Overwatered ZZ Plant: Important Steps For Saving Your Plant

How do you identify an overwatered ZZ plant and what can be done to fix the resulting problems? These, and more, are covered in detail in this article.

ZZ plants only need watering once every seven to ten days in the summer and as little as once a month in winter provided that they are not kept near radiators or air conditioners. Overwatering is a common cause of death as they are susceptible to root rot. Yellowing leaves can be the first sign.

Locate your trusty chopstick and insert it into the soil around your plant, right to the bottom of the pot. If it comes out with mud sticking to it, your ZZ plant is probably waterlogged. What do you do?

How To Rescue An Overwatered ZZ Plant?

Prepare Fresh Potting Mix

Soil mix for repotting

Get some new potting mix ready as you will have to repot your plant. Potting soil formulated for cacti and succulents is best because it drains well and won’t become waterlogged. Otherwise, you can make your own by blending perlite, sand, or vermiculite with regular potting soil. The mix should feel light and airy, not heavy and dense.

Put On Some Rubber Gloves

Don some rubber gloves to avoid any potential skin irritation from the sap of the ZZ plant. It is only mildly toxic and cannot be absorbed through the skin, but some people may be sensitive or experience an allergic reaction, such as an itchy red skin rash. The calcium oxalate in the plant is more of an irritant than anything else and won’t cause serious harm.

Remove The Plant From The Pot

Empty any water in the drip tray and carefully remove the plant from the pot. You do this by gently flipping the pot upside down and allowing the plant and soil to fall out into your hand. If you try to remove the plant by pulling on the stems, they are likely to break off, and you won’t achieve anything.

If the plant doesn’t want to come out at first, running a narrow scraper or knife around the edge of the substrate to separate it from the inside of the pot will usually do the trick. If it is a smallish plastic pot, you can also try gently squeezing around the outside to loosen the soil.

Once your ZZ plant is out of its container, inspect the roots and rhizomes. The underground rhizome looks like a hard, fat little bulb. You may need to carefully remove the soil around the roots to get a better view. Do this by softly brushing away as much of the substrate as you can with your fingers.

Then rinse the last of the soil particles away under the tap but make sure not to blast the plant with a jet of water. The roots and rhizomes are relatively fragile, and you want to avoid breaking any of them off. Use only room temperature water because it could kill the root system if it is too cold.

Users Also Read: How Often To Water ZZ Plant In Winter: Important Planting Tips

Inspect The Root System For Damage

If they are still healthy, the roots and rhizomes have a crisp white appearance. You can breathe a sigh of relief when you see this, as it means that root rot has not yet set in. Prune away the yellowed leaves around the base using sharp, clean scissors or a knife.

You can sterilize the knife or scissors with a bit of rubbing alcohol to ensure it will not transmit any more nasties to your ZZ plant. Sometimes dead leaves and stems will come out with gentle tugging but don’t use force.

If tugging doesn’t work, just clip the base of the stem with your scissors rather than pulling at it too hard. Ensure there are enough drainage holes, and place a few pebbles or pieces of gravel in the pot to prevent the potting mix from clogging them. Add a third of the potting mix and then insert the plant, adding more to top it up to the pot’s rim.

Wait around three or four days before watering.

Root Rot

If the rhizomes and roots of your ZZ plant are mushy and brown or black, you have a more serious problem as root rot has set in. You will need to use that sterile knife or scissors to snip away all of the mushy brown root material. The cuts must be sharp and surgical as you don’t want to be hacking away, leaving messy, jagged edges.

If the roots are rotting, you will also probably notice algae or mold growing around the base of the plant, accompanied by the foul musty smell of decay when you remove it from the pot.

Dead roots and rhizomes cannot recover, so you have to remove all of them. Hopefully, you will still have some viable underground parts that can regenerate your ZZ plant.

Pruning

Remove any mushy, yellow, or brown leaves and stems. You can cut them off or gently pinch them off with your fingers. If the remaining root ball is small, having too many leaves and stems at the top can overtax your ZZ plant because they require too much energy.

The pruning process can leave you with as little as a third of your original ZZ plant, but there is no hope of revival for dying parts. Your plant is literally in ICU and may not recover from extensive root damage.

Root rot is generally caused by fungal infections that multiply due to the excessively wet substrate. Fungi are everywhere, and you cannot avoid them in potting soil, but they only take over the root system if your ZZ plant is overwatered. Rotting roots make it impossible for the plant to absorb enough nutrients, oxygen, and moisture, so it will die.

Repotting

Repotting zz plant

The fungi will probably be growing all around the inside of the pot, so either use a new clean, dry pot or wash the old one in a mild bleach solution. Bleach kills fungi. Scrub the pot well and rinse it with fresh, clean water to eliminate any remaining bleach.

Never use the old substrate to repot your ZZ plant! Once the pot is dry, add some of the new substrate, insert the plant and top up with the rest of the substrate. If the potting mix is already moist, you don’t need to water just yet. If it is dry, lightly moisten it.

Place your poor mutilated ZZ plant in a shaded area where no direct sunlight can reach it. Remember that ZZ plants grow very slowly, so you will have to wait patiently to see if it recovers. Do not apply any fertilizer until you see new growth appearing.

Make sure you only water sparingly because the top two inches of the substrate should dry out between waterings. ZZ plants do not want soggy soil!

Also Check: Are ZZ Plants Toxic To Cats

Propagation

If your ZZ plant’s root system is beyond saving and you have some healthy leaves remaining, you can propagate a new plant from them. The easiest way is to propagate from leaf cuttings.

Carefully cut the leaves from the stems and allow several hours for them to callus. Insert the cut end of the leaf at an angle into very well-draining potting soil containing plenty of perlite or vermiculite. Alternately, use a mixture of half peat and perlite. Leaf cuttings do not need significant quantities of potting soil as it can retain too much moisture.

You can use a small pot or seedling tray to hold the substrate. Place the container in a warm, bright area out of direct sunlight. Not all the cuttings will take root, so it is best to use several rather than just one or two. Keep the substrate moist, not wet.

Wait for at least a month or even two before first checking to see if the cuttings have developed tiny roots. If you check the cuttings for roots too early or too frequently, they will die. It can take more than nine months in the correct temperature and light conditions before your cuttings start to put out new growth.

They will grow a bit faster in slightly warmer conditions, but you must prepare yourself to wait patiently for up to a year.

Conclusion: Dealing With Overwatered ZZ Plant

Many people overestimate a ZZ plant’s water requirements, and overwatering is common. The only visible sign of overwatering is when many leaves start yellowing. To properly assess the extent of the damage, you have to remove the plant from its pot and inspect the root system. Pruning dying roots, rhizomes, leaves, and stems and repotting in fresh soil is the only way to save it.

References:

https://www.gardeningknowhow.com/houseplants/zz-plant/propagating-zz-plants.htm

https://smartgardenguide.com/zz-plant-yellow-leaves/

https://thehealthyhouseplant.com/how-toxic-are-zz-plants-can-you-touch-them/

https://thehealthyhouseplant.com/help-for-an-overwatered-zz-plant-5-steps-to-recovery/