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Because we think succulents are naturally tenacious, we’re often surprised by their bad behavior.
Edema, which causes swellings on the petioles and lower leaf surfaces, is the primary cause of succulents turning brown. Corking is caused by excessive soil moisture, insufficient light, or cold. Other causes for browning may include salt buildup, water purity, or a need for repotting.
The basic, simplified answer to your question is that your plant is in distress. That said, fear not; you’re not alone. Succulents, and especially cacti, are known to present with occasional browning.
So, let’s take a look at possible causes and their solutions.
What Could Cause My Succulent To Turn Brown?
The most common causes of succulent browning are:
Cacti are recognized for their resilience and low maintenance needs, and they typically only need well-draining soil, enough sunlight, and water when dry.
Pests are rarely a problem with cacti but may affect other succulents. Although stem dryness and browning are standard, basic care steps can quickly fix the problem.
We all love our plants and want them to share our space as long as possible. When not accompanied by experience, that love can often cause our plants distress – even when our intentions are only the best.
Let’s explore these in some detail, and, most importantly, let’s see what we need to do to fix them.
Poor Root Health
The problem may be root rot if your succulent’s base turns brown and the stem is limp and yellow.
Because root rot develops out of sight, it’s challenging to identify before its development is quite advanced. Root rot symptoms usually won’t appear until the condition has progressed.
When you notice signs of root rot, stop watering the plant and repot in well-draining soil as soon as possible.
You could also try to save your plant by removing any rotting tissue and a small portion of the surrounding good tissue.
To do this, use a new razor or sharp knife disinfected in boiling water or cleaned with alcohol. This is important to do this between each cat to prevent spreading the rot through healthy tissue.
When you’re finished, apply sulfur powder to the wounds to aid the plant’s healing.
All succulents need soils that drain quickly. Several retail nurseries provide specialized “cactus” mixtures, which are designed for plants in pots.
Poorly draining soils will make plants more vulnerable to infections that cause root rot and even kill plants.
Sunburn is the most frequent and likely cause of your succulent’s top becoming brown. It may seem strange because most equate cactus with scorching, arid deserts.
However, certain cactus species do not thrive in direct sunshine; some require medium lighting and some shade to grow well.
Most plants need to be hardened off (acclimatized) to new environments, and new plants need to be transitioned from their nursery environment to brighter conditions.
Tell-tale sunburn often manifests as a pale discoloration on the plant’s sun-facing side. The delayed intervention will cause the plant to develop severe sunburn, drying, and browning of the spot.
Little can be done to undo the damage caused by severe sunburn.
However, if your plant has white patches, you can save it by moving it to a shady location. It will fully recover if you provide shade on the hottest days of the year. Learning about your plant’s lighting requirements will also help you provide the best conditions.
Cactus not indigenous to the region must be progressively acclimatized (hardened off) to full sunlight over many days. Incrementally increase their exposure every three to four days.
Edema, or Corking
A healthy cactus plant may show signs of corking when solid, brown tissue suddenly appears a few inches above the earth.
An edema-related physiological condition causes rough, corky swellings on the lower leaf surfaces and petioles. Plant edema is caused by excessive soil moisture, insufficient illumination, and cold temperatures.
It usually happens in the winter on succulent plants. The plant’s leaves begin to yellow, droop, and fall off if the damage is left untreated.
Edematous leaves won’t return, but you can stop a plant’s decline by increasing light and watering less frequently.
Repotting to enhance soil drainage might also be beneficial. Never let indoor plants stand in a saucer of water.
The spots begin as tiny, black circles that grow larger over time until they have a diameter of one to two inches. The emergence of callus tissue prevents further advancement.
The disease is partially physiological and is primarily impacted by soil moisture. Destroy and remove sick specimens.
Stem Rot of Cacti
Cacti seedlings with basal or top rot develop into a shriveled, spore-covered mummy. Yellow patches are the first symptom; the plant can rot to the core within four days.
Pests that Cause Succulents Distress
A healthy, unstressed plant is more resilient at enduring the occasional insect infestation than plants that faulty management practices have stressed.
Examine plants thoroughly before buying any cacti, agaves, or yuccas to prevent bringing the pests home and infecting your other plants.
Stressed agaves are more vulnerable to soft scale, and stress could be brought on by insufficient water or unfavorable growing circumstances.
The most vulnerable plants have been neglected; thus, they must be checked frequently for pest symptoms. The plant might already be beyond repair by the time the scale is found.
Although they are not insects, mites are related to spiders. Because they are so tiny, mites can only be seen under a microscope or with a magnifying glass.
Eriophyid mites, a plant-feeding mite that frequently induces galling or abnormal growth of the host plant tissue, attack aloes and other species like Haworthia and Gasteria.
Poor Watering Practices
Overwatering is one of the most dangerous abiotic issues, and this, together with soggy soils, is a surefire prescription for plant failure.
Depending on the type and species of the plant, the interval between irrigations should be moderate to thorough.
Contrarily, additional water will lessen heat and sun damage issues during droughts or extended periods without rain.
Watering succulents in well-drained soils every 10 to 14 days should be sufficient to ensure plant health and growth during the summer.
The watering period may be shortened on denser soils, such as clay. The frequency will need to be increased on sandy or very quickly draining soils.
The root zone should be checked two to three inches (5–7.5 cm). Wait to irrigate the soil until it has dried out if the soil is even a little damp.
You may better understand your plants’ water requirements by inspecting the root zone before watering.
After thorough irrigation, there should be a 2–14 day dry interval to allow the soil to dry out and prevent soil-borne diseases’ growth.
In the fall and winter, irrigation may be scaled back as daylight hours get shorter. Irrigation should not be continued when the evening temperature is below 60°F (16°C).
This article summarizes some of the risks to your succulents’ survival. Well-cared-for indoor succulents are resilient to diseases and pests, so keeping them strong should be your first line of defense.