I have been trying to understand and how to fertilize my trees. I’ve watched quite a few videos and saw one I’m skeptical about. It was saying if I use a 5-5-5 fertilizer and apply it at a double dose I’m applying a 10-10-10. It kind of makes sense, but would I just be wasting fertilizer or risking tree damage?
Fertilizer strength
- Thread starter Rod
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Joe Dupre'
Omono
Is this granular, dry fertilizer? In my experience, dry fertilizer is indeed more likely to cause problems. I'm a staunch Walter Pall follower and his total approach to growing bonsai. He uses mainly heavy doses of liquid, water soluble fertilizer. BUT, and it's a big BUT, you also have to water heavily. The tree will take what it needs, and the excess will be diluted and flushed out at the next watering. Some call that wasting fertilizer, but it may cost you $10.00 more per year. NO ONE knows exactly what a tree needs at every point in its life cycle, but the TREE knows. It will take what it needs and the rest is flushed away.
I’ve started following Walter also. I really like his naturalistic approach to bonsai and want to apply it to mine. This is just the start.
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Joe Dupre'
Omono
You can judge for yourself if Walter's method works. Honey locust 2 months after collection as a bare stump with no branches. 4" trunk at soil level. I had just trimmed 6" off of a few extra long branches. Double strength Miracle Gro on the 1st and the 15th of every month from March-October.
Joe Dupre'
Omono
Nera
Yamadori
I agree with Joe Dupre, if this is dry fertilizer you're only going to do more harm than any good and set the tree back. Also, as far as I know that concept of "doubling up gives you 10-10-10 from 5-5-5" has no credibility, it just means you're making the concentration that much more concentrated and the risk for hurting the roots goes up (too much at one time). Someone else can correct me if I'm wrong.
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EAlbertse
Seedling
If you have a 5:5:5 fertilizer and you double the dose you will still have a 5:5:5 fertilizer but at double the nutrient concentration. You will still have 5% N : 5% P : 5% K in that mix. If you do not follow the labels mixing instructions this could easily lead to fertilizer burn.
Nera
Yamadori
Exactly!
RoadManDenDron
Chumono
Sorry, but no.
If you use double the dose eg. Same water but twice as much fertiliser it is now 10 10 10
If you double the water also it is still 5 5 5
If you use double the dose eg. Same water but twice as much fertiliser it is now 10 10 10
If you double the water also it is still 5 5 5
Shibui
Imperial Masterpiece
Doubling 5-5-5 does not equal 10-10-10
You need to read the dilution rates. The 5-5-5 will be diluted with enough water to make it safe for the plants (say 1 gal). The 10-10-10 instructions will say to dilute with twice as much water (2 gal) to make it safe for plants. At the final dilution rate the plants ger exactly the same nutrients at exactly the same concentration.
It's in the packet and your hip pocket where the differences lie.
10-10-10 gives you a more concentrated product in it's dry form so you can store effectively twice as much in the same space. It also only used the same packaging and may be a bit cheaper to make so usually you won't pay twice the price for 10-10-10.
The reason some growers are able to flout stated concentrations is because manufacturers are conservative when they publish mixing rates. They are allowing for Stupid and for mixing errors. Printing a rate that is a bit lower than safe means less dead trees and less lawsuits.
Those who go above stated mixing limits have usually done extensive testing on less important plants to check if it is safe.
Please adhere to printed instructions when using fertiliser to be safe. If you choose to try something else please experiment first on less important plants.
bwaynef
Masterpiece
I don't have a link, but I thought I'd heard that Walter has changed a lot about his approach to fertilizer since the article where he talks about using extra-strength MG.
Joe Dupre'
Omono
As a big follower of Mr. Pall, I would like to know if he has changed his opinion of mega doses of fertilizer. All I know is I have had 10 years of stellar success with his "old" method.
Glaucus
Omono
The numbers are mass percentages where N is pure N, but P and K and the mass of the fictitious/proxy compounds P205 and K2O (P2O5 does actually exist, but it is not what is in the fertilizer). So when counting back to molar quantities or concentrations, be aware that part of the mass is oxygen.
This convention is followed in most, but not all, countries.
en.wikipedia.org
This convention is followed in most, but not all, countries.
Labeling of fertilizer - Wikipedia
EAlbertse
Seedling
I can recommend the book "Soil science for Gardeners by Robert Pavlis". In the book he explains fertilizers and also Nitrate, Nitrite and Urea, P2O5 and K2O and how to convert that to elemental P and K. It makes understanding the NPK ratios much easier. Also what is evident is that a "balanced fertilizer" is not always as balanced as we the think.
Nera
Yamadori
General gardening knowledge is an important starting point in my opinion. Get a good understanding of the basics first - soil, fertiliser, watering etc.
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