Generally I prefer slow-release/CRF for trees, be it Osmocote or Dynamite, etc, but I have found I get better growth when I fertilize - in fact maybe too much, which is maybe why my oak I posted about is so ‘floppy’ - it grew almost four feet in height last year with Osmocote as the only fertilizer.
It depends on a lot of factors. I did fertilizer my new peach and apple per recommendations I found from I believe the University of Michigan, about a month after planting and they seem to have responded. My unamended soil is very low in P so although overdoing it is possible I feel adding at least some is good - although I’m aware that it’s less critical for woody plants than for annual veggies etc.
This would be more useful to me if you’d taken the time to note the differences in approach.
One thing I know- establishing is completely different than maintaining. When establishing a small tree, shrub or vine you are a parent of a tender and vulnerable life form- the sooner you can size it up the more likely it is to survive and thrive and the sooner it can provide the crops you planted it for. Once a plant has established you probably will want to dial down the N.
Incidentally, I only use Osmocote for container trees- otherwise it seems a bit of a waste and the timed release can be detrimental. Spring is when the lions share of N is utilized by most trees. I like 90 day timed release sulfur coated urea, though. It’s relatively cheap and tends to release more early than late. The Japanese who came up with a more controlled release did a great thing, but it’s not great for everything.
Probably over 90% of the time trees will only respond to N while they are establishing. K becomes more important when you are removing it from the area by harvesting the fruit. N is the only nutrient I use in my nursery- but then, I mulch with hay, so they are getting plenty of K from that anyway. Woodchips are also loaded with K and make what’s in the soil more available to the trees as well.
i put mycrozial fungi in the hole and mix some well aged compost in the soil i put back in. mulch it well with 3in. of woodchips and watch it grow. i put 2in of compost every spring on top then remulch with more wood chips. never lost a tree this way. never used any fertilizers and growth was dark green and plentiful. i feel this way the roots are allowed to develop naturally before the tree starts to put out new growth . i used to try and fertilize with granular as soon as i saw new growth up top and sometimes killed the tree or it grew well but the growth looked terrible or stunted all together. i do use granular occasionally but mostly on my established berry bushes when im short on compost.
While visiting an old friend years ago I noticed a patch of his lawn looked markedly darker green and lush. The patch was about 12’ x 12’. When asked about this, he looked a bit sheepish and said, “I tried some home grown fertilizer in a quart jar with a dial on it that screws onto the garden hose. Did it three times early in the season.”
“What fertilizer?”
“My own urine. Took a day or two to fill it each time.”
I followed his example this spring: filled a liter jar with a dial, turned it to about 2 tablespoons per gallon and watered berries & the base of trees. Three times in as many weeks by bud break. Best crop of black currants since beginning to grow them ten years ago. Apples doing just fine. Bardsey apple had some yellowing of lowest leaves with dark spots; they dropped off and the rest of it looks grand.
I saw my brother-in-law fertilizing his plants with urine 50 years ago. I can’t remember when it became my “go to” organic fertilizer- along with compost made form kitchen scraps.
For some varieties of apples, I worry about the high K content. I think too much potassium may be causing rot spots on the apples of Honeycrisp, Jonagold, Braebern and Pink Lady in my orchard. This year I’m trying some chelated manganese after reading an article that it might be helpful.
my father used to pee around his fruit trees. never put 2 and 2 together until many years later. he never fertilized his trees otherwise but they always produced well. i collect and spread mine in my compost pile. turbocharges the process and makes great finished compost.
Why wouldn’t we have it again? Many topics come around periodically here and this one is actually pretty important to me and my approach to gardening. I can always figure out new ways to communicate this.
Scavenge and use all possible resources within your property to grow your food.
N and K are among the most important nutrients to plant growth and N is usually the only one inadequately available in the soil to produce maximum growth (besides water and air).
Maximum plant growth is what gardeners want when they are establishing plants- not just because we want them to provide food as soon as possible but also because their survival is much more assured once they are established. They also require less attention (except for the issue of protecting fruit).
Flushing such a useful material down the toilet strikes me as an immoral waste of resources (but then, I’m crazy).
If my plants could vote, they’d vote for the candidates that support recycling urine.
I remembered a line from the movie,The World’s Fastest Indian,about New Zealand motorcyclist,Burt Munro.The neighbor boy asks him why he pees on his Lemon tree?
After checking online about this,a video came up about urine as a fertilizer source.The sound quality gets very bad,a couple minutes in,but then better after a short period.bb
I stop fertilizing my trees by July but will sometimes juice them in late Sept to help them come into spring growth with greatest possible vigor by assuring optimum N is in the buds even before first growth of spring, but I have no special information that says what the ideal time is to maximize growth. For bearing trees of adequate size the idea is to feed the spur leaves but not the vegetative growth so quick release N (usually urea) just before first growth is the ticket, to feed the spur leaves but not the vegetative vertical growth. A foliar app to spur leaves after they emerge is another approach to “surgical” N application. Big fruit that tastes good comes from its early vigorous development when fruit size is increased by accelerated cellular division and not bigger cells filled with more water.
Research I have seen is that if you stop pushing growth by early summer, including letting weeds grow around trees, (which reduces nutrients including water) the affect on growth of trees is negligible, but I believe this was based on apples that slow down in the heat of summer anyway. However, I believe that spring growth is the most crucial for all the tree species I grow.
Every soil is different, and what I do in my own nursery does not necessarily apply elsewhere. Certainly with mature trees you can usually let the trees tell you what they need- I find they often don’t need supplementary N- but I’m going for optimum quality more than production at the orchards I manage.
I’ve read that some of the most productive commercial orchards supply a steady stream of nutrients through fertigation, but I don’t know when they tend to turn down the spigot, or at least stop adding fertilizer to the water.
I give some young establishing trees in my orchard a second app of 90-day N in early June after having applied it in late March- so intent am I for max growth throughout summer. I’m not concerned about them hardening off adequately because I fail to see how later fertilization would make them more tender than summer drought that comes to an end in early Sept. Not a terribly unusual occurrence that doesn’t seem to cause trees to fail to harden off at all, besides the resurgent tips of J. plums that will be killed while the rest of the tree is perfectly OK if a harsh winter follows.
I have often read warnings in the literature about the dangers of late summer fertilization leading to winter kill, what I haven’t seen is the research that backs these claims up. What does late rain after drought do that late N doesn’t? I believe that when soil that has been dry for a while suddenly gets a saturating rain, the trees get a sudden surge of nutrients, including N along with the water. Sure looks like it.
as far as i understood it. the late N fertilizations reducing hardening off and thus reduced winter hardiness (in early frosts). Was mainly for foliar applications.
I’ve regularly read advice discouraging all late summer N apps, but maybe you have seen research about late foliar apps. Love to see it if you have a link.
I bought some fertilizer for fruits, commercial, in 50 pound bags. Directions for fruit trees was to use It after tree is dormant in the fall. I have been hearing experts state this now too on numerous gardening podcasts. Which btw are excellent. The Joe Gardener Show is excellent. I loved the show on the best garden equipment. All of Joe’s shows are informative. One of many podcasts I listen to while in the garden.
If you are applying water soluble N by ground surface app there is no worse time to apply it, as I understand it, then when trees are dormant in the fall, besides when there is snow on the ground. I don’t believe trees absorb N when they are entirely dormant and your method would likely lead to leaching into waterways and groundwater. Which experts?
Wait, Lamp’l (Joe Gardener) is a well respected and qualified guru of organic growing methods. This does not make him an expert on best methods of fertilizing fruit trees, but he should be well informed on tree feralization to stimulate vigorous growth. Please provide some actual text of his advice on the subject because I don’t believe your interpretation could pertain to quick release N of any form.
Timing of ApplicationThe best timing for N application should be considered in the context of the seasonal pattern of tree N demand, that is, early season canopy development and fruit growth require large amounts of N while fruit quality development only requires baseline supply of N. We reasoned that there are two windows for regular soil N application that would fit the tree nitrogen demand pattern: one is from bud break to the beginning of rapid shoot growth and other is late in the season when soil N application no longer affects fruit quality (just before or shortly after fruit harvest). Over three years (2000 to 2002), we used 15N-labelled ammonium nitrate to determine the effect of timing of N fertilization on fertilizer N uptake and fruit N status, and found that apple trees grown under New York climate conditions were able to take up significant amount of fertilizer N between bud break and end of spur leaf growth (For details, see Cheng and Schupp, 2004). An advantage of early N application is that when it comes to harvest, fruit N status has decreased to a similarlevel found in control trees, suggesting no negative effect on fruit quality. It appears that both N applications early in the season (bud break to petal fall) and late in the season just before fruit harvest fit the seasonal pattern of tree nitrogen demand. Nitrogen applied early in the season contributes directly to the spur and shoot leaf development and fruit growth in the current season while N applied late in the fall helps to build up nitrogen reserves, which is used to support leaf development and fruit growth the following year. Considering the uncertainty of N leaching loss during the winter, early soil application of nitrogen between bud break and petal fall is probably the most practical way to meet the tree N demand early in the season. If more than 40 lbs actual N/acre is to be applied, a split application, half at a couple weeks after bud break and the other half at petal fall or shortly thereafter, is recommended. If nitrogen is provided via fertigation, application should be targeted to the high demand period from bloom to end of shoot growth.For soils that have low cation exchange capacity, such as sandy soil with low organic matter, or varieties whose fruit quality is not sensitive to N, multiple split applications during spring-summer period may be desirable.In addition to soil application, nitrogen can be applied to foliage directly during the growing season to help meet the tree nitrogen demand (Cheng, 2010). An advantage of foliar nitrogen application after shoot growth stops is that it does not stimulate shoot growth, thereby reducing the risk of diseases. So, one strategy for minimizing fire blight risk associated with rapid shoot growth is to provide just enough nitrogen to the soil in the early part of the season to achieve minimum shoot growth required for tree vigor and cropping and then use foliar nitrogen
I’m just letting people know the current trends. It’s not my method. I actually never tried it yet. And it’s slow release fertilizer that advocates fall application. Not outdated info. One of Farmer Freds ten rules of gardening is “everything you know is wrong”.
I like to keep up on what’s going on in agriculture. The topic is a hot one as we gain knowledge. Lots of discussions about it in agricultural circles. I love listening to the discussions. In the selling of trees nurseries are trying methods to sell trees all year. It’s interesting times right now. Lots of new ideas on how to do business. Anyway I suggest one googles fall tree fertilization if you wish to become informed on the subject.
I did search it and came up empty as far as any kind of N apps. during dormancy. Back it up and provide a link- if it’s slow release, why is it best to wait until the soil is too cool to release it? What slow release product are you talking about? What is the brand of fruit tree fertilizer you are talking about?
Once again, if you are going to contradict other advice on this forum provide some evidence of your claim if you want to be constructive. I love to be contradicted if I and other forum members learn something from it, but clutter isn’t useful.
I have observed with figs in dormancy in containers that the root system is active. It must be kept moist as it does use water during dormancy. Only a small amount. Apparently during dormancy trees prepare for the next season. If a tree is fertilized in the fall the roots store nutrients to be available to make sugar as soon as leaves form. The academic people are saying when fertilized in the fall fruit quality improves. That spring is too late. Again I suggest people do their own research to decide how to implement a fertilizing schedule. I myself will try this new method starting this fall. I’m not happy with spring applications anyway.
i collect and spread mine in my compost pile. turbocharges the process and makes great finished compost.
