I recently purchased a large cast iron plant online when I found it on sale for a great price. I had been wanting one for a while as they are pet-friendly and can tolerate lower light levels, so this was the perfect opportunity to get one. Unfortunately, the timing of getting this new plant wasn’t ideal as it arrived about a week before we were leaving to go on holidays.
Before we left on holidays, I had noticed a small area of webbing on one of the leaves, but just thought this must have been something that happened during shipping and probably wasn’t anything to worry about. I had never had spider mites on any plants before and didn’t know much about them.
When we returned from holidays, the plant wasn’t looking all that great, and continued to get worse. I thought that maybe it had been over-watered. Finally, I inspected it more closely and realized that the damage was worse than I thought! I found more webbing and all of the other signs of spider mite damage, such as stippled leaves and a yellowish residue when you wipe the leaves with a cloth. The leaves looked very dirty (almost like dust) even though I had cleaned them a couple of times already. I knew then that it was definitely infested with spider mites, and I was so sad that this large, expensive plant may not survive. Spider mites are notoriously hard to deal with!
But with it being a large, expensive plant, I decided I would try my absolute best to clean it up and see if it would survive! And I am so glad I did because now, months later, there are no signs of spider mites and it’s looking much better, even though I had to remove several leaves and many brown tips.
Here’s exactly what I did to save this plant:
1. Remove any severely damaged leaves (cut off at the very bottom of the stem near the soil line), and trim off any brown tips on leaves (trim the brown tips off at an angle to mimic the natural point of a leaf). Wipe down all the leaves with a damp cloth as best as you can.
2. THOROUGHLY spray down all of the leaves with a water sprayer using room-temperature water. The goal here is to remove/displace as many spider mites as you can. Be sure to spray both sides of the leaves. To do this, I placed my plant in our tub and used a portable water sprayer. I was also still concerned that my plant may have been overwatered, so I tilted my plant to the side when spraying the leaves to try and prevent the soil from getting too wet (this may not be necessary for you if your plant needs water). I also didn’t want the spider mites to end up in the plant’s soil.
- This is the water sprayer that I used (above), and I am SO glad I had it. I loved that it gave me control of where to spray, which made it easier to spray both sides of the leaves. I’ve used this sprayer for a variety of cleaning tasks around the house & patio and highly recommend it!
- You can also use a handheld attachment on your showerhead to do this, or if nothing else, simply give it a shower with your shower head, splash it with water from your tub spout, or pour water on it from a cup (whatever you can do to wash the leaves!).
3. Next, spray the leaves with rosemary essential oil diluted with water to kill any remaining spider mites. Combine 20 drops of rosemary oil + 1 cup of filtered water in an amber glass spray bottle. Yes, the rosemary oil can actually KILL the spider mites, and it also repels them! This solution of diluted rosemary oil is effective and gentle, and should be applied about 3 times on different days for the best results (spray the leaves one time per day for three days in a row).
In addition, diluted rosemary oil can also be applied once every couple of weeks as a pro-active step to prevent future mite infestations! This is a great thing to do for plants with large leaves like the cast iron, as spider mites are attracted to these types of plants.
4. Lastly, keep your infected plant away from your other plants until it’s clear that the spider mites are gone! You don’t want them to spread to your other plants.
It’s now been a few months since I did the steps described above, and there are no more signs of spider mites! My plant still has some stippled leaves (leaves where the green pigment looks stippled/speckled where the spider mites previously sucked out the chlorophyll), but this is only noticeable if you look up close. I have sprayed it a couple of times in the past few months with the rosemary oil solution, and I plant to continue doing that every once in awhile as a precautionary measure!