Providing water without watering


Most of you would have frowned while reading the title. After I posted a question to identify a pot I own, I thought it was time to counterbalance and throw in some information to contribute to this forum.

This post is dedicated to home-made humidity trays. Last winter I borrowed some booklets from the president of our local club. A couple of them were magazines from the French bonsai society. In one of them I found a very interesting article. The author visited a hobbyist in Japan who had a developed a system to water his cuttings and seedlings. It was titled “Arrosage sans arroser” which is roughly translated into providing water without watering. I already juggled with the idea to start takings cuttings and develop material myself from the bottom up. At the same time, my interest in companion plants started rising as well. I decided to take the idea to my dad, who would be able to develop the system I read about in the magazine. What follows are some photos of my setup.

This is the base of the system. The box is made from plastic. Beneath the iron screen, there is a cloth that stays damp. The iron screen makes it so that the plants have an even surface to stand on. It also allows me to clean the boxes out pretty easily, since it sits loose. The idea of this system is based on the idea of communicating vessels.

This tube is attached to the box. At this moment we have to rearrange it, since we moved to setup to another place. But I think the idea is clear. A tube full of water fills the box for about 3/4. I haven’t yet addressed the advantages of this system. What this allows me is to keep plants (and little trees) moisturised throughout a long and hot day while I am away. Moreover, it creates a “microclimate” because the cloth beneath the iron screen stays damp all the time. I can water newly established plants and cuttings without disturbing the soil too much. Last but not least, I can also feed my companion plants efficient by adding some fish emulsion in the tube. The plants get time to soak up the water, instead of just running through and quickly back out. I must say that I am very happy with this setup, even though it might not seem that spectacular.

And a small little plant that just started flowering

If there are any questions, feel free to ask! (I hope this was somewhat informative)

(Jonas Dupuich) #2

Thanks for the great info Stefan! This is timely as California recently imposed emergency conservation regulations.

I’ve started using saucers for my thirstier trees and love the idea of using larger basins to preserve - or in this case, provide, water.

In Japan I’ve seen large cement tables (see “Kita’s bonsai”), and I regularly use trays filled with lava or gravel (see “Keeping bonsai from drying out”), but I haven’t seen the approach you’ve outlined - this may be the year to give it a try.

(james) #3

Pretty cool system. Thanks for sharing it. I have a few questions for you. How do you control the rate of water flow out of the tube into the tray? Also, what is the approximate volume of the tube? Lastly, did you use landscape material as the cloth? You have got me thinking about setting up something like this using collected rain water.


The rate of water can be controlled in two ways. I either fill the tube partially (and pull it up so all the water runs out) or I pull it up partially (when filled completely). The box and tube are communicating vessels, so I can play around with pulling up or lowering the tube to my own needs.

Filling the tube completely takes about 7 liters of water. But keep in mind that the boxes were measured to my own needs. Based on the volume of the box, I calculated how much water it took to fill it for 3/4. Then I started playing around with diameter and the length of the tube. There is no fixed standard for this system, it has to be tailored to your own needs.

I just took something that was laying around at my dad’s workplace. It was a synthetic fibre cloth, normally used for some form of isolation. Anything that stays damp and isn’t damaging your plants works.

(Tim Shea ) #5

2/3s of my bonsai sit on some kind of shallow water filled tray or dish ,& have been for years during the summer ,