Is it moist? The brown spots are blemishes and not a cause for concern. Watering Read on to learn more.When you overwater ZZ plants, as with most plants, root rot may ensue.When too much water happens, the roots can no longer uptake nourishment properly, and this causes yellow leaves.To determine whether overwatering is the cause of your zz plant problem, simply check your soil.If you poke your finger into the top inch of soil, and it is wet, overwatering is likely to be your problem.To water your ZZ plants correctly, you should allow the top 1” inch of growth medium to dry completely.Pour water through the soil just as you would with a cactus or succulent.Don’t allow the plant to stand in water for any significant period.Be sure to tip any excess water out of the plant’s drainage saucer.Even though drought-resistant ZZ plants don’t need a lot of water, they do need some!If you have neglected your ZZ plant for an extremely long time and the soil has become completely dry, your plant will suffer and will let you know with yellow leaves.Soil feeling dry to the touch and a pot feeling abnormally light when you lift it indicates a need for water.Give your plants a good soaking, but don’t fertilize excessively dry soil.If you want to provide fertilizer, wait until the next appropriate watering time and use a diluted (half strength) solution.It’s not possible to recommend a precise watering schedule because every situation and the setting is different.The amount you will need to water your zz plant depends a great deal on some factors including:The more light, heat, and air circulation your zz plant receives, the more water it will need.Dimly lit, humid; still settings will require less water.If the soil you are using is heavier than is ideal, your plant will need less moisture.If you have an ideal, light, airy substrate for your plant, you’ll need to water a little more often.Generally speaking, weekly watering during the zz plants growing season (spring, summer, and autumn) and twice-monthly watering during the winter should be all right.Zamioculcas is hardy and undemanding, but they do need a bit of fertilizer from time-to-time.Choose a water-soluble, balanced houseplant fertilizer and mix it up at half strength.Fertilizing a couple of times a year (once early in the spring and once around mid-summer) is an ideal schedule.Yellowing leaves are sometimes caused by too much nutrition or too little (nutrient deficiency).If you have been fertilizing your plant excessively, give it a rest.Give your plant a thorough watering allowing fresh, clean water to flow through the soil for several minutes to rinse out excessive fertilizer.If it’s been a while since you’ve repotted your ZZ plant, starting over again with the fresh, new potting soil will also take care of problems caused by either under fertilizing or over-fertilizing.Another cause of leaves yellowing is excessive light.Zamioculcas like to be in partial shade or areas with moderate indirect sunlight.If your plant is receiving more than four hours daily of direct sunlight, it’s too much.If you believe excessive light is causing your plant’s problem, naturally you should relocate it to a setting providing gentler lighting – hint try (low light).Alternately, if relocating the plant is not possible, you may wish to put a sheer or lace curtain over the offending window to provide some shade.ZZ plants are winter hardy in USDA hardiness zones 9 through 10.These plants can tolerate temperatures ranging from 50°-90° degrees Fahrenheit (10° – 32° C), but wildly fluctuating temperatures will cause the plant to suffer and the leaves to yellow.Ideally, you should keep your plant at comfortable room temperature during the day and don’t allow the temperature to drop below 50° degrees Fahrenheit (10° C) at night.Plantcaretoday.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.comBy entering your email address you agree to receive a daily email newsletter from Plant Care Today. About 1 1/2 months ago I noticed the tips on a couple of leaves on one of the younger stems started turning yellow. ZZ stems fall over. That is normal, too. Because the ZZ-plant flowers are covered with its leaves as they grow along the base of the stem. As previously said, this plant really doesn’t need much care and it will be the best if you just forget it for a while.