Just curious which people prefer. I know that Millet prefers CHCs, but Al over at gardenweb seems to strongly prefer PBFs. What are the pros and cons of each? Thanks.

-Brett

Brett, both CHC and pine bark are very good ingredients to add to a growth medium. In the right amount, both give excellent aeration and drainage. You really can't go wrong with either one. I prefer CHC because:
1. CHC last 3-5 times longer than pine chips before repotting must be done. Pine mediums need to be replaced every single year.
2. CHC have the absolutely perfect 6.5 pH.
3. CHC hold 3 time more water than pine does. Up to 7 times their weight, while still providing excellent aeration.
4. CHC cost the grower much less money over the long run.

Between the two ingredients there is no right or wrong.

Millet

I use pine bark because I get most of it for free and it works well. I am out in the woods a good bit and I pick up slabs of bark from dead trees. I crumble the bark by hand so that the largest pieces are about 1 inch chunks and then add peat moss or potting soil whichever is handy.

Bret, the question is not whether coconut husk chips, or pine bark chips are the best product. Both products provide much the same benefets. Those benefits are aeration and drainage. When a tree is planted into a newly mixed medium utilizing either pine or coconut chips the tree preforms well, because the roots have plenty water, and plenty of oxygen. Further, due to the good porosity and the lose texture of the medium, toxic soil CO2 which is given off by the tree's citrus root system can easily diffuse out of the medium and back into the atmosphere.. However, as time passes all mediums of any type begin to degrade, compact with each watering. The porosity of the medium gradually is reduced, causing a lost of vital oxygen, and equally as bad, a build up of "soil"CO2 to toxic levels. When bark is used this degradation is completed in approximately 12 months. There is an old saying in the commercial nursery industry....."A containerized tree either needs to be sold, planted in the ground, transplanted into a larger container with new medium, or thrown away by the end of the year". Due to cost and fast turnover commercial nurseries primarily use bark. When the "chunk" portion in the medium blend is coconut husk the same scenario happens; only not over one year's time but over 5 year's time. Therefore a CHC tree is transplanted once in the same time frame that a pine bark tree is transplanted 4 or 5 times. Added are the higher water holding capacity, and the exact pH for proper tree growth. I hope this answeres your questions. - Millet

Millet,

Thanks for the response and I completely understand what you are saying. It is always interesting how different people's opinions can be on subjects as seemingly simple as this. I personally have changed over the past year the majority of my citrus and tropical plants in pots to a CHC-based mix.

Interestingly, the person considered the container gardening guru on the gardenweb site (Tapla), seems to feel strongly that pine bark fines are a superior product. He states that the degradation rates between PBFs and CHCs are no different. Also, he did a direct to direct comparison between the two when growing snapdragon and Coleus and found that the biomass was significantly greater in the PBFs (http://forums2.gardenweb.com/forums/load/contain/msg06134221751.html).

Although, it is difficult to translate these results directly to citrus, it is interesting to see the differences of opinions between different people. Being the experimenter that you are, I would love to see you do a head-to-head citrus grow-off between the two mediums (degradation rates not withstanding).

I greatly appreciate your expertise and advice. Thanks.

-Brett

Brett, I have used both and not seen much difference in growth or watering frequency. I do not see the 1 year degradation that Millet suggest in the pine bark that I use. One difference may be the fact that I use bark that is free of the cambium. Even when I do use bagged pine bark, I pick out the cambium pieces and discard them--something that would be labor intensive on a large scale, but I believe eliminates the component that does decompose within a year.

Over the millennia coconuts have migrated (floated) across the oceans of the earth to every part of the tropical world. Because of nature's special gift, the coconut can easily float on the seas for years, until by fortune it washes upon a friendly shore. In its circuitous water journey, the simple coconut arrives at its destiny in just about as good a physical condition as when it started. It is an amazing substance. An ability that wood fibers just can't match. - Millet.

Millet, I am not saying that coconut husk is bad--I just said I do not see much difference in durability here. Wood fibers do rot rapidly if kept moist, but Pine bark is not the same as wood fiber, pine bark is full of lignins and compounds that resist degradation and if all wood and cambium pieces are removed, the media itself will last several years. I do repot my trees about once a year--to increase container size if needed and prevent the roots from circling.

Skeet, please don't take any part of my posting as being written, in response to what you have posted. I would have posted them whether you wrote a single post or not. My posting are meant to be stand alone postings, without any regard to others. I agree with most of what you write, not only on this subject, but generally in most all matters. Sorry you thought that my writings were in any manner in competition to yours. The medium you use is much like the number one container mix used by the commercial nursery industry in the USA for trees and shrubs, which is 3 parts conifer barks, 1 part peat moss and 1 part concrete sand. More of this blend is used than any other formula. It is inexpensive, provides all the ingredients of a good potting mix, and has a life durable enough for the retail industry. Due to the extra expense of coconut, as compared to barks, I doubt that the above nursery formula will change any time soon. However, CHC has now taken over the orchid industry, due to its long durability. No need to worry about my writings. In fact I might have one more posting on this subject after I am able to read the GW link that Brett has provided. Take care. - Millet

After reading the link provided, concerning Tapla's investigations, I find that I would have to many areas of disagreement, to put into a posting on this forum. Such as 6+ pH being termed a "high" pH, and even the absence of many basics. It's probably best to just let life go on. - Millet

I just read the link Brett provided and the picture in that link shows a little of what I have been trying to point out--most pine bark or pine bark mulch has a significant amount of wood and cambium pieces that do degrade in a yr and turn to mush. However, if you can get pure bark like I do, it will last much longer. I do use a pretty large size material like that in the picture, but the bark in my case is much thicker--1/4 to 3/8 in thick for some pieces--similar to what you see in the pictures that Meyer Lemon posted.

I've read a lot of Al's stuff over at Gardenweb and have learned much from him, but on coconut media we will have to disagree.

I've used medium pine bark nuggets (bagged commercial stuff) and medium coconut husk (with and without the cation exchange) for perennial plantings. I use a different non-coconut media for annuals since the coconut stuff is hard to come by.

As far as growth rates were concerned for citrus I honestly couldn't see much difference between the two.

I'd give water rention to the coconut media, but it wasn't that big a difference.

Break down, on the other hand, under outdoors (summer) and greenhouse (winter) conditions here in Florida was very much in favor of the coconut media. I know Al thinks it will soon break down, but this has not been my experience at all. My oldest coconut media trees have been in it now for going on three years and it still does not need changing. Next year I think it probably will, but not just yet. Usually the trees outgrow their pots before the media has broken down enough to warrant changing it.

You can still overpot even with coconut media as I was once again reminded a few days ago when I downsized a Meiwa kungquat into a smaller pot from having used too large of one when I repotted it last year. If the pot size is correct though it performs admirably. It works well enough that I'll go out of my way to go to Orlando on a business hours weekday to buy the stuff.

.....Alan.