I am building a few earthboxes that I will use this spring for peppers and tomatoes, and it occurred to me that these might possibly be used on citrus. I wonder if a large earthbox from a half barrel would work.
Karl

If you are not sure about earthboxes, go to this site and it explains how to build them.

http://www.pathtofreedom.com/resources/index.php?option=com_weblinks&catid=27&Itemid=23

Open up the pdf file “Make Your Own Self-Watering Container/Earthbox” and find page 32. Now that’s what I am talking about, but maybe a larger container.
Karl

You can make it work for citruses if you are lucky. My experience told me it doesn't work if you use them as they are. There are other things you need to be aware to make it work.

One of the greatest drawback that I have experienced is that when potting media or other organic matter debris falls into the water up to a certain amount, it rots and smells very badly. Phytopthora root rot instantly killed my Calamondin this way. Done that.

As these submerged potting media particles decay under the water, it causes anaerobic conditions that even a fully open container will not help. One way to overcome this problem is that you will have to aerate the water reservoir. No matter how many holes you have, the water will not get oxygenated enough if you have a big load of organic matter falling into it. When you have aeration of the water, it now becomes similar to a hybrid hydroponic system, and that one works very very well. You can buy the water aerator in the fish pets and aquarium section of the store, these are very cheap devices too.

Another way is to make sure you clean the water of the debris. If you detect foul smell, take all the water out, sterilize the reservoir, and then reload. But that really is too much work.

And if you have time to build such earthboxes, reconsider building a good hydroponic system that circulates and aerate water. It just will cost a tiny tad more, but will work wonders and have been proven. It is best with a hybrid system. Just a little modification in piping to connect those earthboxes to a water pump and aerator should reward you with even better plants.

Is there another way of opening a pdf file?
Every time I tried to open it my computer freezes and then automatically ask me to buy the pdf adobe acrobat 8 pro model for $429.00
I am not willing to spend that much to see a picture here.

Benny download this http://www.adobe.com/products/acrobat/readstep2.html

Regarding the soggy soil problem with earthboxes: you can avoid this by using wicks (poly rope works fine) to transfer the water from the reservoir to the soil. I created "self-watering" beds in this manner with a wick for every square foot of soil. They work well for summer vegetables. Regular earthboxes (using the soil column as a wick) also work well for summer vegetables, despite the anaerobic "stink" that JoeReal describes.

That being said, I read on the four wind growers site that "self-watering" containers are not recommended for citrus, because citrus prefer infrequent, deep watering. I have not tried it myself.

Cheers,

Ed.

I may experiment with a small aquarium air pump to keep the reservoir oxygenated. A little hydrogen peroxide may also help.
I was suspicious of the earthbox for a long time but the testimony on many websites is very positive for growing vegetables. I have not found any comments about growing trees this way except that picture of the banana tree in the pdf instructions that I posted earlier.
Karl

I might argue that a banana "tree" is quite different than a citrus. Bananas are built to grow like crazy for perhaps one year or 1.5 years, then flower, fruit, and die (of course they may send out pups).

Bananas thrive in self-watering containers, especially if you either fertigate with a low concentration (say 200 ppm N) fertilizer, or side dress (along the perimeter, assuming the plant is centered). I have a basjoo growing in my office in a self-watering round pot that has absolutely taken over the joint.

One warning, the self-watering containers (if used as directed) never get "flushed", so salt buildup can be a problem if you are growing something in them for more than a season. Every few months you should flush from the top, if you can, to reduce the buildup.

Cheers,

Ed.