The cast iron plant, native to Taiwan and Japan, gets its name from its seemingly indestructible nature. This plant is perfect for beginner plant owners or those who want to beautify their space with a plant but do not have the patience or skills to care for a needy plant.
In this article, we will discuss the proper cultural care of the cast iron plant, as well as how to correctly propagate it. So, if you are considering adding a cast iron plant to your collection, keep reading.
Cast iron plant care
Cast iron plants prefer bright, indirect light. Do not place them under direct sunlight, because this can burn their leaves. This plant is able to tolerate low light conditions, which makes it a perfect office plant. The fluorescent lighting inside office buildings is quite enough to keep the plant alive.
If you are keeping the plant indoors, place it near a north- or east-facing window. If the only available window lets in harsh light, you can diffuse the intensity of the light by placing a sheer curtain over the window.
There is no set schedule for a plant owner to follow when watering this plant. The frequency of watering will depend on the climate where you live, the season of the year and the current weather conditions. In winter, in a place with a cold climate and lots of rainfall, you will not need to water the plant as much as someone who lives in a warm, dry climate, in the summer, with little to no rainfall.
The best way to know when to water the plant is by touching the top two inches of soil in the pot. If the soil is dry, you can water the plant, but if it is still damp, wait one or two days before checking the soil again.
These plants can tolerate a certain level of drought, but try not to let your plant go without water for extended periods of time. Watering it on time will always be best for it.
The worst watering mistake a plant owner can make is overwatering a plant. When the plant is overwatered, its roots will be suffocated and will drown. These dead roots will start to rot and become susceptible to opportunistic pathogens. The pathogens will exacerbate the spread of the rot to the rest of the plant and, before you know it, the stems and leaves will be soft and mushy from excess water and rot.
If you suspect that your plant is overwatered, remove it from its pot and wash off as much of the old soil as you can without damaging the roots. Inspect the roots closely, and if you see any black or brown roots, cut them off using sterilized scissors. Make sure you remove all the rotten roots, leaving only healthy white roots behind. Spray the healthy roots with a fungicide to protect them, and let them air-dry for a few hours. When the roots are completely dry, repot the plant in a new pot that has drainage holes at the bottom, using fresh, well-draining soil. Try to be more vigilant about watering in the future, because overwatering can mean life or death for your plant.
The cast iron plant does not need humid conditions, so there is no need to take any extra measures to increase the humidity around it. It does well in dry and even drafty living conditions and will be fine in areas of the house where warm or cold drafts flow through. Nevertheless, it is still best to not expose the plant unnecessarily to any drafts that may sap its moisture faster than normal.
This plant is very hardy and can be kept outside the house for most of the year, but keep in mind that winter frost may be the one thing that can truly kill this plant. It is best to move it indoors at the start of winter to keep it happy.
The room temperature inside the house is good enough for the plant; unlike for certain other plants, there are no specific temperature preferences to cater to. As long as the temperatures are not in the extremes for any reason, the plant will do just fine.
This plant is not particular when it comes to the kind of potting mix you use. Any well-draining, commercially-available indoor plant mix will do just fine. If your potting mix is not very well-draining, you can always add some perlite to the mix. Perlite is a material that makes the potting mix more airy, porous, and well-draining, reducing the chance of overwatering and therefore also root rot.
The pot you use for the plant should have drainage holes at the bottom so that any excess water in the soil will simply flow out. Avoid using plastic or steel pots because these materials do not allow water and air to pass through them as easily as clay or terracotta pots.
If you want to support your cast iron plant by feeding it, give it liquid indoor plant fertilizer once a month during the spring and summer, which is the plant’s growing period.
These plants are typically slow growers, so fertilizer is not a necessity.
Avoid fertilizing during the fall and winter because this can lead to soil toxicity which will do the plant more harm than good.
Repotting the plant
The cast iron plant grows slowly and can tolerate being slightly rootbound, so repotting is not urgent and does not need to be done that frequently. It is normally done every two to three years, or when the plant gets too big for the pot; that is, if the plant is literally breaking the pot or the roots are starting to grow out of the pot’s drainage holes.
When choosing a new pot, only go one size up; do not go too big for the plant. A bigger pot means more potting mix is used. More potting mix means more water will be retained, and more water increases the chances of overwatering the plant.
Repot the plant during the growing period in spring and summer. Repotting is a traumatic experience for the plant, so it will need to be actively growing in order for recovery to be swift.
Pruning the plant
Being a slow grower, the cast iron plant does not need much pruning. If there are dead or dying leaves near the base of the plant, you can remove them gently to preserve the plant’s aesthetic.
Outdoor cast iron plants are sometimes pruned if they get bigger than their owners like, but that is not often needed for plants grown indoors, because they do not get so big anyway.
If you do wish to prune your cast iron plant, make sure you use sterilized pruning tools so that you do not spread any disease.
Do your pruning during the plant’s growing period so that it can recover properly from the trauma of pruning.
Cast iron plant propagation
Propagate your cast iron plant through division. This means you are going to be taking small parts from the parent plant which will grow into their own individual plants.
You can remove the sections by uprooting the parent plant and pulling off pieces that have their own root system. Sometimes each piece you remove has multiple stems on it, which is even better. Separate it from the parent plant as gently as you can so that the roots do not break. If you need to use scissors to sever the tangled roots, do so, but only as a last resort. It is important that the roots be kept intact as much as possible.
When a section has been separated from the parent plant, place it in a pot with a well-draining potting mix. Water the potting mix, but do not overwater it. You can now care for the plant as you would a regular plant.
It is best to propagate these plants during the spring and summer.
The cast iron plant is one of the hardiest, low-maintenance houseplants in the world. It is a great choice as a gift for a beginner plant owner because it is quite impossible to kill. It can tolerate drought and extreme weather conditions for a certain time and does not need to be pruned.
The plant only needs to be watered if the top two inches of potting mix are dry. It likes bright, indirect light and is completely fine with room temperature and normal humidity. It is a slow grower that does not need frequent repotting, and fertilizing is optional.
You can propagate this plant by division. This is when you separate pieces of the parent plant that have their own root system and plant them in their own pots. It is very easy to do, which is why propagating the cast iron plant is such a breeze.
Image: istockphoto.com / skymoon13