If you’ve been drawn in by the spectacular patterns and bright colors of a rattlesnake plant, you may be surprised to learn they’re better known as Calathea. While there are many types of Calathea, they all share common demands for water and need similar handling. Watering these plants correctly is the most challenging part of their care. Even if you have a green thumb, you’ll need some equipment to give these houseplants the best treatment.
- When and How to Water Calatheas – The Essentials
- About Calatheas
- The Role of Water in Plant Health and Development
- When to Water Calatheas
- How to Water Calatheas
- Signs You Might be Overwatering Your Calatheas
- Signs You Might be Underwatering Your Calatheas
- Watering Calatheas FAQs:
- Wrapping Up
When and How to Water Calatheas – The Essentials
Calathea needs routine watering to ensure the soil never fully dries out. Yet, it should dry out to the top two inches between watering cycles to prevent root rot. This requires frequent checking to ensure you don’t mix the optimal time to water the plant.
Calathea is an entire genus of closely related plants that are all native to South America. Naturally growing among the roots of large canopy trees, these plants receive relatively little direct light but enjoy a high humidity environment.
They can be kept indoors successfully if watered with care since they don’t necessarily enjoy the low humidity levels in the average home. They’ll also benefit from a light fertilizer during the growing season and occasional pruning for a healthy growth rate.
The Role of Water in Plant Health and Development
Water is necessary for healthy plant growth because it provides pressure to the individual cells. When a plant is low on water, it wilts, slumping over visibly. The cells shrink and simply can’t keep the stems and leaves at normal pressure.
Water also carries nutrients from the soil into the plant, helping it create amino acids that it can’t make from photosynthesis alone.
When to Water Calatheas
Watering Calathea is challenging even for experienced plant keepers. When misted regularly and kept near a small humidifier, Calathea likely only needs watering once every week to two weeks. In a dry environment, it may need watering every few days.
The plant prefers to dry out slightly to avoid root rot but needs to stay damp below the first two inches of soil or will struggle.
Balancing the need for some drying with regular dampness takes some practice.
How Do You Know When Calathea Plants Need Watering?
Calathea plants do need to dry out slightly between watering cycles. Touching the top two inches of soil with your fingers and wait until they’re beginning to dry out but aren’t stiff or fluffy yet.
Don’t wait until the calathea plant wilts, droops, or starts losing color, or it may take weeks to recover.
How to Check When to Water a Calathea
The finger test will tell you when the top two inches are drying but not yet wholly bone dry. This is essential to know when to add more water.
Moisture meters can work well, but you’ll still have to figure out what measurements correspond to the plant’s needs based on touching the soil as well.
Weight testing the plant is less effective since Calathea stays damp enough not to change weight much when drying.
How Often do Calathea Plants Typically Need Watering?
Calatheas are usually watered at least once a week. If misted and kept near a humidifier, it may only need watering every 7 to 14 days.
Environmental Considerations That May Impact Watering Cycles
Keeping your home warmer and lower in humidity will lead to more watering for your Calathea. Placing the plant near a heating or air conditioning vent will also create these drying conditions.
Fast draining soil isn’t always the best choice for these plants either due to the drying effects. For more, see our guide to the best soil mix for Calathea plants.
Seasonal Considerations That May Affect Watering Cycles
Calatheas go dormant in the winter and need more water in the summer. Reduce watering to as little as once a month over the winter, based on the soil’s drying rate.
How to Water Calatheas
How you water a Calathea and what you use for the process matters as much as how often you do it.
The Fundamental Importance of Good Drainage
Since Calathea plants like to stay somewhat damp, they need good drainage, so the roots don’t rot due to standing water.
Their roots grow into leaf litter, and loose bark dropped by mature jungle trees in the natural environment. This material drains well, so mimic that texture in the potting mix for good results. Organic material is needed to act like a sponge and hold water.
Inappropriate drainage can lead to poor plant health which in turn may attract common Calthea plant pests and diseases.
What Type of Water is Best for Calatheas
Calatheas are very sensitive to fluoride in particular. It’s well-noted in commercial cultivation guides that these plants need filtered or distilled water to prevent dead spots on the leaves.
If you notice dead spots, switch the water you’re using. Letting tap water stand can reduce fluoride, but Calatheas are too sensitive for that trick. Rainwater can work well.
Bottom watering is better for a Calathea, but it does take some patience. Top-down watering can work, but you’ll need to apply enough water that it will likely overflow any saucers.
If top-down watering is the only option, pour the water in around the base of the stems and keep splashes off the foliage. Soak the entire soil by moving around the pot evenly.
Bottom watering is as simple as placing the pot in a bucket or container that’s bigger than it. Fill the container with water until it reaches 3/4ths of the pot’s height. Let the plant soak until the top of the soil is damp to the touch, then let it drain in a sink or tub until it stops dripping.
How Much Water to Add
Smaller Calatheas in 3 to 4 inch pots likely only need 8 ounces or so to saturate their soil.
Large plants nearly the maximum size of 2 feet in height will likely need closer to a quart or more to satisfy them fully.
What to Do with Runoff Water
If the plant is in a saucer or tray, make sure to pour off the runoff after watering. Calatheas are very sensitive to sitting in excess water.
Signs You Might be Overwatering Your Calatheas
Keep an eye out for these common signs that you might be overwatering your Calathea plants:
- Yellowing leaves
- Fading colors and patterns
- Translucent and soft leaves
- Drooping stems
- Discolored roots.
Signs You Might be Underwatering Your Calatheas
Conversely, here are some common signs to keep an eye on that indicate you might be underwatering your Calathea plants:
- Curled, crispy leaves
- Brown tips
- Yellowing leaf margins
- Loss of color and brightness
- Drooping and wilting.
Watering Calatheas FAQs:
Should you consider misting calatheas?
Calathea benefits from misting on a daily or every-other-day basis. Use a basic mister and use distilled or rainwater if possible to avoid brown spots on the leaves.
Will calatheas benefit from sitting on a humidity tray?
Humidity trays can add a little humidity to the air, but Calathea prefers more than these devices release. Using a small desktop-sized humidifier for an hour or two a day is a better technique for maintaining color.
What are the main things to keep an eye on in-between watering cycles?
Watch out for the plant losing vibrancy and color first. Fading and patterns disappearing into a green background indicate that the Calathea isn’t getting the right water.
What are the most common signs a Calathea plant needs watering?
Color loss and dry soil is the first sign, but Calathea also tends to droop, develop brown edges, and yellow over time.
What is the best way to water Calatheas?
Bottom up watering works best for these moisture-loving plants.
How much water do Calatheas need?
Each Calathea should be watered until water runs easily from the bottom of the pot, then allowed to drain.
Is it ok to get water on Calathea plant leaves?
While these plants enjoy misting, they don’t like water splashed on their leaves when watering.
What do I do if I over water my Calathea?
If the plant can’t dry out just by skipping a few watering cycles, try repotting it with a better draining mix.
Can I water my Calathea with tap water?
Avoid tap water to keep fluoride from damaging the plant.
Calathea plants enjoy a humid environment but don’t want the soil to stay damp all the time. Balance humidity and the watering cycle to ensure the plant gets enough water without drowning in its own soil.
Andrew is the Editorial Director at Petal Republic. He holds a BSc degree in Plant Sciences and has trained professionally at leading floristry schools in London and Paris. In amongst overseeing a global editorial team, Andrew's a passionate content creator around all things flowers, floral design, gardening, and houseplants.