Before getting into this sample your soil and have it tested, Oklahoma Cooperative Extension can probably help with soil testing.

I have heard some concerns about chlorine and the use of Miracle Gro. Applications of granular fertilizer to the soil surface is a better way to go anyway.

If soil test report indicates a need for fertilizer, follow application directions on the product label. Choose a product that supplies what soil test report calls for. Do not apply a bunch of nutrients appearing to be already present in your soil in adequate amounts.

Japanese Maples are sensitive to salts in the soil, and most commercial fertilizers contain nitrogen and other components as salts. Its better to use fish emulsion or a low-nitrogen organic fertilizer ONCE in the spring after bud break. Unless your soil is extremely poor, they don't need a lot of fertilizer - especially excessive ammounts of commercial fertilizer. I use Plant-Tone organic, which also contains 15 beneficial soil microbes that will help your tree absorb nutrients better and stay disease-free.

Regards,

K4

Bill,

If you plants are in the ground (not in pots) make sure that the trees have no competition from weeds and grass and keep them mulched.

If you're inclined to be more thorough having the soil tested and determining action based on science is good gardening. Competition and weed free along w mulch still a good practice.

billpilot88,

Rule of thumb, if you want to fertilize, apply 3 weeks (+/-) after budbreak and fertilize only once, maybe twice...really depends on the length of your growing season. Last application should be about 3+ months before historical first frost date (this will give your plants enough time to harden off/toughen up). Once they are really established, they dont need much.

Schmoo

Forgot a few words..."fertilize only once, maybe twice with a granular" (10-10-10,14-14-14,15-15-15,16-16-16)

Schmoo

Do NOT.
I repeat... Do NOT fertilize trees with miracle gro.

"Do NOT fertilize trees with miracle gro"

I would be interested in "why not". I agree with bboy, granular is the most efficient way of suppling some nutrition (lasts normally quite a bit longer than fertilizer already in a solution), but it is all salt to the plant. Why not???

Schmoo

The sheer number of complaints about dead trees after using it.

Fine for vegetables but to use on an expensive JM is really a bad idea.

Regarding the suggestion to apply ferts 3 weeks +/- bud break I believe that would be incorrect advice for a zone7 garden. I think the soil is too cold at this time, there would be very little nutrient uptake. Many of the chemicals would just leach out with rainfall.

Also regarding using various formulations eg 10-10-10, 14-10-8 etc it would be a mistake to apply either granules or soluble salts without knowing the chemistry of your soil. You could be creating imbalances as easily as correcting them.

"Regarding the suggestion to apply ferts 3 weeks +/- bud break I believe that would be incorrect advice for a zone7"

This comment is based on research work in Oregon showing after bud break, the first 3-4 weeks of growth is promoted by stored nutrients. Once those nutrients are used up, the plant (deciduous trees were the trial plants) will actively take up nutrients. While Oregon is different from Oklahoma, I wouldn't think the trees nutrient uptake "patterns" would vary because of the state/zone it is in.

"You could be creating imbalances"

So if billpilot88 applies a labeled rate of 16-16-16 to his maples, without a soil analysis...what imbalance could he create???

Schmoo

Schmoo,

The stored nutrients are from the previous fall. Autumn fertilizing is supported by science.

The imbalance would be created, for example, if the soil was already rich in phosphorous. If you applied a 'complete fertilizer' making phosphorous over abundant this would suppress plant growth by making micro nutrients unavailable.

Here is Whitcomb, Establishment and Maintenance of Landscape Plants pg. 452 "The widespread practice of applying 10-20-10 or 10-10-5 or similar "complete" analysis fertilizer, without the aid of a soil test to see what is needed, is asking for problems."

on pg 454 "The best time to fertilize most existing woody landscape plants is in the fall." He discusses how wet, cold, poorly aerated spring soil will not support optimal nutrient uptake.

I was told by an arborist to fertilize my jap. maples in the fall. He did not mention a soil test to me at the time but this makes alot of sense to me.

I would just use organic fertilizer. Fall fertilizing is number one. Spring fertilizing is number 2. Both together would yield greatest benefits. For new trees, I prefer to use hydrolyzed fish oil. Works right away in the root zone. For established trees, alfalfa pellets and soybean meal will work.

Here's pictures of my shantung maples that I grew since 2006..

What they grow in... limestone rubbles...

{{gwi:79083}}

herman neutics,
"The stored nutrients are from the previous fall. Autumn fertilizing is supported by science"

Yes, nutrient storage and its use by trees for spring growth is a known fact. While information on the benefits of fall fertilization are supported by science, it you actually look into it you will find spring fertilization is also supported by science.
While I respect Dr. Whitcomb a great deal..he has been there and done that for many, many years...but if you think he is the only knowledgeable scientist/researcher person out there studying & publishing...are you operating via sound science??

Schmoo

Whitcomb is a trailblazer. But I don't see referring to his findings in a post here as a statement that only his work is valid.

Ya Schmoo,

Clearly there are lots of 'scientific experts'. I just learned about Whitcomb so I used a book that was close by.

The suggestion raised that I'd quarrel with is the feeding 3 weeks before budbreak in zone 7. I'm in zone 7 and 3 weeks before budbreak the gound is definitely frosty if not frozen. Seriously think it's a good idea to apply chem ferts to 30-40degree soil? I definitely disagree with that practice in a zone 7 garden.

If you were suggesting fertilizing with organic materials I'd agree with that. Putting down compost, manure other organic material in early spring or late winter is a good idea in my book too.