According to this PDF document[super]*[/super], it is a myth that phosphate fertilizer stimulates root growth upon transplanting. It is written in the context of field culture but I expect the findings would also apply to indoor container culture. If a high phosphorus fertilizer is to be avoided, should one apply a fertilizer appropriate to the plant but at half-strength instead? Also, are high phosphorus 'transplant' fertilizers to be regarded as snake oil? * Thanks to Daniel for the link to the list of horticultural myths posted in another thread.
Actually, it might be a myth that the application of any fertilizer will promote root growth upon transplanting. Adding in certain plant hormones might be another matter. Applying ammonium nitrate at transplanting time can be more injurious to a root system than the additional phosphorous can be. Why use a fertilizer when we transplant anyway? Wait for the plant to settle in and then add in fertilizer later if desired. What we want to do is protect the root system during a transplanting, not immediately trigger the plant into producing shoot growth at the expense of killing off some off root system. I would not add in any fertilizer at all with NPK during or immediately after a transplant. I'd wait until the plant showed signs it has started to adapt to its new planting site or new container before I would even contemplate fertilizing the plant with any nitrogen, phosphorous and potassium. I might not feel the same way about adding in minute quantities of manganese, zinc, iron, calcium and sulfur but only in a liquid form soon after the transplant. Under what conditions and which plants were transplanted that did not show any signs of new root growth with the addition of phosphorous and what quantity of phosphorous was applied in actual field studies? Was the phosphorous applied sans other macro-nutrients? I am not arguing the basic over usage of phosphorous as I know that is more than true in the Mid-West and to some extent here as well with various production crops but plenty of crops not widely grown in Pullman do respond to applications of fertilizers having some phosphorous in the formulation in conjunction with other nutrients. These fertilizers are not applied solely as a standalone phosphate fertilizer like a single superphosphate will be used around here for Alfalfa, Vetch and dry land Clovers among others but then again these are agronomic crops, not trees and shrubs. So I guess the recommendation out of Pullman is do not use phosphorous on production Apples in the state of Washington as there is already enough residual phosphorous in the soil to preclude any additional applications of fertilizers containing phosphorous in them. That may be okay for Washington but will not be recommended here for our production Fruit & Nut Trees. Jim
FWIW. a certain tree guru said to a group this Summer, " you can't feed a plant "which drew a few oohs and aahs, he then qualified it by saying "a plant manufactures its food through photosynthesis" which Google defines as "The process by which green plants make carbohydrates such as sugar, using water, carbon dioxide, and sunlight". no mention of "plant foods or fertilizers" as such. I need to see more intelligence on this subject as I am unsure what these observations and definitions really mean when it comes to plant growth.
Would this apply to an indoor potting mix? These mixes are typically a combination of peat, perlite, and sand without any fertilizer charge. Wouldn't this be a medium almost devoid of nutrients to start and thus would require an initial boost?
I would tend to agree with Jim (Mr Shep) that the best thing to do is to let the plant settle into the new environment. If we are using "Native Soils") i.e. not bringing in "new" soil from a garden centre or another place that has no relation to out own garden) we should be restoring the fungal and biological entities back into that area. Then the old addage "Feed the soil not the plant" will work. In most areas where there has been extensive cropping or urbanization ther is little need to add more phosphate into "our little patch". I acknowledge there may be a need in certain areas where 'production' is occurring but it seems that most people and retailers are in the mind set that bone meal is all you need. Time, patience and good preparation of the soil will do you better than a handful of bone meal. I have had good success using native soil and a liquid transplanter with a root hormone added to it. the theory is the root hormone will act like an anti septic and being in a liquid form the plant and the soil will absorb as much as it can use at any one time. It may just be a placebo effect for us humans!! Pierrot
Would this apply to an indoor potting mix? These mixes are typically a combination of peat, perlite, and sand without any fertilizer charge. Wouldn't this be a medium almost devoid of nutrients to start and thus would require an initial boost? I did not want to come back into this thread just yet as I am a little uptight about something, so bear with me. Indoor potting mixes still have some humus (either ground fir, pine or redwood) in them. When the humus breaks down, the decomposition of a solid into a liquid form will enable the roots have some nutrients to utilize. That was in effect one of the rationale for not adding a fertilizer form of phosphorous to the soil medium as we will get some phosphorous from the potting soil at some point in time but the summation (bottom line in the .pdf file ) had nothing to do with the actions or interaction of a phosphate fertilizer upon an actual transplant. Some people forgot or never knew that phosphorous by itself does not help generate new root growth but instead helps maintain the old roots and helps strengthens the new (more recent) root growth. I am not into boosting. I am into protecting what I've got for a root system. I developed my own line of a cereal crop as well as a field crop just to disprove what I was taught for many years that in order to produce a decent field crop I needed 400 pounds of nitrogen, 300 pounds of phosphorous and 350 pounds of potassium per acre. I felt I could cut those amounts in less than half and be successful at it and I've been doing that for 27 years now. We do not need that much fertilizer to be applied just to produce a good crop as much of it is simply wasted and I proved it to me that I could do just fine doing things my way and I have. By the way I do my own soil testing and soil analysis so I know what I need or want for nutrients before I ever fertilize either of those two crops. I have not seen phosphorous toxicity per say down here but when we apply that much phosphorous year in and year out, as mentioned above, just on that one crop I would think I am in a better location to see what excess P205 can do to a plant than most people will. In the Mid- West on corn, too much but also not enough phosphorous can yield what some people may think is the old virus yellows condition as we called it. Some people simply call it yellows (corn yellows, yellows of corn) for short. Jim
The first step to finding out about nutrients in a soil/medium is to sample it and have it tested. Don't fertilize blindly! Withholding fertilizer from a plant that needs it is also counterproductive. Recent handling (planting, transplanting) does not automatically preclude a need for fertilizer.
When someone writes of using ammonium nitrate as a supplement for transplanting it should not be used as a generalization. The use of a double form of nitrogen should be specific in which plants can tolerate the nitrogen and which plants cannot at time of transplant. Also, age of the plant being transplanted also is a concern. When we bump up a one gallon sized plant to a five gallon we are in effect giving the plant a boost just with the new soil. We can work wonders at times just by giving the plant new soil. The one area that most of us fail our plants is that we leave the plants in containers too long without adding in new soil periodically. We have to allow and think in terms that the soil will break down on us and for container Japanese Maples the reason why the plants falter after about 10 years in a container is that we have not replenished the soil medium for the plant to grow in. Many times when a Lemon starts to have its leaves turn yellow we do not have to automatically fertilize the plant. We can give the Lemon new soil and wait for a little while before we give the tree some added nutrients to help for the signs of chlorosis. This is not rocket science, when we can see the plant is not happy we do something for it. Many times all we need to do as a quick supplement is give the plant new soil and later after the plant has had time to adjust then we can go in and fertilize it if we want. The key element for most plants but not the leguminous types that can fixate atmospheric nitrogen on their own and store nitrogen in their root nodules is that we apply phosphorous in conjunction with other nutrients, not as a standalone phosphate fertilizer. What is written in the .pdf file is accurate for usage of phosphorous by itself but doing that is not and has not been recommended for many years. Some of the reasons why were indeed pointed out in the file. The initial question dealt with transplanting in how phosphate fertilizers have not shown to produce root growth. Applied by itself phosphorous can be harmful rather than be beneficial to a root system. When we also add in calcium, potassium, sulfur and a small quantity of iron then the phosphorus in the root system can work for us to help strengthen the roots, not force or enable the plant to produce new roots. The latter part is the myth but I am not sure that "phosphate fertilizer" should have been referenced in the .pdf file as no one really is applying phosphate fertilizers much any more as a standalone. In labs people have used phosphate fertilizers for plants grown in test tubes and in culture and depending on where the plant is in its development then a small amount of ammonium nitrate may indeed be more helpful as a boost in cellular grown plants but in actual field studies I am not so sure that ammonium nitrate can be much better for us but we also need to qualify which plants will it be used on and are these plants to be transplanted into the ground or bumped up to a larger container. For container plants, I would never use ammonium nitrate by itself or a single or triple superphosphate at transplanting time. I would be hesitant to use the latter at any time for container grown plants. Thanks Ron, I was not trying to be rambunctious or off the wall. I've been an advocate of using less fertilizers for many years. To me the timing to apply a fertilizer is more important than how much fertilizer we apply. I'd rather apply smaller amounts when I feel the plant can use it rather than to automatically apply "x" amount of pounds or ounces all because someone else suggested I do so. Jim
Dear Ron and Mr. Shep, I am really intrigued by this whole concept of how plants take up, make use of and react to soil nutrients. Having been involved with installations lately, I'm finding I'm prone to mixing in light amounts of a 4-2-2 organic meal fert and allowing the surrounding soil to enliven itself. I think of it as a "buffet for the wee beasties" needed to start a microbe chain. 'Feed the soil' actually works. Certainly pouring chemicals in doesn't. I know because when I started planting my back yard slope out here in the woods, I had to chip away at the mountain 'soil' consisting of an inch of duff, rocks the size of oranges and fine silt. I tried lugging buckets of earth up the hill. I quit really soon. It just didn't help.I swore the more I'd topdress the more it sunk into the mountain. Then when the soil feeding concept came along, I began with this organic fert from the feed store, sprinkled it twice a year for sure, cause it was easy to lug up the slope. OK ,OK, - so I added half composted leaves one fall - cause they were in the way, some lousy topsoil once, and a couple of really skimpy dressings of bark mulch. I did actually sprinkle the organic fert though. 4 years in total I've been at that mountain side slope . Except by golly if the last couple of times I went up to dig a hole, wasn't there just the most lovely worm laden earth? For like a foot or so deep.- And in several places! I guess I got something going good. Struck a balance maybe. Some fine wee beasties have sure made this their home, and I'm very grateful. Now I have a question for you..... What do you know about " willow water" as in the cuttings from salix infused into water as a natural hormone for rooting. I know of several old timers who swear by it. Anything on the mythbusters? Anne
Sap collected from a freshly cut Willow stem mixed in with rooting hormone and a talc or paste made from the mixture used as a "quick dip" can indeed facilitate rooting in a variety of plants. In the sap is an acid, pretty much the same acid that is the active ingredient in aspirin. I am not going to go into the concentration we used but it sure helped with some of the tougher plants to root from cuttings. Jim
