Do succulents like acidic soil? The answer is that it depends on the type of succulent. Some succulents prefer slightly acidic soil, while others prefer neutral or slightly alkaline soil.
Being such a diverse group of plants originating from many areas of the world, succulents have evolved to survive in different conditions. As you would expect, there is no one-size-fits-all answer to the question, ‘Do succulents like acidic soil?’.
Succulents are one of the most popular types of plants, and for good reason. They’re easy to care for, they come in a wide variety of shapes and sizes, and can brighten up any space.
Succulents are characterized by their thick, fleshy leaves and ability to store water. They have evolved to thrive in arid and semi-arid regions, making them excellent drought-tolerant plants. They are a diverse group of plants originating from different climates and parts of the world. You would expect, therefore, that they might have different needs for their soil and growing conditions.
Read on and discover if the acidity level of the soil is important for succulents and cacti.
What is Acidic Soil?
What is meant by the phrase ‘acidic soil’? It might bring to mind scenes from movies of toxic dumps spewing green smoke. But it’s not like that at all.
Acidity refers to the pH level of the soil. pH is a measure of acidity or alkalinity. It is measured on a scale of 0 to 14, with 7.0 being neutral. Values below 7 indicate acidity, while values above 7 indicate alkalinity.
Soil pH plays a crucial role in plant health as it affects nutrient availability and microbial activity.
Most soils will be fairly close to a neutral pH and will not be strongly acidic or strongly alkaline. For example, you wouldn’t expect an acid burn from touching normal soil.
What pH Level Do Succulents Like?
Most succulents will generally thrive in soil with a slightly acidic to slightly alkaline pH range of 6.0 to 7.5. Most commercially available succulent-soil mixes and cactus-specific soil mixes will be within a suitable range for your plants.
In fact, soil acidity and alkalinity is probably not something you’ll want to worry about if you grow your succulents just because you like them and they look good. Other issues, such as over or underwatering or incorrect light conditions, are more likely to hamper the growth of your succulent than soil acidity. Ensuring the soil is well-draining and that you use a pot with drainage holes is just as important.
If you stick to potting mixes that are designed specifically for succulents and cacti, you should be just fine. These soil mixes are readily available online and from garden centers and are not expensive.
If you are serious about your succulents and their blooms, you may wish to research the exact needs of your individual plants and tailor their soils accordingly.
Having said that, while succulents can tolerate a range of pH levels, extremes on either end of the scale can cause problems.
Effects of Highly Acidic Soil on Succulents
As we said previously, soil pH plays a crucial role in plant health as it affects nutrient availability and microbial activity.
Highly acidic soil can adversely affect succulents by hindering nutrient uptake. Acidic soil reduces the availability of essential minerals like nitrogen, phosphorus, and potassium, which are vital for plant growth.
In extreme cases, excessively acidic soil can cause stunted growth, yellowing leaves, and a generally unhealthy plant.
Reasons Why Some Succulents Like Acidic Soil
Succulents that prefer slightly acidic soil have evolved to adapt to the nutrients and conditions that come with living in that environment. For example:
- acidic soil helps make essential nutrients like iron, manganese, and zinc more readily for uptake by the succulent’s roots
- acidic soil can inhibit the growth of certain bacteria and pests
Thus, succulents that prefer acidic soil have developed mechanisms to efficiently use the nutrients that are most available and to thrive in these specific conditions.
What Can Affect The Acidity of Plant Soil?
If you’ve purchased a potting mix specifically for succulents and cacti, you should be good to go. But you should note that some environmental factors can change the acidity of the soil over time.
Fertilizers can significantly affect soil pH. Different types of fertilizers have varying pH levels. For instance, nitrogen-based fertilizers tend to lower soil pH, making it more acidic, while lime-based or calcium-rich fertilizers can increase soil pH, making it more alkaline. Regular over-application of fertilizers or using the wrong type of fertilizer can gradually shift the soil’s pH balance.
If you choose to apply fertilizer to your succulents, use a succulent or cactus-specific fertilizer and use it as recommended on product packaging. It will have been blended with an optimal balance of nitrogen, potassium and phosphorus for succulent plants.
If you use water straight from the tap for your plants, it may, over time, affect the pH level of the soil.
Some water sources, particularly those with high mineral content, can be alkaline or acidic.
This is sometimes referred to as ‘Hard’ or ‘Soft’ water. Hard water is more alkaline, while soft water is either neutral or slightly acidic.
Over time, consistent use of water with extreme pH levels can gradually alter the pH of the soil.
You can test the pH level of your tap water, and if it is too acidic or too alkaline, consider using filtered or distilled water for your houseplants.
Alternatively, collect rainwater, which generally has a neutral pH.
Overwatering or Underwatering
Improper watering practices can indirectly affect soil pH.
Overwatering can leach nutrients from the soil, resulting in nutrient imbalances and potential acidity.
On the other hand, underwatering can lead to the accumulation of salts in the soil, increasing alkalinity.
Striking the right balance by watering and allowing the soil to dry out between watering sessions can help maintain a stable pH level.
Metal containers can potentially affect succulents and soil acidity. Some metals, such as copper or zinc, can leach into the soil over time, especially in moist conditions. This leaching can alter the pH of the soil, making it more acidic.
If possible, avoid metal containers and use terracotta or plastic pots (preferably with drainage holes).
If you really want to use that metal container you’ve got your eye on, reduce any potential negative effects by lining it with a plastic barrier or by using it as a decorative outer pot while placing a suitable, well-draining container inside to ensure the soil and succulents remain protected.
How Can I Find The pH Level Of Soil?
If you are serious about providing the absolute optimal growing conditions for your succulents, you’ll want to find the pH level of your plant’s soil.
It is simple to test with a pH test kit. pH test kits are available at most garden centers or online. Alternatively, a simple soil test can be done by your local Cooperative Extension office.
What Are The Signs Of A pH Imbalance In Succulents?
If you notice any of the following signs in your succulents, it could be a sign that their soil pH is out of balance.
Leaf Discoloration: One of the most noticeable signs of pH imbalance is leaf discoloration. If the soil pH is too acidic, you may observe yellowing leaves. On the other hand, if the soil is excessively alkaline, the leaves might develop a bronze or reddish tint.
Stunted Growth: A soil pH that is not suited to the plant can hamper nutrient uptake from the soil and result in slow or limited growth.
Leaf Burn or Scorch: In alkaline soil, the accumulation of salts can lead to leaf burn or scorch, characterized by brown or dried-out leaf tips or edges. In acidic soil, excessive acidity can cause a similar effect.
Reduced Flowering: If your succulent is in a soil with a pH that does not suit it, its nutrient uptake will be reduced and it may produce fewer or no flowers, or the flowers may appear smaller and less vibrant.
General Decline in Health: Succulents subjected to prolonged pH imbalances may show an overall decline in health. This can include wilting, increased susceptibility to diseases and pests, and decreased resilience to environmental stressors.
It’s important to note that while the signs listed above can indicate a pH imbalance, they may also be caused by other factors such as inadequate light, improper watering, or nutrient deficiencies.
Always conduct a soil pH test before trying to adjust the acidity or alkalinity of soil.
Which Succulents Like Acidic Soil And Which Prefer Alkaline Soil?
There are several succulent species that generally prefer slightly acidic soil, while others tend to thrive in slightly alkaline soil. Here are some examples:
Succulents that prefer slightly acidic soil (pH 6.0 to 6.5):
- African Milk Tree (Euphorbia trigona)
- Christmas Cactus (Schlumbergera bridgesii)
- String of Pearls (Senecio rowleyanus)
- Panda Plant (Kalanchoe tomentosa)
- Flaming Katy (Kalanchoe blossfeldiana)
Succulents that prefer slightly alkaline soil (pH 7.0 to 7.5):
- Aloe Vera
It’s important to note that while these succulents generally prefer the mentioned pH ranges, they can still tolerate a wider range of pH levels to some extent. Additionally, individual preferences may vary within each species, so it’s always beneficial to monitor the specific needs of you plant and adjust the soil pH accordingly to create the most favorable growing conditions for them.
How Do I Adjust The pH Level Of Soil
Once you have determined the ideal pH level for your succulents, you will need to make sure that the soil is amended accordingly.
If the pH level is too low (under 6.0, which is too acidic), you can add limestone, dolomite, or crushed eggshells into the soil. These will gradually neutralize the acidity over time.
If the pH level is too high (over 7.5 which is too alkaline), you can add sulfur, pine needles or coffee grounds to lower it.
Be sure to follow the directions on whatever product you use, and always test the pH of your soil before making any adjustments. Whatever adjustments you make, be gentle and do so sparingly.
If you’re not sure how to adjust the pH of your soil, or if you don’t want to mess with it yourself, you can always ask a professional for help.
A local nursery or cooperative extension office should be able to give you some advice, or you can always hire a professional landscaper or gardener to do it for you.
Can Succulents Survive In Any Soil?
The answer is yes, succulents can survive in most soils. They are extremely hardy plants, in general, and tolerant of poor soils.
The most important attributes of soil for succulents are:
- well-draining – succulents don’t like to sit in wet soil, so it’s important to make sure that the water can drain away quickly. If the soil is too dense, the roots will start to rot and the plant will die.
- nutrient level – succulents need very little fertilizer, so if the soil is too rich in nutrients, they may suffer from root burn and start to decline. It’s best to use a light hand when fertilizing succulents.
You can purchase soils specifically for succulents and cacti from local garden centers or online. If you’d like to try your hand at making your own succulent soil-mix, check our article What Is The Best Type Of Soil For Succulents and Cacti In Pots?
Succulents are popular houseplants because they can thrive in a wide variety of environments. Signs of an imbalance in pH can include stunted growth, discolored leaves, and a lack of flowers.
A healthy pH for succulents is between 6 and 7.5 but most commercially available soils created specifically for succulents and cacti should provide the correct pH level for your plants.
Adjusting soil pH is really quite an advanced maintenance level for your succulents and you should only try to alter the pH level of your plant’s soil if you are happy to experiment. Whatever you do, use a very light touch.