Hi – I’m wondering if it is time to transplant my two ZZ plants.
– a few of the branches are having a hard time staying upright, and look like they’ll break off from the rhizome
– a few of the new shoot branches stay light green and sort of whither (trimmed those off)
– some existing branches turn yellow with brown edges (trimmed those off)
– should I trim as I’ve been doing?
– if it is time to transplant, how much of a bigger pot, what type of soil, should the rhizomes be covered?
Thank you in advance, Robin
Thank you for your question on your ZZ plants (Zamioculcas zamiifolia), which led to some very interesting research. I do not usually quote Wikipedia, but this was so interesting it was worth repeating. (I have taken out the hyperlinks, but if you go to Wikipedia, you can follow them):
“Zamioculcas is a genus of flowering plants in the family Araceae, containing the single species Zamioculcas zamiifolia. It is a tropical perennial plant, native to eastern Africa, from southern Kenya to northeastern South Africa. Common names include Zanzibar gem, ZZ plant, Zuzu plant, aroid palm, eternity plant and emerald palm.”
The ZZ plant is a fabulous houseplant that seems to be able to survive the worst neglect. It likes indirect sunlight from a south-facing window, but can survive in a lot less light than that. The fact that your leaves are browning indicates that the plant may not be getting enough light (or that you are watering it too much). Do trim off any browning or dying leaves.
The roots of the plants have succulent rhizomes (the white bulbous part of the root that you can see in your photo trying to jump out of the pot) that store moisture, making it very drought resistant. It can grow three to five feet in height, and can flower in summer, but it would need to be looked after very well to achieve these lofty heights.
The transplanting of the ZZ plant seems pretty straight-forward, and it does look as though yours requires transplanting. Now (early spring) is a good time. Transplanting gives you the advantage of being able to split your plant in two. They make wonderful gifts. If you keep it intact, then you will get a bigger plant. There are many YouTube videos showing you how to do it. But the one trick seems to be that if the plant is very root bound, then you may take some very sharp scissors and cut the plastic pot, or break the ceramic pot, to free the plant.
The ZZ plant likes being grown in very light soil, so you could add some vermiculite or sand (or cactus soil mix) to the potting-soil mix. The pot size should not be much bigger than the pot it is growing in at the moment. I saw someone on YouTube using chopsticks to make sure the new soil that is being placed on the sides of the pot went right down, ensuring no big holes. It seemed like a great idea. Water the plant/s well so that water seeps out of the pot. Let it sit for 20 minutes, and then remove it from the puddle. It needs to dry out in between waterings. Water it about every 3 weeks or so, at the most.
My last point is please do not forget that your ZZ plant is poisonous to animals and people. If you have dogs or cats, please make sure they cannot nibble on its leaves.
There is more information on this previous posting from the Toronto Master Gardeners: