Cast Iron Plants bring lovely color and texture to your home and require surprisingly little care. Many novice gardeners find them the perfect plant because they thrive under various conditions. Having an overgrown Cast Iron Plant is a good opportunity to divide it into smaller plants you can gift to fellow plant lovers!
You can divide a Cast Iron Plant during the growing season by disentangling root systems gently by hand. This method is preferred to cutting although cutting is sometimes unavoidable. You can dip the cut ends in a rooting hormone to encourage root growth after transplant and avoid transplant shock.
If you’re interested in learning how to effectively divide a Cast Iron Plant, setting all plants up for success, you’re in the right place. I’ll discuss methods to divide the plant and tools to have on hand. I’ll also share some tips and tricks to give the new plants the best possible chance of thriving once divided and repotted.
1. Check the Condition of the Mother Plant
The first consideration before you begin the task of dividing your Cast Iron Plant is the condition of the mother plant. This consideration is a bit of a double-edged sword.
Ideally, you are in a position where you are dividing a healthy, thriving plant. If you separate a Cast Iron Plant either because it has outgrown its pot or because you want to propagate other plants, it’s optimal to do so when the plant is healthy and without stress.
This is because the act of dividing any plant creates stress on the plant. Even the most delicate job of separating a plant and its root system still causes stress on the plant simply because you’re removing it from its soil and environment at any time.
Choosing to divide the plant when it is thriving and at its best health is the best tactic. This gives the plant the best chance of success once it has been repotted.
Consider this flipside, however. There can be times when you are dividing a Cast Iron Plant as an act of last resort. You are dividing the plant as a means to save it because it shows signs of stress or injury.
In this case, there’s no waiting for the plant to be at optimal health because by not dividing it, you’re creating a worsening health condition for the plant. Repotting or separating it, even when it’s under stress, truly is the best or only option to save the plant.
In this scenario, there is no sense in waiting for a time when the plant is healthier or when you’re at the optimal time of year. Time is of the essence, and you just need to divide the plant, following the steps outlined below, hoping the plant can recover and reestablish itself under better conditions.
2. Schedule the Division in Spring
It’s also essential to consider the time of year. Typically, plants are in the best position health-wise to be repotted or divided during their growing season. This is because the plant is naturally putting effort into new growth at that time.
In particular, Cast Iron Plants grow actively in spring, and the best time to divide them is between March and April. This will give them enough time and suitable environmental conditions to bounce back.
During the off-season, the plant enters a period of dormancy. This is due to the following reasons:
- days are shorter
- temperatures are cooler
- the air is a bit drier
- light is lower
During this time, the plant typically won’t produce any new growth but instead is conserving energy for the upcoming growing season.
When you force the plant out of dormancy by dividing or repotting it, it causes the plant to put energy into survival during a time of year when it is expending very little energy. This can stress the plant and cause damage that may not be immediately seen but can affect the overall health and survival of the plant.
Instead, the point is to allow the plant to grow, thrive, and propagate as needed. If it’s possible to avoid putting the plant under additional stress, that’s always the preferred alternative.
3. Prepare the Necessary Tools
Once you have weighed your best options with respect to the time of year and condition of the plant, there are a few items to have on hand in order to divide a Cast Iron Plant.
Necessary Tools To Have on Hand
If you already have a Cast Iron Plant, chances are good that you already have some of these items on hand and should not need to purchase anything new.
New Plant Pot(s)
If you’re going to divide your Cast Iron Plant, in addition to the existing pot that houses the plant, you’ll need a new pot or pots to plant the divided plants. Since it is a Cast Iron Plant, logic might tell you that any pot will do, but unfortunately, it’s not that simple.
Cast Iron Plants can tolerate various conditions but prefer to be in a rather snug plant pot. Some plants like to be rootbound or in a planter where they can scarcely grow another millimeter of roots. This isn’t the case for Cast Iron Plants.
While they prefer to be in a smaller pot for the plant size, they do need some room to grow and expand. When dividing a plant, it’s recommended that you split it into two equal parts and place one back in the original pot and another in an equivalent-sized pot.
If you want to split them into two new pots, be sure to purchase pots that are the same or very similar in height and circumference to the original pot. Placing the divided plants in oversized pots will not encourage new growth. Instead, this discourages new growth in Cast Iron Plants.
It’s also essential to choose plants that drain freely. Cast Iron Plants prefer to dry out completely in between waterings and don’t particularly appreciate having “wet feet” or damp soil around their root system.
Pots draining into a catch tray are ideal since you capture the excess water and can pour it down. I don’t recommend letting the pot sit in drained water as this could lead to damp roots and, ultimately, root rot.
Planter pots without drainage holes at the bottom can be beautiful, highly decorative, and attractive to new plant parents because you don’t have to worry about water accumulating on surfaces. However, these pots are not best for Cast Iron Plants because they don’t drain water away from the plant.
If you must use a solid-bottomed pot, don’t plant your Cast Iron Plant directly in the pot because this promotes wet soil and roots. Instead, plant your Cast Iron Plant in a slightly smaller plastic pot that can be placed inside the solid-bottomed pot.
During the scheduled watering session, you can take out the plastic pot and water it in the sink. Doing this allows the water to drain freely through the bottom of the plastic pot. Once the water stops dripping from the bottom of the container, you can place it back inside the larger pot.
Another item that you must have on hand is potting medium. Just like with planter pots, choosing a potting medium that meets the plants’ needs is crucial. Cast Iron Plants like a thorough watering but prefer to completely dry out in between waterings.
Typical potting soil with vermiculite is designed to retain as much moisture in the potting medium as possible, making it less ideal for Cast Iron Plants than other alternatives.
Instead, select a potting medium that promotes fast drainage. You can amend the potting medium by introducing some landscape sand or sphagnum peat moss and stirring it into the potting soil to distribute it evenly.
Although the sphagnum peat moss holds a large amount of moisture, its porous nature allows air to easily circulate and dry out the potting medium more quickly. That way, your plant won’t sit in excess moisture for too long.
As an alternative, cactus or succulent soil works great for Cast Iron Plants. African Violet potting mix is another good alternative if sand or peat moss isn’t available in your area. Either of these mixes promotes fast drainage.
4. Dig Out the Plant When Half the Soil is Dry
Once you are in the right time of year or at the right time to divide your Cast Iron Plant, and you have all the tools you need for the task, it’s time to start dividing plants!
The best time to dig out the plant is when the soil is almost dry. I recommend checking the soil 2-3 days before your next watering session. If half the soil is dry, then your plant is ready for division. The plant should be reasonably dry so that it’ll be ready for thorough watering after division and replanting.
If the soil is dry enough, you can follow the steps below:
- Tip the plant upside down, using the palm of your hand to catch as much soil as possible and support the plant.
- Avoid pulling the plant out by the stems, as you can break the plant or the roots.
- Remove as much soil from the plant roots as possible.
5. Inspect the Plant for Suitable Sections for Division
Once you have the plant out of the pot, inspect the plant for a natural break between individual plants. You’re looking for places where the plant could easily be separated. Using your thumbs and fingers, begin to gently disentangle the plants and their corresponding roots.
I try to peel them away from one another, similar to peeling an orange by hand. Slowly and gently, taking care not to tear or break roots, peel the plants apart until you have two different plants. It’s okay if soil and potting matter breaks loose and falls out of the roots.
Occasionally, you will find a plant that is so rootbound that separating the roots gently simply isn’t possible. In this situation, I use a thin paring knife to gently separate roots that have grown together.
6. Dip the Roots in A Rooting Compound
Cast Iron Plants grow very slowly. That’s why growing new ones from cuttings or divisions is the best way to propagate them. And although these plants are relatively easy to care for, they’ll need some boost before replanting, especially when cut.
Using rooting hormones can help them overcome transplant shock and encourage them to grow new and healthy roots.
7. Repot Your Cast Iron Plant in Fresh Potting Medium
Cast Iron Plants can tolerate various types of soil but do best in well-drained soils. So if you’re using loose soil, place a coffee filter or mesh at the bottom of the pot to prevent the soil from leaking out every time you water your plant.
Fill a third of the pot with fresh potting mix. Gently spread the plant roots on the substrate and loosely cover the plant with the remaining potting matter. The soil should reach up to a ½ to 1 inch (1.27-2.54 cm) below the lip of the pot.
Water the plant deeply until the excess water drains out of the holes at the bottom of the pot. When half the soil is dry, you must water the plant again. After a month, you can revert to your regular watering routine.
8. Apply Organic Fertilizer
Cast Iron Plants may be slow-growers, but they do appreciate nutrient-rich soil. If your potting mix lacks essential nutrients, you can supplement the missing nutrients with organic fertilizer.
It helps to have a balanced organic fertilizer on hand for regular feedings. This can be a helpful tool to use once you have repotted the divided plants. You can dilute it in water and use the solution to water your newly repotted plants for the first time.
Using a light mix of organic fertilizer, water the newly potted plants thoroughly, making sure to soak all of the new soil in the pot. Water the plant until water flows freely from the bottom drains.
Why Divide a Cast Iron Plant In the First Place?
People love the Cast Iron Plant for many reasons. It is a lovely shade of green and adds beautiful texture to a collection of houseplants. Most people get this plant because it is very hardy and low-maintenance.
If this describes you, you may be wondering why you would even need to divide a Cast Iron Plant. There are a few reasons you may find yourself in a position of wanting or needing to divide up your Cast Iron Plant. Here are the two most common causes.
The Plant Has Stopped Growing
Cast Iron Plants are generally a slow-growing species compared to many other houseplants. Even having said that, there may come a time when it appears that your Cast Iron Plant has stopped growing or generating new growth completely.
Several reasons may cause your plant to stop growing, and one of them is when the plant has outgrown its pot. In this case, dividing or repotting the plant is often the only thing that will get the plant to grow again. In fact, if you take no action, the plant will die eventually.
If you’re unsure why your Cast Iron Plant isn’t generating new leaves, I have an excellent resource for you. For a complete explanation as to why your plant won’t produce new leaves, check out this in-depth article: How to Help a Cast Iron Plant That Won’t Grow New Leaves
You Want More Plants
The other main reason people need to divide a Cast Iron Plant is that they want more plants. Perhaps you are hoping to add another lovely plant to your space. It’s also possible that someone saw your plant and would like a Cast Iron Plant of their own.
Yet others decide that they would like to have a few smaller Cast Iron Plants on hand for various reasons. A young, healthy plant in a pretty pot makes a lovely housewarming gift for a new neighbor, a perfect hostess gift for a friend that invites you over for a cookout, or a present for that one person for whom it is impossible to find the right gift.
In any of these scenarios, you can certainly run to the store and pick a plant out, but it’s such a personal gift for someone when you have propagated the plant yourself. You can select the pot and put the time and energy into making the plant happy and healthy.
Since it’s a Cast Iron Plant, you can give it to experienced plant parents and houseplant newbies alike with confidence that they can successfully keep the plant alive. For extra assurance, you can print up some information about the species and some general care instructions for the recipient.
Dividing a Cast Iron Plant is a relatively simple task to complete. It requires some forethought, planning, and gathering the correct tools before separating the plant. But once you have everything you need and the timing is correct, the actual plant division is a simple task.
Don’t let it intimidate you the first time. Go slow, be gentle, and take as much time as you need to not put the plant under additional stress. In short order, you will find the task of dividing your Cast Iron Plants to be a fun and rewarding task.