The Best Way to Propagate Spider Plants

If you follow my Instagram, you know that I own a *lot* of plants. A few weeks ago, I was handed down my grandmother’s spider plant. I’m not one to say no to a free plant- besides, how hard could it be?

What is a Spider Plant?

Spider plants (Chlorophytum comosum) are a common houseplant which are allegedly easy to care for (I just got one, so I don’t have much firsthand experience to back that up). These plants are native to tropical and southern Africa, and tend to do best indoors with bright, indirect light.

This is the spider plant I received from my grandma. It actually consisted of several plants together in a single large pot. You can see tendrils extending from the plant with a handful of young “plantlets”

What makes spider plants unique is their reproductive strategy- they produce long tendrils which produce small plantlets, which are basically tiny plants with their own roots and leaves. What makes spider plants fun is that these plantlets are easy to remove and grow into new plants, aka propagating. (Disclaimer: it helps if you wait until the plantlets have begun developing roots).

When I received my spider plant, it had A LOT of plantlets. I removed 33 which had already begun to develop root nodes. Since I had so many (and had never attempted propagating this plant before) my husband and I thought it would be fun to try three different propagating methods: damp paper towels, water propagation, and soil propagation.

The Experiment & Methods

On November 23, 2020, I removed 33 plantlets from the mother plant, dividing them equally into three groups of 11 (each with a variety of plantlet sizes). These groups were then assigned to one of three propagating treatments:

  • Damp paper towels: I placed 11 plantlets into two bowls lined with paper towels. I heavily misted the plants/towels with distilled water until the towels were thoroughly damp. I repeated this at least every morning.
  • Water propagation: I divided the 11 plantlets among 4 small glass containers, which were filled with tap water until the roots were submerged. If water levels got low, I would add more until the roots were submerged again (once or twice a week).
    • Tip: For containers, I use a variety of glass containers that I’ve acquired over time. I find shot glasses to work especially well for propagating.
  • Soil propagation: I divided the 11 plantlets into two 3.5 inch nursery pots containing soil medium (Miracle Gro potting soil). I ensured that the roots were below the soil surface, and lightly packed the soil down. At the initial planting, I watered thoroughly with tap water until water drained out the bottom. In the following days, I would periodically spray the soil every couple of days (the goal was to keep the soil damp, but not saturated).

All 33 plantelets were placed in a northeast-facing window, which recieves bright, indirect light for 8-9 hours a day.

The experimental setup. The “Paper Towel” group is in the white bowls on the left, the “water propagating” group is in 4 glass containers at the top of the image, and the “soil propagating” group is in the two pots in the bottom right of the image.

The Verdict

The Loser

Propagating the plantlets on damp paper towels did. not. work. for. me. As of December 1st, there was no visible root growth and the leaves were beginning to wilt. At that point, I decided to terminate that treatment and shifted the plants to water (where they quickly recovered and began growing roots). I *might* have been more successful if I had attempted to create a small greenhouse using plastic wrap- but since there were other clearly effective methods, I didn’t feel like it made a lot of sense trying to make it work.

Aside from the fact this method did *not* work for me, there were some clear cons- the most obvious being that I had to water these every. single. day. Possibly more than once a day, as the towels often dried out in a matter of a few hours. Even if this method worked, the upkeep made this technique far inferior to the other two (in my opinion).

After 8 days, there was no visible root growth on the paper towel group. (Any new growth on the roots would be visibly white)

The Winners

Both water propagating and soil propagating worked very well. Let’s break down what happened for each one:

Remaining plantlets in the soil and water propagating groups as of December 9, 2020.

Water Propagating

With the water propagating treatment, plantlets began growing new roots within 24 hours. I simply left the plants be, checking the water levels about once a week. I’d say that within 14 days the plantlets were ready to be potted in soil.

Personally, this might be my favorite method since it is easy to gauge root growth. It was low maintenance and it worked. What’s not to love?

ProsCons
1. Easy and low maintenance
2. Can easily view root growth
3. Easy to assess when more water is needed
1. water lacks nutrients, so it is not sustainable long-term- you will want to eventually move the plantlets to soil
Pros and cons of water propagating

Soil Propagating

The progress of the soil propagating group was harder to assess. All I really had to go on was whether the plantlets felt stable (from well established roots). I had no idea how they were really doing until I pulled one up on December 9th to compare it with the water propagating group. I wasn’t a fan of the fact there wasn’t an obvious indicator when the soil needed more water. (Unlike the water propagating group, where you can see if the water level is getting low).

ProsCons
1. Easy
2. Plants have access to nutrients
3. No re-potting necessary
1. Cannot view root growth
2. More difficult to gauge when water is needed
Pros and cons of soil propagating

Something I wasn’t expecting was how different the roots grown in soil looked from those grown in water. The water propagated plantlets had long, healthy roots, but the soil propagated ones were much more…robust.

Root growth after 16 days for soil propagating group (bottom) and water propagating group (top)

Why do the roots look different?

At maturity, spider plants produce fleshy, tuberous roots. These tubers are enlarged roots that help store nutrients that can sustain the plant in times of hardship (sort of like our body fat, which helps store energy for future use- more on that in another post).

These are the roots of the mother spider plant. You can clearly see the enlarged tubers compared to the normal roots. These sections of root store energy and nutrients for future use.

I was having a hard time finding any research to explain the different root results between the propagating methods, so here’s my best guess: spider plants need access to nutrients in order to store nutrients (e.g. produce tubers). The plantlets that were propagating in water didn’t have access to any nutrients, meaning there was nothing to store in tubers. On the other hand, the soil propagating group *did* have access to nutrients. The enlarged size of the soil propagating plantlet roots makes me think that they were beginning to form tubers. I’m not sure what difference (if any) this will make in the long-term success of the plantlets.

Final Thoughts

Something to consider: the ultimate goal is to eventually move your plantlets to soil. At this point, I can’t say whether the differences I observed in root growth will impact the plants at all in the long run. (Perhaps I will have to make an update in a few months!)

Whether soil or water propagating works best is probably up to you- would you forget to regularly dampen soil? Do you want to avoid the hassle of moving the plantlets to soil after water propagating them? I’ll leave it up to you which method to use.

On December 9, I moved all remaining plantlets to soil.

Would you like to see me do a future update on the spider plants? Have you ever tried propagating spider plants? If so, how did it go? Let me know in the comments!

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