Why is My Crown of Thorns Plant Losing Leaves

The Crown of Thorns is my favorite low-maintenance indoor flowering plant. While the flowers aren't huge or overly ornate, I think they are very cute. They add a nice pop of color. And personally, my Crown of Thorns seems to bloom all year round, so you really can't beat that. When you have a beautiful blooming plant like the Crown of Thorns it can be even more concerning when it starts losing leaves. Read on if you want to know why your Crown of Thorns plant losing leaves.

Reasons for Crown of Thorns Plant Losing Leaves

Watering Issues

Watering issues for Crown of Thorns can present in several ways. The leaves may begin to turn yellow or brown. Its a succulent so unlike many other leafy plants the leaves on a Crown of Thorns don't droop like other plants when they need water. Take note of the leaf loss, it it happening all over the plant to a bunch o leaves or just a few? Unfortuneately both over or underwatering can cause leaf drop.

Overwatering

An overwatered overwatered Crown of Thorns can be the cause of leaf loss. Generally the leaves will begin yellowing, then turn brown, crisp up, and then fall. How do you tell if you have overwatered your Crown of Thorns though? You can stick your finger in the soil to see if it feels wet. As a succulent, it does not require very moist soil, so if it feels moist to the touch you might be overwatering. Overwatering can be caused by watering too much, too frequently, or by the pot not having adequate drainage or no drainage. If you suspect that you have been overwatering your Crown of Thorns the you can carefully lift your plant out of its pot to examine the soil and roots. This is how you will really assess the damage of an overwatered plant. If the roots are dark and squishy, then you may have root rot. If that's the case, then you will need to root prune, repot, and hope for the best. I have a whole post on salvaging an overwatered plant.

Underwatering

An underwatered Crown of Thorns displays similar symptoms to overwatering with the progression from yellow to brown to crisp to falling off. Not very helpful I know. It can be hard to tell if your Crown of Thorns is underwatered because ideally you let the soil dry out before you water it again. So if you stick your finger in the soil and it's dry, you might not know there's a problem. If you want to be more precise use a soil moisture meter. One thing to look out for is if the water runs through your pot really fast and out the bottom when you water. If that's the case you soil may have become hydrophobic, meaning it repels rather than absorbs water. If this is happening you can try watering from the bottom, which just means sticking your plant pot into a container of water and allowing the soil and roots to soak it up. In general, its good to check the soil moisture before you water this will help prevent you from overwatering, but will also give you a better idea of how quickly your plant is drying out to prevent underwatering as well.

Fertilization Issues

Fertilizing issues can also cause Crown of Thorns leaf drop. If you have fertilizer issues, some visible signs you might see from your Crown of Thorns will be yellowing leaves or even deformed leaves. Crown of Thorns plants aren't particularly heavy feeders, so it can be easy to overfeed if you're treating it like other hoseplants. Both over-fertilizing and under-fertilizing can cause issues.

Most plant fertilizers contain different ratios of the macro-nutrients n-p-k, nitrogen, phosphorus, and potassium. Nitorgen is the nutrient that primarily promotes leaf growth. Phosphorus promotes root development and budding/fruiting and potassium is for overall health. If you're experiencing leaf drop it may be that you are deficient or too abundant in nitrogen. Depending on your issue and the severity you may need different ratios of fertilizer to fix the issue. They make high nitrogen fertilizers, low nitrogen fertilizers, and balanced fertilizers.

It's difficult to tell whether you have been over or under-fertilizing. You can go based on whether you have been following the fertilizer instructions completely. There should be very specific instructions on dilution, dosage, and frequency of fertilization. Although, as I mentioned earlier if you're following the frequency of feeding on the packaging, you could be feeding too often because Crown of Thorns don't need much. The only real way to know is to test your soil though. These soil rapitests are convenient for that. They are relatively cheap and will give you precise measures of your soil nutrients.

Pest Issues

Pest issues may also be the cause of your Crown of Thorns plant losing leaves. Damage from pests will show up as leaf discoloration, typically yellowing, but it will be more speckled. Generally speaking, pests feed on plant matter so you might notice small spreads of yellow dots. If pests are feeding on your Crown of Thorns you might also see deformed leaves or even small holes in leaves. If you see actual bugs or tiny webs, you definitely have a pest problem.

A number of pests can attack your indoor Crown of Thorns. The most common are pests like aphids, spider mites, scale, and mealybugs. Look under your leaves for aphids, scale, and mealybugs. Spider mites make small webs and often collect around the petiole, leaf tip, and underside of the leaves. I have personally dealt with spider mites on one of my Crown of Thorns in my green house. At leat in my case they were concentrated on the fresh new leaves and there were little webs all over the tips of the plant.

If you suspect you have pests, you should quarantine your plant away from other plants as soon as possible. Pests are too good at spreading to all your plants. Next, do your best to remove the pests you can see. For aphids and spider mites, you can try spraying your plant off with a hose outside or in the shower. Scale and mealybugs have wxy outer shells and have to be removed manually. Many people use alcohol on a cotton swab to do so. Next, treat your plant with some kind of pest control. Organic solutions like neem oil work as well as non-organics like insecticidal soaps. The final tip is to follow the instructions on the insecticide. It may seem like overkill, but it's important to treat your plant for weeks sometimes because of the lifecycle of these types of pests can mean they will pop right back up once you think they're gone.

Is your Crown of Thorns plant losing leaves? If you have more questions post them in the Comments section.