How often should you water Phalaenopsis orchids?
One of the first objectives in orchid care is learning how to water your orchid properly. Both over-watering and under-watering are the two main causes of orchid death. When you learn to water your orchid, more than half your battle with orchid care is complete.
The other items that influence blooms, and good health, such as light, temperature, humidity, and fertilizer, do not influence the orchid’s health as much as how often and how much water you provide for your orchid.
Several factors will influence how often you should water your orchid, for example, the size of the pot, the type of orchid, the season of the year, the orchid’s condition, the potting media it’s planted in, and if the orchid undergoes a dormant cycle.
For example, a medium-sized Phalaenopsis orchid planted in a 5-inch pot needs to be watered every 7 to 10 days. Smaller-potted Phalaenopsis such as mini-Phals need a shorter interval in between watering, 4-5 days.
Orchid health is influenced by how much and how often you water. In this article, I’m going to focus only on how often you should water you’re orchid. Let’s look at each one of those conditions to determine how often you should be watering your orchid.
It’s trial and error sometimes, but if you follow these guidelines there is less error. The main thing you need to know is that each person’s climate and growing conditions are different, so don’t take a general rule and apply that to all your orchids. You have to test and see what works for you and stick to that, independent of what everyone says.
1. The Type of Orchid (Genera) Dictates How Often You Should Water
Since orchids are such a vast group of flowering plants, with over 760+ genera and 28,000+ species, growing in every continent except Antarctica, watering will differ for each of these.
Some orchids grow in hot, humid rainforest, others will thrive in desert conditions. Some have roots that dangle down into the top layer of moss near waterfalls, others grow in hot savannas with hardly any rain at all.
Most supermarket orchids that sell Phalaenopsis are what we call NOID, which means they have no identification. You won’t be able to know much about them since they do not have a species listed. In this case, assume that it comes from where most Phalaenopsis orchids come from, Southeast Asia or Australia. New Guinea and the Philippines are the two major countries where Phalaenopsis grow naturally by the thousands.
If you have a Phalaenopsis orchid, try to find out what species it is. Then you can research the growing conditions of that area and see the elevation, the precipitation index, the temperatures and the yearly climate change. I like to find sites that are not orchid related but just focus on temperature. (Source
) With this information, you can mimic those conditions (to the best of what is permitted indoors) so your orchid is happy.
By happy, I mean it will bloom and produce nice healthy leaves and roots.
On that site cited above, it said, “In the Philippines, an archipelago of thousands of islands, the climate is generally tropical maritime, with a relatively cool season from December to February, when the north-east trade winds prevail, and a hot, humid and rainy season from May to November, when the south-west monsoon prevails.
Between March and May, before the arrival of the summer monsoon, the temperature increases and reaches the highest levels of the year, especially in the center-north and in the interior of the larger islands: hence, in general the coolest month (or the least hot) is January, while the warmest is May.
In the north of Luzon, cool air masses can sometimes arrive from December to March, so much so that at night the temperature can drop to around 12/15 °C (54/59 °F). On the southernmost islands, close to the Equator, temperatures are more stable, and remain high all year round.”
In terms of temperature, that is what l follow when I grow my Phals indoors. But since it’s not the temperature that I am concerned about in this article, keep reading on those climate pages until you get to the relative rainfall. If by chance you find humidity levels, write that down too. Not all sites have specific information, but keep looking and researching until you understand the climate of where your orchid would live naturally.
I find it’s a great tool for future travel plans, too. My goal is to visit a whole bunch of countries where I’ve researched orchids. It’s a great pastime…
That same article said, “Relative humidity in the Philippines is almost always high as well, and makes the heat muggy, at least in the lowlands. Some areas (usually the eastern coast, facing the Philippine Sea), have an equatorial climate, ie rainy throughout the year
.” That is the type of information I want. One thing that is a common denominator in all these countries is that Phalaenopsis orchids always grow near a source of water.
That could be a river, a waterfall, a pond, or even a creek. They need high humidity and love water. If given one extreme to choose from, they’d prefer to have their roots a bit wetter than totally dried out for longer periods. In these climates, the average rainfall is plentiful, almost raining every day to every other day. How does that information translate into how often you should be watering your Phalaenopsis orchid?
Since you know (after research) that it will rain almost 208 days out of the year, you have to recreate that indoors. If you take only that information and disregard the rest, (such as the size of pot, the potting media, relative humidity, and airflow) you will be watering your Phalaenopsis orchid every day or every other day. The immediate results are clear signs of over-watering: root rot and shriveled leaves.
Soon the leaf turns yellows and drops. This happens because the other underlying conditions were overlooked. So, let’s take a deeper look.
Our first step in understanding how often to water your Phalaenopsis orchid is complete, but there is so much more to add to the equation.
2. Potting Medium Influences How Often You Should Water
Go back to the Philippines and observe where this Phalaenopsis orchid lives. It’s probably on a tree and its roots are exposed. There is abundant wind flow and hot air currents cause quick evaporation of any excess water that the rain brought.
Now, look at your pot. If it’s a supermarket orchid, it’s probably potted in a brownie-like media that was made for watering with ice cubes. This material was specifically made to absorb more water since ice cubes melt and trickle-down at a slower rate than the watering in the sink does.
In essence, the potting media is absorbing more water than the orchid would in nature.
When you take this aspect into consideration, it means you can do two things: 1) space out the watering, or 2) mount your orchid on a cork slab to imitate its natural growing conditions.
On a slab or any other mounting material, the orchid will need to be watered more frequently. Since they dry out more quickly, you can (and should) water them every other day or mist them every day. If you go this route, here is a complete guide to watering mounted orchids
that I wrote. It would be a good place to start.
If you are not into mounting orchids, then you’ll need to space out the watering a few days until the roots dry out.
Depending on your potting material, this time is shorter or longer. Below is small graph, but this is what I found out to be true in my conditions.
Not all the information will be true to your conditions, so again, please don’t take this as a rule, but a very forgiving guideline. Also, the guide below is for a medium-sized Phalaenopsis orchid, not for other genera, nor for mini-Phals. (Source
How Often To Water Phalaenopsis Orchids
A Mixture of All of the Above
What is your orchid potted in? After the blooms have fallen off, you’ll need to repot the orchid in a potting medium that is better quality than the store-bought one you received it in.
Only once in my life have I bought a grocery store orchid and it came in bark. I was pleasantly surprised. Usually, it’s the brownie-like mixture made of a mixture of peat moss and other ingredients. Take all that off and repot. There is a guide to repotting here
, which is a good place to start. Step two about answering how often to water your Phalaenopsis orchid is to understand your media.
If you are curious and have the time, take out a cup full of orchid bark (or whatever media you are testing) and keep it submerged underwater for one day.
Then let it dry out on your orchid shelf or by the window sill and note how long it takes to dry out completely. This is necessary to hydrate the orchid bark, since it has been in a bag for a long period of time and will absorb more than normally.
The next part of the experiment is how long it takes to dry out when only two cups of water are added to it. I say 2 cups, but test how much water you’d be adding to your normal routine. Then note how long that the potting media takes to dry out.
What you are trying to achieve with this experiment is to understand how your potting media reacts to your environment. Since the orchid roots will absorb the water (not all, but a lot) you’ll need to shorten the amount of time during the numbers of days you wrote down.
In the pictures below, one is a mini-Phalaenopsis orchid planted in pure sphagnum moss. I have to water it every three or four days.
The other picture is a Phalaenopsis orchid planted in a mixture of sphagnum moss, charcoal, perlite, and orchid bark and in a terracotta pot. I have to water it every ten days.
The media is the main influence in these pictures, but also is the size of the pot, which is my next point.
Image Credit: © 2020 Orchideria. All Rights Reserved.
With a bigger pot like this one, you'll need to water the Phalaenopsis more. Also, the terracotta will absorb more, increasing the time in between watering.
3. Pot size Influences How Often You Water
Phalaenopsis orchids planted in smaller pots will have less potting media that absorbs water, and therefore dry out quicker. Larger Phalaenopsis orchids have more places for water to adhere and more material for the water to be absorbed into, so they will retain more humidity. larger Phalaenopsis also dry out at a slower rate, which means you need to space out water cycles, with a longer drying out period.
The size of the pot directly influences how often you should be watering your Phalaenopsis orchid. The material also is important, since terracotta pots will absorb more water than the plastic slotted ones will.
This will directly interfere with how often you water your orchid. For example, I have a mini-Phal planted in a 2-inch pot, and a larger Phalaenopsis orchid, planted in a 6-inch pot. The airflow will quickly pass through the mini-pot, and it will dry out quicker.
The amount of time the water evaporates from the middle of the 6-inch pot is quadrupled, making the middle of the pot always soggy and wet. If you have a fan on constantly, that helps. Phalaenopsis like humid climates, not soggy, swampy ones.
This is where the problems with over-watering are a real pain.
Even though the top of the potting media will be dry, maybe even crunchy, with a bigger pot that doesn’t mean that the middle will also be dry. In most cases, it isn’t.
To properly evaluate if a bigger potted orchid is dry, you’ll need to insert a bamboo skewer (or any other type of soft wood like chopsticks, Popsicle, or barbecue kebabs) down into the middle of your orchid pot. If it comes out wet, don’t water yet. Wait another day.
You can also move the top inch of potting media and use your finger. Swipe your finger across the potting media an inch (2.5 cm) under the media and see if it comes out dirty. If yes, don’t water. The humidity makes the bark and the charcoal easier to transfer to your fingertip. If your finger is dry, then you can water.
Image Credit: © 2020 Orchideria. All Rights Reserved.
The balance here is that sphagnum absorbs a lot, but the small pot dries faster.
4. Your Orchid's Health Determines How Often It Should be Watered
Dehydrated orchids and orchids in intense recovery will need more water than normal orchids.
More than that, they actually need more humidity than the water itself, but water is also increased for unhealthy orchids.
Water has always had a way of curing the body, and plants are no exception. When you have an orchid that is unhealthy (to check the signs of a healthy orchid, look at this article
I wrote on the 13 signs that your orchid is doing fine) it will need more water.
There is a fine line here into over-watering.
Sometimes you might think that the orchid leaf is dehydrated because of deep veins or grooves in the orchid leaf. You provide more water, yet nothing happens. This is because there is no root system to absorb that water and the Phalaenopsis orchid can’t really do anything with the water you provided.
If the orchid has healthy roots to absorb the water, but is trying to recover from a broken leaf, or a spider mite infestation, then a little more water is better. Increase the amount slightly, but not too much.There is no point in trying to add more water to an orchid that has no roots, so in this case, you’ll need to water less often.
Humidity is going to be what saves this orchid, and not the amount or frequency of watering.
5. The Seasons of the Year will Determine How Often You Water
Remember in your original research of the place your orchid grows? Let’s use the Phalaenopsis again as our example. There is a monsoon season, where rainfall is daily. Then there are a couple of drier months. This coincides with the winter/summer cycles that we would experience in the United States.
The cooler drier season would be from December to February (which is my winter). So during these times I can hold back on watering, where I wouldn’t water as much as normal.
Don’t withdraw all water by any means, as you would an orchid in dormancy, such as the Catasetum or the Dendrobium.
Phalaenopsis love water, but during those months, they just love it a little less. From March to May, the monsoons come, and you can water more abundantly.
Phalaenopsis orchids do not have a dormancy cycle, but will recuperate for a few days after producing a flower spike. It is so minimal that you won’t need to change anything about your watering schedule.
Other orchids would have to undergo more change, since during dormancy they do not want to be watered and any water you provide will just stagnate inside the potting media.
6. Hotter Temperatures Require Frequent Watering
If you grow orchids indoors, your temperature should be around 70° to 75° F (21° to 23° C) year-round. In this case, you really don’t have to worry about adjusting the frequency of your watering schedule according to the temperature outside.
Since many of you are more fortunate than I am and can grow your orchids outside, then you’ll need to keep an eye out on the temperatures. Higher temperatures promote a quicker evaporation rate, and you’ll need to water your Phalaenopsis more frequently. Lower, cooler temperatures will slow down the evaporation rate and more water will stay trapped inside the potting media.
This is important to know. Around autumn, when the temperature starts to drop a bit, be careful that you aren’t over-watering. You can add a day or two during the drying out cycle.
If you want to know more about growing orchids outdoors, then read this article I wrote
. It is specially about Phalaenopsis and when (or if) you should bring them indoors.
To Summarize All that You’ve Learned
To know how often you should water your Phalaenopsis orchid, let’s take this short walk-through.
First, what size is it?
Small = Water less. Larger = Water more.
Second, what is it potted in?
Pure Sphagnum Moss = Water Less. Orchid bark = Water More.
Third, do you have good airflow, as a fan that runs all day?
Yes = Water more. No= Water Less.
Fourth, is your orchid healthy or dehydrated?
Dehydrated orchids need more frequent watering.
Fifth, is your orchid in winter or in a dormancy cycle?
Yes = Water less.
So it’s really hard to determine and give you a specific answer about how often you should water your Phalaenopsis orchids. The typical textbook answer to how often you should water your Phalaenopsis orchid is every 7 to 10 days, but that is a “cookie-cutter” answer, one-size-fits-all.
Start with that and observe your orchid. Follow the experiment in this article and adjust to what fits best in your growing conditions. Whatever you do, don’t use ice cubes and in this article, I explain why.
Another article to read is what water is best for your orchid: rainwater, distilled water, reverse osmosis water or tap water? You can read that article here.
In all, I want to reaffirm that you will get this right, no mater how many orchid have drowned or dehydrated before this one. We all are on a learning curve and have tons to learn each day. Just keep trying and you’ll soon get the hang of it. I wish you all the best in orchid care. Happy Cultivating!