To care for a ZZ plant place it in bright indirect light, water when the top 2 inches of the soil are dry, and repot every 3 or 4 years with a well-draining soil mix. Apply a fertilizer at half strength during the Spring and Summer.
| Growing Conditions: | How to Care for ZZ plants: |
|---|---|
| Light: | Bright, indirect light. |
| Watering: | Water when the top 2 inches of the soil are dry (typically once every 2 weeks in Summer and once every 3 or 4 weeks in Winter). |
| Temperature: | 59°F to 100°F (15°C to 38°C) is optimal for growth. |
| Humidity: | Can tolerate both high and low humidity. |
| Repotting: | Repot every 3 or 4 years. |
| Potting Soil: | Use a well-draining mix of 80% houseplant potting soil and 20% perlite. |
| Fertilizer: | Use a general houseplant fertilizer every month in Spring and Summer at half strength. |
| Pruning: | No need to prune. Cut back in the Spring to a desired shape if necessary. |
| Toxic to Pets: | Can cause irritation to cats and dogs if ingested. |
| Height: | Grows to 1 meter (3 feet) at maturity. |
| Propagation: | Propagate from leaf and stem cuttings in the Spring. |
About ZZ Plants
ZZ plants (Zamioculcas zamiifolia aka emerald palm) are native to East Africa, growing primarily in Kenya, Malawi, and Mozambique and thrive in seasonally dry tropical biomes.
ZZ plants have specifically adapted to growing in dry conditions with thick waxy leaves that reduce transpiration and thick stems and rhizomes that store moisture to survive periods oof drought.
ZZ plants grow to a maximum height of 1 meter (3 feet) at maturity but they typically grow very slowly and take may years to reach this height which is another adaptation to growing in an environment with fewer readily available resources.
ZZ plants may only grow less than 4 inches a year but this depends on light and fertilizer.
There is also scientific evidence that ZZ plants can also help purify the air in your home.
Are ZZ Plants Easy to Care For?
In my experience, ZZ plants are the easiest houseplants to care for as they thrive on neglect. ZZ plants can go for months without water, grow in full shade, and even cope with being pot-bound without suffering adverse effects. ZZ plants are the ultimate low-maintenance houseplants for beginners.
Light Requirements
The best for a ZZ plant is in a room with lots of bright, indirect light. ZZ plants scorch brown in direct sunlight so do not place it on a sunny window sill. ZZ plants can also grow in shadier rooms although the rate of growth will be much slower.
I personally have my ZZ plant in a South facing room, set back from the window so it can benefit from the bright light without encountering scorching direct sunlight and it is thriving.
I personally recommend rotating your ZZ plant by 1/4 every time you water, to prevent the plant from growing sideways. ZZ plants always grow towards the strongest source of light which can cause excessive sideways growth.
You can move your ZZ plant outdoors in the Summer so it can benefit from brighter light and more hours of sunlight. However, it is important to move the ZZ plant back indoors if the temperature at night is forecast to dip below 60°F (15°C) as cold temperatures can harm tropical plants.
Wipe the glossy leaves with a damp cloth every few months as the leaves can gather dust. This helps increase photosynthesis and increase the growth rate of the plant.
How Often to Water Your ZZ Plant
Water ZZ plants every 2 weeks in the Summer and once every 4 weeks in the Winter. ZZ plants in bright warmers rooms have a much higher demand for water then plants grown in deep shade. Always allow the top 2 inches of soil to dry between bouts of watering.
I find the best way to determine whether your ZZ plant needs watering is to test the soil with your finger to a depth of 2 inches. If the soil feels dry, then this is the perfect time to water. I you can detect any moisture delay watering until it is dry.
I personally pick my ZZ plant pot up periodically after watering to assess the weight and therefore the rate at which the soil is drying out as a way to tell when the plant needs watering.
I would personally recommend not using a moisture meter as I have used a lot of them over the years and find they are not always accurate. Given the ZZ plants sensitivity to overwatering, an inaccurate reading that does not reliably indicate when the soil is dry could cause the plant to die if the soil damp for too long.
What is the Best Way to Water ZZ Plants?
In my experience, the best way to water ZZ plants is to either water from the bottom or submerge the rootball in a basin of lukewarm water for 20 minutes before removing and allowing excess water to drain away.
You can water successfully by watering from the top as you would most plants as long as you soak the soil and ensure that it is evenly moist.
The reason I find it is best to water from the bottom if because, as ZZ plants do not need frequent watering, the potting soil can dry out and bake hard due to heat and sunlight. This causes the soil to turn hydrophobic and repels water off the surface of the soil without infiltrating properly and reaching the roots where it is required.
Filling a saucer underneath the pot and watering from the bottom allows the soil to draw up moisture more evenly which ensures the roots can access the water they need.
I must emphasize it is important to empty any saucers or trays underneath the pot of excess water after 30 minutes or so as perpetually damp soil causes root rot.
Signs of Overwatering:
- Drooping foliage.
- A bad smell coming from the roots and potting soil.
- The leaves can turn yellow or brown (depending on the extent of the overwatering).
- The stems develop a soft mushy texture.
- Reduced rate of growth.
Your ZZ plant is far more likely to suffer from overwatering the underwatering. Reduce watering immediately allowing the soil to dry out between bouts of watering.
Signs of Underwatering:
- Wilting foliage.
- The stems appear thinner and shriveled.
- Leaves appear yellow.
- The pot feels light.
If you suspect the ZZ plant is under watered then place the pot in a basin of water for 20 minutes so the soil can properly hydrate.
(If you have any problems with your ZZ plant read my article, How to Revive a Dying ZZ Plant).
Temperature and Humidity for ZZ Plants
ZZ plants are native to Kenya and prefer warm temperatures with 59°F to 100°F (15°C to 38°C) being optimal for growth. The cooler the temperature the slower the rate of growth. ZZ plants cannot tolerate cold so move your plant to a warm location if the temperature drops below 50°F (10°C).
ZZ plants can cope with warm temperatures very well and do not mind being next to radiators or other indoor sources of heat. They also cope very well in air-conditioned rooms as they enjoy low humidity.
There is no need to mist ZZ plants but I have found they cope well with a range of humidity as one of my ZZ plants grows well in a relatively humid bathroom.
How Often to Repot Your ZZ Plants
ZZ plants are relatively slow growing so they only need repotting every 2 to 3 years. ZZ plants tolerate being root bound but they do need repotting if you can see roots protruding from the soil. Always repot ZZ plants in the Spring.
I have personally found the ZZ plants that I keep in brighter rooms and fertilize more often need to be repotted every other year whereas ZZ plants kept in a shady office space without much light can go 3 or 4 years without repotting.
Best Pots For ZZ Plants
The best pots for ZZ plants are terracotta pots as they are breathable and allow the potting soil to dry out more evenly whereas ceramic or plastic pots are impermeable which means the soil dries out more slowly around the ZZ plant’s roots.
Whilst terracotta pots are my personal favourite pots for repotting ZZ plants, they can grow in any pot soo long as there are drainage holes in the base.
I recommend to avoid using plastic pots as they can be too light in weight. ZZ plants are tall plants and can become top-heavy, meaning a light plastic pot is more likely to topple.
What Kind of Soil Do ZZ Plants Need?
ZZ plants naturally grow in stony soils in their natural habitat with fast drainage and low fertility. Therefore to grow ZZ plants successfully it is important to recreate these conditions by planting them in a potting mix of 80% potting soil with 20% perlite.
The perlite increases the porosity of the soil which creates space for moisture to drain efficiently and also decreases the fertility of the soil (as perlite does not contribute nutrients to the soil), thus effectively replicating the preferred soil conditions in the ZZ plant’s natural habitat.
The perlite can be substituted with horticultural grit or sand if necessary.
The Best Fertilizer for ZZ Plants
ZZ plants are used to relatively low-fertility soil, but you can increase the growth rate and size of the leaves by fertilizing once a month in the Spring and Summer.
Use a fertilizer an ordinary houseplant fertilizer at a half concentration as full-strength fertilizer is designed for plants that are accustomed to high fertility soils with faster growth rates then ZZ plants.
This is the fertilizer that I personally use.
Pruning: How and When to Prune Your ZZ Plant
There is no pressing need to prune your ZZ plant every year, particularly as they are relatively slow-growing. However, if you do want to reduce the size of the ZZ plant, prune back the branches in the spring to a desired size with a sharp pair of pruners.
My ZZ plant grows around 4 inches per year and I have only pruned it back once slightly in 4 years.
What I have found from my experience working in a garden center is that how quickly and how often you need to prune directly correlates with how brightly lit the room is and whether or not you use fertilizer as I have observed some ZZ Plants grow very slowly in dimly lit offices that have never needed pruning.
Spring is the best time for pruning ZZ plants as this is when it is most resilient to stress, but you can prune successfully at any time of the year.
Is the ZZ Plant Toxic to Cats and Dogs?
Zamioculcas zamiifolia is toxic to cats and dogs and contains insoluble calcium oxalates which can cause irritation to your cats and dog’s mouths if ingested, so I would either keep it out of harm’s way or look for another houseplant if your pets have a habit of consuming houseplants.
Spider plants are good, safe, pet-friendly houseplants.
Propagation
ZZ Plants can be propagated from both leaf and stem cuttings. The best time of year to propagate is in the Spring as the cuttings are far more likely to develop roots quickly when they are in active growth, although can can propagate at any time of year you may have a lower rate of success.
I personally have had the most success by propagating from a stem cutting into water in the Spring.
I find it is best to take a cutting of at least 6 inches and strip the leaves off the bottom half submerging the bottom 3 inches in water (using a jam jar).
The cuttings usually develop roots that are around 3 inches long within 4 weeks at which point you can transfer the cutting to a potting mix of 80% compost to 20% perlite and care as normal.
Here is a helpful YouTube video for a visual guide to propagation: