun


 Sometimes we think cactus can survive in the sun only. People often get confused as how much sun does a cactus need. Some of the cacti plants that don’t need sun are :

  1. Crown Cactus ( Rebutia )

It grows in clusters in the wild on the mountains and is native to South America. This cactus grows best in sunlight but can live indoors as well. It needs less water and is very resilient and adaptive.

Photo Source: World of Succulents
  1. Scarlet Ball Cactus ( Parodia Haselbergii )

These cacti are easy to care for and are small, round-looking cacti with many fine and straight spines.Red or yellow flowers grow on the crown of the cactus during the bloom. These are native to South America where they grow in moist environments.

 

  1. Zebra Cactus (Haworthia Attenuata)

A beautiful cactus that can survive well without sunlight. It is of small size and is a popular choice to grow it indoors. It has dark green leaves with horizontal stripes and spines along the edges.

  1. Christmas Cactus (Schlumbergera Bridge)

These have flat, spiny leaves and bright flowers that bloom in the winter season that gives them the name Christmas cactus.


How Much Sunlight do Succulents need?


Succulents are the plants that need sunlight to thrive. However, the succulents don’t grow well in the scorching heat. The reason for this is that the succulents are from semi-desert environments. Most succulents grow in low-lying areas and are shaded by taller plants. They are found in crevices, in nature and are protected from the sun or on hilltops, and are shaded by the rocks or boulders.

4 to 6 hours of sunlight is sufficient for succulents to keep them healthy. If the succulents do not receive enough sunlight they show elongation or etiolation and stretch to get more sunlight. The stem becomes weak and growth is also poor.

Intense heat can cause sunburn that can happen quickly or gradually. Brown spots on the leaves are the first signs of sunburn. It can be rectified by keeping the plants under the shade.


Does cactus need Sun?


Yes, the cactus does need sunlight. They would ideally need several hours of direct sunlight. However, it may be noticed that some cactus species may not be able to withstand direct sunlight. If you have a cactus with hairs, strong spines, or a large number of spines, you would find it needing more light. A plant with less spines and the plants belonging to the succulents variety may not need indirect sunlight. 

When you expose your cactus to sunlight, it should be done quite gradually. If you tend to expose the cactus to a bright sunlight all of a sudden, it may experience sunburn issues. Sunburn can severely affect the health of your cactus.


How Often to Water Cactus?


Cacti should be watered once the soil is completely dry. Monitor the plant and dryness of the potting mix before watering a cactus. How often to water cactus will depend upon a number of factors like temperature, humidity, weather, size of the cactus, and size of the pot.

Each cactus has different water requirements. Make sure to water thoroughly and the potting mix should be dry to water the cactus again.


Can A Cactus Get too Much Sun?


Yes, Cactus can end up getting too much sun. While a cactus does need a lot of sun, too much of it can damage the cactus. You would find a cactus under too much sun to get a bleached out look. They may also turn yellow or even turn greenish. A few other signs of too much sunlight can include droopy leaves, color fading and crumbling leaves. 

Cacti plants are drought resistant and store water in the stem. Although cacti plants are known as desert plants, some species cannot tolerate direct sunlight. Prolonged exposure to direct sunlight can cause damage as these species suffer from sunburn. It will result in permanent scarring and even death. Many species have developed a wide range of adaptations to survive in intense heat.

Slowly condition your plant to the intense sunlight before full exposure. Place them in partial shade and introduce them slowly to more and more sunlight till they get used to the sun and heat. Expose them to the morning sun when the heat is less and slowly introduce them to the afternoon sun.

By increasing the sun exposure gradually will avoid shocking the plant and thus prevent sunburn or permanent scarring.

Newly propagated cacti and shade-loving cacti are more prone to sunburn and damage whereas grey, blue or red cacti having spines grow well in the sun.


Can Cactus Survive Without Direct Sunlight?


No. a cactus cannot survive without direct sunlight. Any plant will need at least a minimal amount of direct sunlight. On a weekly basis, you would need at least 25 to 28 hours of direct sunlight per week. No plant will live with no direct sunlight. A complete lack of direct sunlight may not be the right option for a cactus to grow. 

Cacti like any other plants need direct sunlight. Insufficient light will not let the cactus bloom and it can get infected. Some species of cactus-like Christmas cactus are without spines and can survive for a shorter period without sunlight. But such plants also need lots of sunlight to grow and blossom. If the cacti plants don’t get sufficient sunlight, they become thin and can die.

When the plant is not getting sufficient sunlight, it can get elongated or etiolated. Etiolation is a process where the plants elongate or stretch towards the light. The plant will grow fewer spines and become weak and unhealthy. It occurs in any plant but is noticed more in cacti and other succulents. Once the plant undergoes elongation, it will remain as such throughout life. However, you can cut the elongated part. Once the wound is healed, the plant will resume normal growth.

During summers, when the days are longer, cacti grow well in such conditions.

In winters, the cacti plants become dormant. Their rate of metabolism slows down and the plants stop growing. Cacti plants produce seeds, fruits, and flowers during the dormant season. In winters cacti plants require less exposure to sunlight. 


The Concluding Thoughts


So, that should have given a good insight into how much sunlight does a cactus need. The crux of the matter is that a cactus does need enough sunlight and providing enough of it based on the individual plant requirement would help you out in getting the best possible sunlight. Check out the size, the spines and exact requirements of your cactus and provide it the required amount o sunlight.


FAQs


Do cactus need direct sunlight?

Cacti do need good sunlight to thrive. You need to provide them a bright space that is well lit. Your cactus does need at least 6 hours of sunlight on a daily basis.

Can cactus survive in dark?

No, cactus will not survive without sunlight. They do need regular and daily source of light. However, the amount of light will be dependent on the type of cactus. If your room has darker environments, you will need to provide artificial light.

Nikita

Nikita is a Succulent lover. She really enjoys planting and nourishing them. She loves to share information about various Succulents on this blog to aware people more about these awesome plants.

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