Cactus Scab Treatment: Learn About Scab Diseases Of Cactus

Cactus Scab Treatment: Learn About Scab Diseases Of Cactus

Gardeners must be ever vigilant when it comes to diseases on their plants. What is cactus scab? Read on to learn more.

What is Cactus Scab?

Cactus scab is particularly common on prickly pear cactus but can affect many other varieties. It is a form of edema, where something has stimulated an abnormal increase in the size of the cells. This results in strange patches on the skin of the plant. It occurs in many other plants too, such as:

  • Tomatoes
  • Cucumbers
  • Potatoes
  • Begonia
  • Violets
  • Cabbage

Cracks, discoloration, dry scabby lesions? Identifying the issue is quite easy, although the appearance can be mistaken for sunscald or spider mite attacks. Initial signs of scab of cactus are pale yellow spots on the skin of the plant. These become irregular, corky or rusty. Hence, the name corky scab. The whole effect looks like the cactus has a patch of eczema. Essentially, the cells in the epidermis are breaking and opening up, resulting in almost wound-like lesions.

The oldest parts of the plant are usually the first to show signs, with young shoots rarely being affected until they mature. Some plants experience just a few patches, while others can become covered in them.

What Causes Corky Scab on Cactus?

It is believed to be caused by poor cultivation methods and, once noted, can be halted before it damages any more of the plant. Corky scab on cactus is primarily an aesthetic disease, but it can have economic impact in commercial growing. Luckily, the problem is easy to prevent by changing cultural methods.

As one of the more common diseases of cactus, corky scab is thought to be the result of overwatering, low temperatures and poor ventilation. It is most common in areas where there is abundant, warm water in soil and cool, moist temperatures. Other situations thought to stimulate the disease are high light, injury to the plant, chemicals and poor drainage.

Since most of these conditions can be controlled, cactus scab treatment relies upon changing the cultural situation and methods. Outdoor plants may need to be moved to a location where more control over wind, temperature and ambient humidity are possible.

Cactus Scab Treatment

There are no sprays, drenches or systemic preparations for cactus scab treatment. Avoid irrigating in cool, moist weather and ensure good drainage is occurring. Never let a cactus sit on a saucer in water.

If plants are indoors or in a greenhouse, increase ventilation. Increase the temperature of the area in which the plant is being grown. Avoid fertilizing in fall and winter, and do not use a formula with a high nitrogen content. Keep light bright but not above 14,000 foot candles, or lumens. If necessary, repot the plant into fresh cactus mixture.

Generally, going back to good cactus cultivation and ensuring good light, watering practices and diminishing humidity will prevent any further corking and see your plant back on the road to optimum health.

Cactus and Succulents forum→Jade plant problems

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Any advice on any aspects would be greatly appreciated! I'm a new jade owner and I want it to be healthy!

Overall I think your plant looks very healthy. Jades do lose leaves fairly regularly (at least mine does, and it's at least 15 years old). I don't know what the little specks are -- but it may be getting kind of "fried" in the west window exposure the afternoon sun from the west is pretty intense. Perhaps @Tarev can give you more of an expert opinion, though (TIA, Tarev)

Does the new pot have a drain hole in the bottom?

@purpleinopp it does have a drain hole at the bottom, I also added a layer of rocks and there is a plastic tray with holes too! Lots of drainage.

You did mention you have repotted the plant in May, so it is also acclimating again in its new growing condition. Are you able to bring your plant outdoors? It will love good airflow around it, if you can put it in part sun/part shade area to acclimate slowly. Now even if the plant may seem to be a bit slow growing in summer, it still appreciates a good through watering, it still drinks water, it is in summer that I do see it fatten up its stem.

Glazed containers are quite pretty, I also have mine in one, but it does hold water far longer at the root zone, so make sure you check the media has dried out a bit, putting a rock at the base of the plant helps. If it shows damp when you lift the rock, then your media is still wet and delay further watering just a bit more. This plant is quite efficient storing water in its leaves and stem, so you have to allow a good interval in watering.

Few jade owners report scab problems. It mustn't be a common malady. Thus far, I have not found a gardening site or forum to actually identify the "disease," and/or offer a knowledgeable treatment. If you know something that the rest of us don't, please, please clue us in. Many thanks. Dennis.

Dennis, can you add a photo of your 'scabs'? I don't see the scabs on terbear's plant either. Jade plants do have larger than normal pores on the leaf surfaces. Is that what you are looking at?

Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming. "WOW What a Ride!!" -Mark Frost

President: Orchid Society of Northern Nevada

It often occurs when one's growing area maybe too humid, or simply overwatering the plant. Giving good watering intervals helps, as with good airflow all over the plant.

Indoor growing environment limits good light and air flow around the plant as well as good gas exchange that occurs at night for the jade plants. Though the plant will still grow, it is not as robust as when it is grown outdoors in its preferred light intensity and temperature needs. That is why I often advise for indoor growers, makes sure media is porous and open, use containers with drain holes, position plant to as much light as you can indoors and do watering intervals.

You have to give us more information:
1) is it grown indoors or outdoors
2) what is your watering regimen
3) in what part of the world are you growing your jade plant
4) what medium did you use when you planted it
5) is it an old plant or newly acquired
6) did you recently repot the plant
7) post a photo of the plant
8) what type of container are you using and does it have drain holes

If it were mine, I won't mix in another succulent. Jades can easily fill the container as it gets older and bushier, so the other succulent might suffer from poor light access.

It is a matter of preference too, they do have similar growing needs.

If it were mine, I won't mix in another succulent. Jades can easily fill the container as it gets older and bushier, so the other succulent might suffer from poor light access.

It is a matter of preference too, they do have similar growing needs.

I have to agree jades can grow quickly . Here are two pics of a jade I bought recently. The first on the day I got it in mid feb and another from today . Amazed at how fast it is growing

Hoping someone can help. Both these 2 jade plants at plant shop about 4 weeks ago. They are in a west facing window and get direct sun in late afternoon. I water every 2 weeks. The soil is very dry at that 2 week intervals. Plants are in a 2.5 inch pot. Live in Canada . 2 leaves seems to have been torn on the same plant. Nothing so far for 2 nd plant . see pics . I don't recall those tears being there when I bought them. Can anyone help? Thanks

Choosing the right soil

I recommend this wonderful cacti soil mix by repotme. The quality is better than anything else I found on the market, and should help you grow a healthy cactus.

    High Quality Mix, Handcrafted in small batches Blended With Monterey Pine Bark from New Zealand, Red Volcanic Rock, Diatomite, and Premium Grade Pumice.

If you leave your prickly pear with too much water for too long, it can get root rot.

On the other hand, if the water drains too fast, your cactus will not have enough time to absorb the nutrients it needs to grow.

The good news is that you have a lot of leeways when it comes to choosing the right soil for your prickly pear because it’s hardy enough to grow in not-so-perfect soil.

Prickly pear, however, will grow better and easier in sandy, loamy, and well-draining soil.

Tips and Tricks

If you have heavy soil that retains water, you can add sand or peat moss to amend it.

This will make heavy soil like clay or compacted soil drain better.

Further, if you are growing prickly pears in containers, you can add a layer of gravel at the bottom to help with draining the water.

1. Overwatering

Typically, cacti plants don’t thrive in wet and poorly drained soil. Poorly drained soils cause water to fill up air spaces between soil particles, which prevent the much-needed root aeration. The damp conditions also provide favorable conditions for fungi and harmful bacteria to multiply.

As a result, the roots of your plant start to die, and disease-causing organisms get an opportunity to move into the stem tissue causing soft spots to start developing in different parts of the stem.

If you suspect that the problem is overwatering, then you need to stop being overzealous when watering your plant. Always wait until the top two inches of the soil are dry completely before you water again. Other than creating a watering schedule, let the potting mix tell you when you need to water your succulent.

For cactus growing in the ground, it takes much longer for the soil to dry out completely after watering. Consider using a probe to check the soil moisture before you water, again. Avoid watering your cactus if it rains.

Fungal Leaf Spot

Epiphyllums occasionally experience a common fungal disease that is known as fungal leaf spot. Fungal leaf spot is especially frequent with epiphyllums during periods of cooler temperatures in the wintertime. Some signs of the disease include the yellowing of the foliage, followed by the foliage turning brown. Plant drop is another sign. The disease spreads particularly rapidly and easily with wet leaves. The disease can be avoided by abstaining from wetting leaves, and watering the plant in the early hours of the morning to allow the leaves to quickly dry. It is also vital to avoid pruning plants that are wet.

  • Epiphyllum is the name of a genus that is part of the Cactaceae (Cactus) plants.
  • Epiphyllums occasionally experience a common fungal disease that is known as fungal leaf spot.