Hello, everyone. I have a question regarding nitrogen fixing by certain soil components, and how it influences fertilization. I am trying to develop a better soil for my potted maples, and have found as a component (in addition to pine bark pieces, and perlite) a mix of composted bark, wood chaff, cocofiber and cocopeat. I chose the product to avoid peat, and because it uses very little initial fertilization - it's a mix for growers, and not especially meant for the 'end user'. I talked to a couple of representatives from the firm and two growers who use that particular product. The reps in particular mentioned that I needed to take into account the nitrogen deficit that occurs with the coco products contained. This, plus the low initial fertilization seemed fine to me, since I was warned in other threads about not using much fertilization in the first place. Now since they were so adamant about this, I'd like to find out what I need to do, or worry about, if anything. I plan to fertilize these maples that are about 5-7 years old once the leaves are about 70% out, in May and only then. I am thinking about experimenting with organic fertilizers on some, non organic granular on others. Do I need to add anything when I repot now because of this issue? As I said, I was not planning to do this. If I need to add a little more nitrogen to compensate later, how much? The product has an initial low organic fertilization, like this : N 50 - 110 mg / l P 30 - 70 mg / l K 460 - 700 mg / l PH: 6-6.8 Salt: 0.4-0.8g/l Thanks for any input. schusch PS: I know these indications are in grams and liters, but since recalculating would imply me knowing how these indications are listed in North America, I thought I'd leave it as is.
what about adding mychorizae (spelling?) don't these small organisms fix nitrogen? i have bought it before from a nursery supplier. It is rather costly, but a good product. also a good organic fertilizer is Milorganite 6-2-0. It is a black, granular fertilizer. You can use it on anything.
Mycorhizzae do not fix nitrogen per se as far as I know, they do however make the root system more efficient. "Mycorrhiza can be a thousand times more efficient than root hairs at extracting minerals and moisture." quoted from : http://www.laspilitas.com/classes/mycorrih.htm another info source: http://orissagov.nic.in/e-magazine/...hizaanditssignificanceinsustainableforest.pdf
yeah, sorry, i guess they just aid in absorbing soil nutrient such as phosphorous and nitrogen, basically act as an extended root system for the plant. thanks jimmyq. but it is still great to use!
when planting in 'sterile' soilless mixes I agree that adding mycorhizzae can be beneficial, to many species of plants. In native soils it may allready be present and therefore unnecessary. If the ground has laid fallow for a length of time I would consider applying the product when planting.
schusch, I think you have a good product there with the cocofiber blend and since you have talked to some people involved in using it, I think you are on the right track. I have a couple concerns with the product as we have been considreing using it here with our maples but the supply of the product is still sparse and more of it comes packaged as cocopeat in blocks than in the shredded or chipped form. This product holds and incredible amount of moisture--I belive it is like 6x its weight if not more. In the fiber or peat form, combined with composted bark, might not be ideal. I like the small/medium (1/8-1/4" mix) fir bark mixed with the shredded from of the cocofiber, but the peat form would worry me some. Add in pumice, pumice, perlite or crushed red cinder (1-8 to 1/4"). As for the nitrogen issue, I would mix a small about of the organic granular we have been discussing in the potting mix. It has bacterial and fungal cultures that might get your mix going biologically. The composted bark will help too and be organic enough in nature to sustain things. I think the coco products actually retard fungal and bacterial growth and therefore will be somewhat of an inert moisture retaining component. There is someone in the citrus forum that uses only the coco chips in his mixes for citrus and fertilizes with dilute nitrogen with nearly, if not every watering. But that is a different plant with different needs. So, mix in 1/2 to 1/4 of the recommended dose of the orgaic fert and see what your plants do. You will be able to tell if they are struggling. If by the end of june you don't like what you see, you can supplement with a diluted liquid organic or something like 1/4 strength miracid. Then next spring, you can plan for just a bit more nitrogen in your May application or for that matter, if the mix is draining too fast and the nutrients are washing out, you may turn to a liquid organic in waterings every other week or say two different products on alternating schedules through the end of June or first week or so of July. With the age of your plants, you should have strong enough root systems to handle some moderate fertilization. But again, the cocofiber (depending on its size) maintains better air spaces than the cocopeat will. The cocopeat won't degrade as fast as regular peat, but the particle size is still comparable and I bet it will compact on you as well as hold too much water. So, make sure you use adequately sized bark and perlite or a 1/8" rock of some sort to prevent compaction. Coco products could be our savior in potted maples, but we have to be careful of what prodcuts we buy as it comes in different forms. My local nursery sells the hard chipped and dried form as garden mluch. I have a friend who grows maples who usese the shredded form and I have seen the peat form used too. Having delt with it, I will say that peat of any kind seems to be bad news for maples unless countered with adequate larger bark and inorganics. Best regards,
Thanks jimmyq, and dixie for your input. As regards mycorhizzae in potting mixes, or any type of bacterial and fungal culture, I wonder in how far these can thrive in pots - but this is for another thread - if I need to use a fungicite, like Phyton27. (I have an osakazuki that has possibly need for it.) Hello, mjh- thanks for replying. The info the company provides (the cocofiber holds little water, but aids in drainage and getting air to the roots, the peat holds water, but they claim that both have good stability, and degrade only slowly) is similar to what you are saying. They also add that cocofiber can aid in a more uniform drying and rewetting of soils that do use regular peat (this one doesn't). I intend to mix this soil half with pine bark (1/4-1 inch size range) and perlite or clay pellets in the 1/8-1/4 inch range: so 1 to 1 ratio. (I talked to a grower on the phone, who also grows japanese maples. He uses this particular mix as is.) I'll use more of a 3-1-1 mix with younger maples (3 being pine bark). I'll add the fertilizer at 1/4 or 1/2 strength when I put the mix together - this would be now, in other words, before they leaf out in late April, early May. Just to confirm: you are saying to do this now and not after leaf-out because of the nitrogen deficit or because the organic fertilizer needs time to develop in the soil? Thanks again. I'll let you know about my experiences. schusch PS: I chose this product also because of the German company, Oekohum, that makes it: I had used their products before, they seemed most dedicated and serious, topnotch customer service, good website, etc. This seemed important since I was told by a maple grower to be wary with some of the new products, and soil mixes aimed at replacing peat since the quality of material used varies, and diseases could be imported that way. The founder of this company used his observations of NorthAmerican soil mixing practices, in particular the use of bark, to develop non, or less peat based products- it is still pretty difficult to find non peat products at least in the parts of Europe that I know. I'll look out for the cocopeat compaction issue, but if I use half pine bark, perlite, etc, this could be less of an issue.
Hi Schusch, Two things you might want to look into adding to your soil mixes to replace peat moss are humus and earthworm castings. Layne
Hi, Layne- I've seen earthworm castings offered as a compost alternative. Do you use those as a topdress or do you mix them in the soil? In how far does this improve on the negative effects of peat? I am thinking in particular in relation to drainage in pots: I've read that 'compost' in general can become problematic in pots when it comes to the rapidity in which it breaks down (as opposed to pine bark, for instance) thus creating increasingly excessive moisture - a bit like peat. So may be only small amounts mixed in, together with pine bark, perlite, etc? Forgive me for being a novice in this, but what do you mean by humus - I know about the forest deposits, and that maples grow in the wild in humus rich areas, but what do we mean by humus in our artificial situations? In terms of organic sources of nitrogen I heard about 'hornshavings', meaning, I guess, from cows. Any experience with this? I intend to try various ways of fertilizing with different maples, to see which ones have good results so any input is welcome. Thanks, Layne, for any info. schusch
I suggest you read Millet's posts in the UBC Citrus forum regarding the ground Coconut husks. An easy way to read these posts is just open up the Citrus forum, click the Search this Forum, which is located to the left of the Subscribe to Citrus's RSS Feed icon and then from the drop down menu, type in CHC and then click the Go icon. I think that if we are looking into improving our container soils for Maples that we have some idea as to what we want to accomplish. As far as using the ground Coconut Husk Chips and what percentage of them we will use in our soil mixes, I think we need to keep in mind how we want to water our Maples such as are we planning to use hose watering or temporary irrigation such as drip emitters or do we plan to use a form of permanent irrigation such as sprinkler irrigation. I would think the type of irrigation we want to employ will help determine for us the amount of CHC we will want to add to our predominately ground Forest Humus and perlite soil mixes for container plants. Even when people are cautioned that heavy applications of Nitrogen and Maples do not get along well together, some people still are thinking about using Nitrogen as their main nutrient component additive. From my own experience there are other nutrients applied in small quantities that are just as important for us. In some cases more important than Nitrogen will be for Maples for the long term but people insist on wanting to have these plants grow fast and furious and have lush "green growth" when young and that is okay up to a point as when certain diseases hit and then all of our efforts to improve the plant to make us feel good can go by the wayside as even though we felt we were seeing a stronger plant right before our eyes, we in fact weakened the one component we will need to help us overcome Tight Bark and Verticillium in the plant issues later and that is the roots. Low level Nitrogen applications are much less harmful to the roots than heavy doses or high concentration doses will be. Even with "juiced" rootstocks, those that have been inoculated with mycorrhizal fungi are more likely to cause us trouble later as in order for the fungi to be a benefit for us we have to ensure there are plenty of nutrients in our soil for us to see the results of the fungi in our top growth. In order to sustain the viability of the fungi to help us we probably will have to supplement nutrients in our soil mediums to help it along as we want better top growth so later on we may have stronger root systems. The problem arises with mycorrhizal fungi in warm and especially cool climates is that in warm climates the fungi die out rather fast and the fungi do not like salts in the soil at all. In cool and wet climates the fungi that has both entered and covered the root hairs can act as a harboring agent for a root rot fungus to use as a medium to grow on. There is a real fine line in our use of mycorrhizal fungi as we can get a benefit from it that we can see in warm but not hot to cool but not cold climates but we also can have a ready made hindrance to the plant that we helped create. Once the juiced rootstocks are in the ground the fungi tend to die out fast in many growing areas. The whole purpose of the fungi is to live in symbiosis with the plant but the life cycle of the fungi is not for a long period of time. People using the juiced rootstocks feel that with the root system able to perform more efficiently at absorbing nutrients and helping water absorption that the presence of the fungi will help heal graft unions faster which will give invading organisms less chance to come in and infect right at the wound. In this sense their thinking is probably correct but once the graft is healed then we go in and want to supplement the nutrients in the soil so that we can see a better plant and in many cases we end up killing the short term beneficial fungi in the process. Small doses of fertilizer and more than likely liquid applications will be less likely to kill off the fungi as many of our granular fertilizers contain salts and chlorine in them which the fungi will not like at all. For the long term we may not see the benefit of the fungi but for the short term we can give the plant an added boost when young that can help the plant later and later on down road that perhaps may be a benefit for us then. I kind of confused the issue a little as mycorrhizal fungi may be better thought for the short term rather than for the long term is how I look at it. If we really want juiced rootstocks to work for us we will still need to have disease free (clean) and preferably vigorous rootstocks for us to get the ultimate benefit or we just end up spinning our wheels looking for a quick fix solution for the short term and still not deal with the long term threat to our Maples that will eventually kill them. Jim
Hello mr shep- thanks for pointing me to 'CHC' in the citrus forum (I had entered 'coco' in the search engine and hadn't found anything after mjh mentioned it). Compared to pine bark coconut husks seems to have the advantage of retaining moisture while improving aeration as well - as millet in that forum explains. Could one use 1/4-1/2 inch husks instead of pine bark chips in soils for maples, or are they meant to be used instead of peat because of their moisture retention capability? If at all possible, could you say a few words in general about the difference of hose versus drip or sprinkler irrigation and soil composition in pots? (I am thinking about using some kind of irrigation system for my maples planted in the soil, not in the pots.) I took your warnings regarding nitrogen very much to heart - here my question originated from the nitrogen fixing apparently caused by the coco and what to do with maples 5 years or older in relation to that - does nitrogen fixing affect the soil situation in any way that should be a concern: do we adjust or do we continue to keep nitrogen as low as possible? The product that I mention, and that was discussed with mjh, was an organic formula by Foxfarm, with a granular 4-8-5+8%calcium+some magnesium+organically derived micronutrients that they say they designed with japanese maples in mind. In any case low-level application - as mjh suugests - it will be. (I have repotted a number of my younger maples and will not fertilize just to confirm that your recommendations weren't lost on me.) The product also adds mycorrhizae+humic acid - you are mentioning the pros and cons of inoculating rootstock with mycorrhizae, which would be different from adding to or encouraging them in the soil, if I understand correctly? Unless I misunderstood and what you write applies to any type of mycorrhizal application, do you see any benefit in adding them to container soils, like this formula does? As regards adverse side effects, in my case the danger would be a possible rained-out summer (and less an overly hot one) and thus root rot that you say can be encouraged by the fungi, as well.
Hi Schusch, Sorry for the delayed reply. I wanted to show a pic of the consistency of the soil I am currently using. Before I was using Whitney Farms Cactus mix with good results. It has a mixture of aged Fir bark, peat, composted steer manure, sharp sand and pumice. It has excellent drainage and moisture rentention. The only thing I didn't care for much was the peat. Peat as you know need a lot of water to get it wet, and once wet stays pretty wet. For cacti this is fine as you allow the soil to go completely dry before the next watering in a week or so. Peat is also fine for plants needing more wet condtions like Colocasia (Taro). This is not ideal for maples. I was going to repot a maple recently and went to get more of the Whitney Farms Cactus mix. When I got to my local garden center I found they had completely switched out their inventory and no longer carried the cactus mix I liked. So, I began looking through what they had and didn't like what I saw until I came across Sun Gro Horticulture's Black Gold cactus mix. It is a combination of forrest humus, earthworm castings, fir bark and pumice. The "pumice" is somewhat of a misnomer in that it's really crushed red cinder/lava rock and not the typical white pumice you normally find in potting mixes. While both types of pumice are good I personally find the cinder/lava rock preferable. I believe the finer, sharp edges of the cinder promotes the growth of finer feeder roots. I've literally been on a quest to find this type of cinder/lava rock in stores or online, either the black type or red type. Most of the stuff I find are for decorative use as a top dress and too big for use as a potting medium. But the stuff in the Black Gold is just about right at 1/8" to 1/4". This product is only available in the USA western states. I've included a couple pictures below so you can at least see the consistency of it and maybe you could duplicate it. I've been reading (and listening) a lot about humus, humic acid, and earthworm castings for the past couple of years, but haven't really put any of it to practical use until now. I've included a couple links for you, but you can do a google search to learn more. http://en.wikipedia.org/wiki/Humus http://www.ar.wroc.pl/~weber/typy2.htm If you do a google on earthworm castings you'll find a lot of info. In terms of how it compares to peat or regular compost I'd say it's better. One of the nice things is that hopefully your castings will contain earthworm eggs that will, when they hatch, help aerate and condition the soil as they move around inside the pot eating whatever organic scraps you put on top. I've only started using this mix and though I usually hold back talking about a certain product till I've had a chance to use it for a year or two, I think the Black Gold cactus mix is very good for potted maples. I've been reading a lot of good things regarding coco peat/fiber (not to be confused with cocoa peat), but haven't used it in any of my potting mix. Reasons are it's relatively expensive and hard to find locally. I am planning to do some air layering this year and am looking into using it as a soiless rooting medium. I'll leave with saying don't be too fixated on nitrogen fixation of the soil for maples. Unlike my Kishu mandarin tree the maples sip nitro and don't need much to look good and stay healthy.
Thanks, Layne, for the extensive reply. The pics are interesting: the mix resembles (visually) what I am putting together, so it strikes me as good that it is available as is, since all the commercially available mixes I have encountered seem problematic from the breakdown/aeration point of view. Earthworm castings, etc, are intriguing, already as an idea. Do you repot every year, though - meaning do you need to worry about breakdown of the components after one year if you use certain organic material? On the other side of your approach in terms of investing in alternative organic material would be someone who uses all non organic components (different kinds of grit, perlite, etc + bark, in the 1/4 -1/2 inch or more range - which I have seen recommended for root development. The drawback being the need to water daily in the summer. Thanks for the info, the links and the pics. schusch As regards nitrogen fixation -which is the subject of this thread - I chose the mix the company offered because they didn't add any 'biocompost', which implies a higher initial salt content, as most 'alternative' mixes in Europe seeking to replace peat products still do. Then the reps started asking me repeatedly about the nitrogen situation, and what I intended to do, referred me to one grower to discuss with him his fertilization regiment for maples, as if it was really an important concern that I had to ask a question I thought I had solved in my mind, which is to fertilize very little. In other words, what I gather from you and the others, the fixation is not a real problem since maples do not need that much nitrogen.
Hi Schusch, With regard to repotting I don't do it every year. Maybe once every 2 or 3 years. I'm less concerned with organic breakdown than with root constriction. I will either repot into the next larger size container if I want the tree to gain more in size or root *and* top prune to keep the tree the same size and in the same container. I think what you have to keep in mind is that the breakdown of organic matter is a natural occurance and is a good thing for the plant. The problem is addng too much [fresh] organic matter to the potting mix. I know you understand this. By adding inorganic soil (pumice, cinder/lava rock, perlite, etc.) to the potting mix we sustain good drainage and aeration till the next repotting. Even after a couple years the mix I've been using and the *original* soil that came in the pots still have good drainage and aeration. I credit the grower with providing the maples with good soil. In answer to your second paragraph I've included some links that might be of interest regarding non-organic potting mediums. Two things of interest are that bonsaists typically use what is at hand locally and their mixtures are typically lean in organic materials. With regard to more frequent watering you are right. Being planted in unglazed ceramic pots it's typical of bonsaists to water once or twice a day. The first link shows the type of cinder I've been looking for locally. I was thinking of buying from these guys, knowing that shipping a 20 or 25 lb. bag of cinder would probably cost almost as much or more than the product costs. This is the type of stuff I would help my dad dig up along side a highway in Hawaii when I was a kid. We'd take it home and sift the dirt through homemade sieves to separate out the finer particles. The 2nd link is bonsaists chiming in with their personal soil recipes. The "Turface" that's referenced in the second link is a manufactured fired clay that was orginally intended for baseball infields. Because the clay is fired at very high temperatures it doesn't break down as quickly. Akadama is one of the things they use in Japan. It's naturally occuring and very similar to Turface. http://www.trappist.net/estore/merc...Code=BM&Product_Code=LR-20&Category_Code=soil http://www.bonsaisite.com/survey5.html http://www.dallasbonsai.com/store/akadama.html Hope this helps, Layne
Hi Layne- thanks for the replies. I had already looked into what bonsaists do, as understanding water movements in pots is crucial for them. Watering every day becomes not practical for me, since I need to rely on others during the week - having said that I would like to see for myself, and know whether these type of inorganic soils (very high drainage and aeration) produce better root development and healthier maples - as regards diseases, etc. At the same time I wonder about any problems stemming from drying out so quickly for regular sized trees. Schusch
Hi Schusch, If you want to use a higher ratio of inorganic potting medium to organics and watering every day isn't practical and relying on others is "iffy" (I know the feeling...my grandfather who was a cabinetmaker was great at working with dead trees, but not at keeping them alive) perhaps you should look into an automatic micro-irrigation system. They're relatively inexpensive and simple to set up...if you have a few plants. If you have a lot of plants more planning is involved. With regards to a better root system bonsaists believe, and I can attest to this, that the sharp type of cinder/lava rock helps promote more feeder roots. When you repot a tree that has been growing in this type of medium you will see all the fine roots clinging to the cinder. You can not wash or shake the cinder off. This is because of all the tiny roots finding their way into the nooks and crannies...nooks and crannies that retain moisture and nutrients. "At the same time I wonder about any problems stemming from drying out so quickly for regular sized trees." I don't quite understand you on this one. Do you mean larger container trees or trees in the ground? If you're referring to larger containers...say 5 gal. (19 liters) and up it's been my observation that larger containers dry out slower than smaller containers even though they contain larger plants. So, if you were to plant a large tree in a large container with a mix that had a higher ratio of inorganic to organice mix it won't dry out as quickly as a smaller containerized tree in the same mix...if that's what you're asking. Layne
Hi Layne, I have been thinking about an automatic watering system for maples. I guess there are different types. Any recommendations? My question about larger trees in pots wasn't well put. Let me try again: as regards recommendations for soil mixes, a lot of people here on this forum and elsewhere in North America insist on good drainage/aeration as most important and this makes sense, and I have applied these recommendations. When I discuss ratio, meaning adding pine, etc to my mixes with a few growers here in Europe, they seem to start worrying that with more than half of the mix being pine, perlite, lava rock, etc that the maples do not stay cool enough in the summer. My thought was: I just need to give enough water at the right time, but I couldn't figure out why they give me a questioning response. Different practices, less experience with pine, may be? The other side of the question wasn't spelled out: I had read a couple of times that the roots of larger trees in larger pots need the right soil consistency to steady themselves - with lighter soils not providing a firm enough roothold. Plus if I had to move these trees from the pots to the garden soil in the ground the trees with the lighter mix would have a harder time to adapt than had I used a heavier mix. By lighter I mean soils with very little or no loam in them, and with lots of draining material added. (In any case I have repotted the larger maples into a much lighter mix, and we'll see. I have some older, larger maples in 20+ gallon pots and after a year the roots had already invaded most of the space, so a lighter mix should also help me repot in a couple of years.)
Hi Schusch, As for auto watering systems you might be able to find something like this in your area. Look at the micro spray jets and the adjustable sprayer assemblies, either the adjustable or non adjustable types. These are what some nurseries use. http://www.raindrip.com/ http://www.dripdepot.com/cgi-bin/drip/spray_jets.html?id=fbQFbuFh http://www.dripworksusa.com/store/sprayer.html You just hook this up to an auto water timer. Make sure you have an anti-siphon fitting so the irrigation water doesn't back up into your drinking water supply and contaminate it. And make sure that it is at least 6 inches above the highest point in the line. You might also need a pressure regulator. With regards to using more inorganics in the potting mix a good ratio starting point would be about 1 part inorganic (pumice, cinder, sand, etc.) to about 2 parts organic. You can certainly play around with the ratio given your specific location either increasing the inorganic medium or decreasing it depending on your aims. As you saw with the bonsai poll there are a lot of ways to do it and there is no real wrong way. If you are concerned about the tree not having a good foothold when they get larger you could make the mix heavier, but I don't necessarily think it would be too much of a problem with a lighter mix, especially if they are in containers. You'd be surprised just how strongly roots can grab onto things to give the plant a good foothold. In nature you'll see trees growing in very rocky environments. Bonsaists will even duplicate this in miniature by doing rock plantings. They'll use plants that lend themselves to this type of technique ie, plants with fiberous root systems. In fact my father's late bonsai teacher had a small ficus literally growing on a rock in the middle of his koi pond Keep in mind too that inorganics such as pumice, perlite and cinder retain moisture too as their structure is porous. The only one that doesn't retain moisture is sand. And while it's a fine potting medium you have to be careful not to use too much sand. You'll get good drainage, but not enough moisture/nutrient retention. Hope this helps, Layne
Thanks. Layne, for the info and the links. I heard about the drip systems providing the right kind of moisture. So I'll definitely look into it. Thanks again for all the input. schusch
