Fall feeding

ripsgreentree

Well here is a subject that we should be banding about.
What are you all doing for a fall feeding scedual?
What kind of furtalizer do you prefer to use in the fall?
What are some of the dangers of a fall feeding scedual?
What are the advantages of fall feeding and what would you expect the results to be?

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ripsgreentree

It requires an open hand to give and to recieve.

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bnsaijim

RGT,

With the caveat I'm rethinking some of my feeding phhilosophies at the moment, here's my current leanings.

I feed whatever I have laying around. I tend to feed developing stock a mix of organic and chemical. Mature bonsai are pretty much on a straight organic feed at this time of year. The goal is about every two weeks but it's more like when I think of it, esp. after 3 months of TX summer which drives one into the habit of doing as little as possible outdoors.

We get a significant growth spurt in the fall and a mild winter- so unless a tree is clearly dormant I fedd year round. So I do need to ponder nutritional deficiencies even now, BUT I have grown up North so I have some knowledge up there.

Here's where opinions flare. I think this feeding frenzy is just that- botanical bovine scatology. The presence of nutrients does not promote growth- it merely sustains it. I.e. something else triggers it, like late season temperatures or some assault on the tree such as severe pruning. Try inducing your trees to comeout of dormancy in January with a good high Nitrogen feeding. Not going to happen. So why worry about it in the fall?

Also, trees are not like children faced with the Halloween candy bowl. They take up only what they need. P tends to build up in soils if it is not used. Two thoughts occur to me. If you are feeding routinely through the growth season (i.e. with the blue stuff) there is a good chance you have the nutrients present.

BUT are they available?- this is one of my fears- that the P is locked up in a salt, which may or may not make it available. This is one reason I do not rely solely on one form of fertilizer.

I think the dangers of fall (chemical) feeding is not that it will promote late growth so much that it may not get used, presenting a potentially hazardous salt build up. I think one would do well to feed the plant well during the growing season and possibly into early fall allowing plenty of "flush time" if you are using chemical fertilizers.

Next year's leaf and flower buds are pretty much developed late summer/early fall so your feeding can basically stop until new growth is pushed. Fall is not the time to make up for a lack of feeding throughout the growing season!

More critical, is adequate protection of the plant, particularly the rootball, once the dormancy process is induced. Save what you have, basically.

I'm looking forward to everyone's thoughts...

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Jim Stone
Seki Bonsai Studio
sekibonsai.com
Santa Fe, TX

Soildoc

Ok ya'll asked for it. *Here's my opinion on fall feeding. *(This stuff applies for plants and I'm guessing that tree physiology isn't that much different) (Also, I'm a soils guy and its been a long time since I've had a plant phys class so if anyone knows any differently, don't hesitate to say so). *From what I've gathered, tropicals that don't go dormant should get a balanced fertilization throughout the year. *However, you need to cut back on the nitrogen (not necessarily eliminate) in the fall. *Nitrogen does promote growth in a plant that is not dormant. *Nitrogen is a key element in photosynthesis so no N = no photosynthesis = no carbohydrates = no energy = dead tree. *The N problem is that enough must be added to maintain photosynthesis but not to encourage growth. *Since trees are quite a bit different, this will be on a case by case basis. *Add enough N to keep the tree green but limit leaf production. *Even though tropicals don't necessarily go dormant, I seem to recall that they need a "resting period" of slower growth in order to continually produce new growth every year. *This period can be brought on by shorter daylengths instead of lower temperature in the fall and winter. *That's the tropicals.

Let's go to trees that do go into a full dormancy during the cooler months. *This is where I really differ from Jim's view. *A lot of different things go into promoting growth. *Hormones, daylength, temperature, and above all soil fertility. *Try growing a plant without the 16 macro and micronutrients and see what you get (dead tree) or add N during a normal growing season and watch the results. *You'll have more growth than you know what to do with (or, on a bonsai, more than you can prune.) *The secret is to manage fertility based on the tree's needs. *During the summer, higher rates of N will promote vegetative growth while higher rates of P and K will promote reproductive growth (flowering). *Fertilization with N,P, and K later in the growing season is extremely important in preparing the tree for domancy. *During this time, as days get shorter and cooler, the plant begins storing carbs for the next growing season. *For this, N rates need to be reduced so little or no new growth occurs. *You still want enough N for photosynthesis but not so much for growth. *P and K rates need to be held constant so carb production is maintained. *Once the tree is into full dormancy, fertilization can be stopped.

All right, *by now I've probably honked some folks off so I'll quit. *If anybody wants me to, I'll talk about soil fertility and especially availability and fertilizer form (i.e. organic vs. inorganic (they both have benefits, but a plant only takes up inorganic forms).

ripsgreentree

Doc I knew that I could count on you. The problem is that even though some of us older bonsai practitioners have different methods of feeding our bonsai in the fall, many of the newer enthusiasts will not feed at all. I am hoping to see a couple of practal applications and some how to do its, before I stick my two cents worth in.

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ripsgreentree

It requires an open hand to give and to recieve.

Soildoc

Rip,

I really had intended to put in feeding stuff but I figured that I had probably honked someone off with my earlier post so I quit writing ahead of time. My fall feeding plan is to add fertilizer high in P and K and moderate in N in the fall. Usually I'll cook something up from commercial fertilizer I can get at the garden center or co-op. I'm going to try something new this fall and use the fertilizer I use on my roses through the summer. This stuff is higher in P that the standard "blue stuff" and should do OK. I don't use organic or time release fertilizer in the fall. The trees will only take up inorganic nutrients and I don't think the organic stuff has time to mineralize to inorganic before dormancy sets. What are your thoughts?

ripsgreentree

Doc we agree on the cemicle versis organics in the fall. I use a liquid called vita bloom which is 0-10-10-I will feed until growth stops or leaf drops. I generally let the plants tell me what to do. I use an inline injector so I can feed a small amount of furtalizer all of the time. This is good for me because I have such hard draning soil,only about 30% organics and no fines so water really flushes threw. This keeps a very high oxygen content in the soil that I use, also salts do not have a chance to build up. In the summer when it is 100 degrees or better you can water once a day and my plants seem to not loose rootlets. Also in the winter when it rains water does not have a chance to build up so no root rot.
I feel that it is important to feed in the fall so that your trees will have a jump on spring. It also seems to improve the servivability of repotting.

__________________
ripsgreentree

It requires an open hand to give and to recieve.

Soildoc

Rip,

The vitabloom sounds perfect. The 0-10-10 is probably a better formulation than the rose fertilizer I'm using. I need to see if I can find some around here. I generally add my fertilizer to my watering can once every week or two. I water everyday in the spring and summer until water drains out the bottom. That should keep my salt buildup pretty low. We have the high temperature problem here also. The other bonsaier here and I worked up a soil mix higher in organic matter so the soil would stay wet a little longer. This mix does make us watch our watering schedule.

bnsaijim

RGT & Soil Doc,

I at least, won't get honked off, no matter how lively the debate! I advocate a holistic view, If your own "system" of soil, fertilizer, etc. works well, then it should not be changed for the fad of the moment. Sometimes we need to agree to disagree; for awhile at least!

So, if we can at least start out with playing field leveled on that issue...

Rips, funny you should say that, I did a Club program on fertilizing (and soil interactions) and I had everyone raise their hand- same thing- Out of 40 or so people only two or three did it in the 1-2 week range, most were in the twice a year to not at all range... i.e., old guys vs. new guys, respectively, is how it panned out.

The thought occured to me that we may have a different baseline- I use an essentially inorganic (haydite) seived mix. I do use coarse pine bark for plants that need greater water retention and/or like things on the acidic side. I fertilize every two weeks or so, tailored to the individual plant or class of plant- i.e., developed, finished bonsai, etc.

What zones are you guys in - sounds like we may not be all that different- CA, MS, TX- how much "dormancy" do you get? Zone 9 and very little.

Here's my theorizing, if you aren't getting a huge drop in temperatures, have kept on organically feeding through the season, the organic will be available come spring- plenty of time to rot. Also know a few people that don't even worry about feeding after repotting just keep fertilizing... The nitrogen is short lived so not a big concern about "build up".

I've found that I can't use time release- they never seem to release- I've tried a few kinds and I'm still finding them intact in my soil and in my flower beds...

Soil Doc, how about defoliation periods as rest periods for trops?

I still don't think (excess) nutrient availability promotes growth, merely sustains it. The scenario you discussed involves a soil devoid of nutrient- which is of course, true. What of the opposite scenario- a balanced or even saturated system- will the addition of more nutrient drive greater and greater plant growth or will the excess just run out the drain hole? I get a fall growth session I want to support anyway...

So, I think my plants have a fairly regular supply of nutrients available for their asking, at least the soil should be more or less "at capacity". I wouldn't expect to see a surge of growth due to addition of N because I already deliver a steady relatively high source most of the year. UNLESS it's a finished tree- then it's seeing reduced levels because I don't want rank growth.

Know of any studies on this topic?

If you check out the Greater New Orleans Bonsai Society page Randy Bennet has an article mentioning fertlilization - he uses raw P and K on his trees- flowering ones in particular...

I guess to answer the original question- I feed well all year and don't particularly change anything late season, which seems to work well given my subjects, climate and horticulture. I use more chemical in the early spring to provide a boost on those trees needing faster growth switching over to predominantly liquid organics on finished trees as the season progresses.

I might add the following questions-

What kind of soil mix(es) are you using and do you relate the fertilizer regime to that?

And, Soil doc, since you're a "soil guy", this probably needs a new thread- What is your opinion, if any, on soil mix and mycorrhiza. A post on IBC in the last week or so has me thinking about the use of soiless mixes...

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Jim Stone
Seki Bonsai Studio
sekibonsai.com
Santa Fe, TX

Soildoc

Jim,

The soil mix I use is made up of commercial topsoil mixed with washed sand and patio/paving stone (similar to haydite). I live in zone 7 so I have to deal with a lot of heat and humidity. I found that using commercial bonsai mixes lead to watering 2 or three times a day. The sand and stone parts give me fairly good drainage while the topsoil gives just enough clay and organic matter for nutrient and water retention. I have to watch the watering schedule now since I have moved my tropicals indoors. The soil stays damp much longer and the watering habit is hard to break. My other trees still get watered about once a day but I’ll have to cut back on that soon as well.

Your theory on organic fertilizing is pretty much correct. You’ll get a “slow release” of nutrients as the soil micros break down the organic matter. This is great if you don’t have a long dormancy period.

I’ve thought about the defoliation idea as a rest period but haven’t tried it yet. I am afraid the defoliation would cause a burst of hormone activity and wind up counteracting the benefits of the rest period. I need to ask the plant phys guys about that.

As far as (excess) nutrients promoting growth, you are correct. In my first response, I assumed you were talking about the nutrients being present in “limiting” quantities. When excess nutrients are present, luxury consumption occurs. The nutrients are taken up, but stored away for later use. In this case some other growth factor becomes limiting. If your soil doesn’t have any nutrient retention capacity (clay or organic matter) then your nutrients literally go down the drain.
There are a lot of studies related to uptake kinetics (I did some of this as a graduate student) in plants and trees but I don’t know if there is anything related to bonsaied trees.

I checked out the Greater New Orleans Bonsai Society page. The P and K forms that I saw in the fertilization article are the inorganic forms I use also. I hadn’t really thought about the mycorrhiza link. Let me mull that one over for a while.