More orchids are killed by over watering than for any other reason. It begs the question, how much water do they really need? How long can an orchid go without water?
I know they grow slowly and react slowly to their environment. They also die slowly. I decided to see if an orchid needs to be watered regularly.
Orchids – Testing Their Water Needs
I decided to take one of my phalaenopsis and use it for this test. I took the plant out of its pot on 7/17/2015 and took all of potting media off the roots. The orchid had been in arborist wood chips – I wanted to see how well these worked as a medium. You can see from the pictures below that the roots were not in good shape. Wood chips don’t seem to work too well for orchids.
I set the orchid on my desk and waited. It was not watered or misted during the duration of the experiment. It was fairly close to an east facing window which gave it low light.
At the 48 day mark I started feeling sorry for the poor thing especially since I was about to leave for two weeks of holiday. I put it back into a pot with coconut husk and watered it. It did not get watered again for two weeks while I was away. When I returned, it was watered whenever the media was completely dry – about once a week.
For more about my watering technique see, Watering Orchids with Ice Cubes
The Results
The picture at the top of the post shows the orchid at the start of the experiment. The top leaves look quite turgid and it is growing a new leaf which is always a good sign.
The above picture shows a closeup of the roots at the start of the experiment. You can see that quite a few of the roots are rotting – they are the black ones. If left in the pot with the wood chips, further rot would have occurred and it would have started to have a water stress even in the pot. Even with such a poor root system there were no obvious signs of stress showing on the leaves.
After 24 days without water the orchid is starting to show signs of stress. The top three leaves still look turgid and the new leaf is still growing. However, the lower two leaves are starting to show wrinkles, a sure sign of water stress. It is normal for the phalaenopsis to start loosing the lowest leaf – they rarely have more than 4 leaves when grown in the home.
The green tips on the gray-white roots show that the good roots are growing. These seem quite healthy and are being used to pick up moisture from the air.
It is now 48 days without watering. All the leaves are showing water stress and the lower leaf has gone brown, allowing the plant to absorb its water. Even the good roots are now wrinkling as a result of inadequate water.
Even though there is some stress, the plant is perfectly healthy and very much alive.
At the 48 day mark the orchid was put back into a pot; this time with coconut chunks. It is a medium I am quite familiar with and know it works well for orchids. At 94 days the plant is growing well and the leaves have full turgor. The newest leaf is a good size which shows that the orchid did not encounter too much stress while it was growing.
For more about potting orchids see, Repotting Orchids
Orchids – Do They Need Water?
This orchid was not watered for almost 7 weeks. Over that time it slowly lost water, which can be seen by the wrinkling in the leaves, but it did not undergo extreme stress.
Clearly, you can leave an orchid for a couple of months without watering and it will survive. I don’t recommend this, but missing a couple of waterings will not kill an orchid.
It also shows how tough orchids really are. The only real way to kill them is with too much kindness. Be mean to your orchids – they will love you for it!
Very helpful article! I had to work from home since late March and the orchid a coworker gave me was left unattended since today, September 24. Office is not very humid but I’ll be darned if it wasn’t blooming and putting out new shoots when I picked it up!! Stress induced flowering is a wonderful metaphor for life – would that we could all be more orchid. I am so enamoured with this plant! Hope I don’t kill it with kindness now!
I’m a newbie, and I want to thank you for your helpful experiment–really good work! My orchids have just lost their blossoms and I’m leaving my eastern-exposure New York apartment for 3 weeks in December. I was planning to cut them back before that,repot them in larger pots (two are exploding out of their pots, while the other had too much moss but seems to be okay), and then water them heavily, leave them in a shadier spot in the same room, under a transparent plastic bag to maintain humidity, and have someone else water them once a week. From your article, apparently I don’t need to worry so much about watering them while I’m gone. But the plastic bag idea is because I’m very worried about temperature and humidity–the humidity in my apartment house drops to 30 or below in the winter,but it’s not practical to run a humidifier for three weeks (has to be refilled every day). Also, the forced-air heat in my apartment building has to be turned on manually to heat the room. I can regulate the temperature in another room, but it’s much darker.
So I have both a temperature and a humidity problem for three weeks. Any suggestions? Thanks so much for any advice!
I would just leave them alone – they will be fine.
Thank you so much for this! I grabed a few orchids that were on the clearance rack that were screaming my name to take them home and love them. I cleaned up their root system, but their moss medium was beyond usable. Being a spur of the moment buy, I had no planting media, and was a bit worried until I came across your post. Might even be good for them to dry out a bit after steeping in water for that long lol
Really informative, and nice experiment setup without any media at all.
Somewhat related, I have been growing Phalaenopsis with some roots permanently submerged in water for some years now. I have found it to be an excellent way to avoid the older leaves to hang semi-dried but alive. I always had that problem before, that is what happened if there was a too-long time lapse between waterings sometimes, which I always had once in a while. I could never make those green-but-half-dry leaves look shiny and healthy again.
Now I never have that problem anymore. Also, I typically have a higher number of healthy leaves on each plant. One has 10 healthy leaves, with number 11 on its way, but 6 to 8 is more normal.
I wrote an instructable that about the method: https://www.instructables.com/id/Orchid-Hydroculture-or-How-to-Water-Your-Phals-Onc/
Interesting article. I have started testing water culture for Phals recently. There is also a Facebook group for such culture.
At what level the orchid root stock progresses. Downside or surface sideways of the coconut husk?
Sorry – I don’t understand the question. Roots will tend to grow in all directions; some down into the pot, and some out into the air. Both are healthy roots.
Thank you for this. So helpful. By the way only one “o” in losing water.
Great info. I’m your typical guy that bought one at the store but had the insight to get help and not just take a wack at it. A few hours later and I’m good to go.
I am afraid my orchids ‘die slowly’ in our ‘conservatory’ which is really just a glass walled east facing room where because it is so nice we live in there most of the time. If an orchid flowers for me perhaps four times before it dies I am happy.
They are not sold over here with wood chips, just bark.
Orchids are not sold with wood chips here either – but I thought I would try them. Would be a cheap media.
I grow a few orchids most successfully in bark, in a self-watering pot with a wick. I’ve accidentally found that I can induce flowering by withholding water for a couple of months.
Stress is one way to induce flowering.
Most interesting and comforting. Kindly let us know soon how to get them to bloom.
That will be my next post on my other blog Garden Fundamentals It will be posted mid May 2016.
The key is to grow it correctly, giving it lots of light. Then give it a bit of stress – less water, and some cooling down.