Are you saying changing existing plants to rootmakers is pointless Millet?

No, it is not pointless. However, the transplant into an air root pruning container should be done as soon as possible. Citrus trees purchased from Four Winds Growers are shipped bare root, this makes it easy to carefully spread out the root system in all directions, in a more or less horizontal position, and then carefully transplanted so that the roots are kept in that direction while adding the new medium. By doing so, the roots will grow toward the ridges and be air pruned. Because Four Winds Growers trees are shipped bare root, I prefer to purchase their smaller 1 year old trees, as these are easier to transplant, and wind up making a denser root system than the larger 2 year trees. When roots are air pruned, they produce 3 or 4 new side shoots starting approximately 4 inches back from the root tip. Where one root was before pruning, now there are 4 roots. For trees that have been grown in a common nursery container, all the circling roots need to be pruned away, then 1 to 2 inches of the outer root ball CAREFULLY removed so that a couple of inches of roots extend out. When transplanting into a air root pruning container the root extensions need to be kept horizontal while adding the new growth medium. Care must be taken so that the exposed roots do not dry out while transplanting. - Millet (1,221-)

Millet,
For bare root trees (and any bare root trees in general), is there any benefit to soaking them in a solution of rooting hormone? I know it's typically used to cause cuttings to take root, but I honestly haven't heard of using it to cause any improvement in an existing root system.

Phillip

Can anyone comment on these Smart Pots?

http://www.igrowhydro.com/detail.aspx?ID=6395

This place is literally five minutes from my place.

They also sell perlite and coco coir/fiber. Not chips.

http://www.igrowhydro.com/searchresult.aspx?categoryid=192

Will coir/fiber work just as well as chips?

Dauben, interesting idea. Really I don't know if there would be any benefit or not, but my guess is that there would not be any benefit. - Millet (1,218-)

This was a very interesting thread to read. Does growing citrus trees from seed in such containers shorten the time to fruiting maturity? If so by how much? Thanks.

Just as an update to my experiment with landscape fabric being used as a root pruning medium. It was a failure (at least with the fabric I was using). The roots just grew through the plastic fabric. Then again, part of my failure was probably because I didn't keep them off of the ground and roots were allowed to grow through into the soil.

Phillip

Updating an old thread re: this same topic with my experience. I was testing Fanntum brand and Smartpot brand fabric containers the past two years on citrus and other fruit trees.

Quote:

Then again, part of my failure was probably because I didn't keep them off of the ground and roots were allowed to grow through into the soil.

This happened to me with both types of fabric containers holding vigorous apple & pear rootstocks, but not citrus (yet). The roots grew straight through the bottom when placed on the ground. It became obvious when it happened as the tree then "took off" and had massive growth surpassing the others around it.

The Fanntum containers were so much nicer to move around with the handles and make excellent temporary containers when I intend to plant in-ground. For example, I'll size-up a tree in a container before deciding to plant it in the ground. It works very well. Ditto if I'm planting it in ground, just temporarily to size it up for a couple years before removing it back into a container. The fanntum metal framework makes removing the tree so much easier. Granted, these activities are outside the norm for most home gardeners.

However, I'm on the verge of giving up on fabric containers altogether for the fruit bearing trees. When the roots expand to the edge of the container the stress on the trees is evident. In my climate, the mix edges dry out too fast and it's hard to water the outside "ring" to keep it evenly moist with the inside. This makes excessive root "pruning" (ie. dying) and the tops of citrus start dying back immediately and fruit drop. Whereas with the Rootmaker containers only the roots that reach the hole "prune points" die-back, creating a staggered approach.

With the fabric, one tree did die-back then flush again nicely (as the roots should've back-branched per the 4inch rule) and then fruit. It was obvious the timing of the "root pruning" seemed important, as well as the vigor of the stock and condition of the existing rootball before placing into the container.

But my experiences make it difficult to recommend fabric containers to home growers who intend to use them for fruit bearing trees in a dry climate.

I really like RootMakers Air Root Pruning containers. 100 percent of my tree are growing in them. Let Me Add One Note: Even when growing in a RootMaker Air Root Pruning Container, the tree cannot be left to over grow in the containers. When it is time to transplant into a larger container, or when it is time to root prune and replace back into the same container it has to be done on time. A tree can still become root bound in Air Root Pruning Containers, just like in standard nursery containers. - Millet (584-)

Millet,
You said that 100% of your trees are growing in rootpruner containers.
What is the largest size you have?
After reading through this forum I have thought about trying them again.
Working at the nursery that I do, my boss has some lying around, they are three gallon pots. I have tried it before, he has too,and neither of us are thrilled with the results we got. There may have been something that we were neglecting, so I might be the guinea pig to try again.
Darren

Hey Darren. I have a Chandler Pommelo growing in my largest Root Maker air root pruning container. It is 2.25 ft. tall and 7.8-ft. in circumference, filled with a CHC/peat medium. A container does not need to be any higher, because 90 percent of a citrus tree's root system is in the top 20 inches soil or container. - Millet (462-)

That is a big container, guessing about a trade 30 gallon.

Do you know if this 2.5 foot tall rule also applies to other non-citrus fruit trees?