Mistake number one is to give the maple large amounts of nitrogen in the first and second years. A small amount of organic slow-release fertilizer in the spring would be much better for your plants. I have had really good success fertilizing in late April with Fox Farm Japanese Maple fertilizer 4-8-5 and Dr. Earth 5-5-5. Is the tree looking sickly? Would you like it to grow more quickly? Or are you just trying to give it the best care that you can?
Japanese maples are truly one of. If you want to learn when and how to fertilize a Japanese maple tree, this. And color to your garden that you’ll want to take top care of the tree. Tip 2 Fertilizing your Japanese maple with the proper type of fertilizer should be done either in late winter while the ground is still cold (frozen?), or after the last freeze in spring. I recommend using a slow or controlled release type fertilizer. A general guideline to use for mature Japanese maple trees is 1/10 pound of nitrogen for every 1 inch of tree trunk diameter measured at 4 1/2 feet from the ground.
If you fertilize other plants in the Japanese maple trees’ area at the same time, use the guideline of 1/10 pound of nitrogen per 100 square feet. Get feeding and watering tips for Japanese maples from the experts at Wilson Bros Gardens. Note: Do not fertilize a Japanese maple at planting time. Please Note: If you are growing a Japanese Maple follow these links for care. Though not absolutely necessary to do, before fertilizing your maple tree the best.