Fall fertilizer for trees - Ask Extension
Should I fertilize. Recently planted new trees in the fall? If so, with what type of fertilizer and when should I do it? The trees were planted last ...
Knowledgebase
Fall fertilizer for trees #946672
Asked October 07, 2026, 2:09 PM EDT
Should I fertilize. Recently planted new trees in the fall? If so, with what type of fertilizer and when should I do it? The trees were planted last year up in Aitkin County.
Hennepin County Minnesota
Expert Response
Following are University of Minnesota recommendations:
- Fertilize newly planted plants every 2-3 years in the fall after the leaves have fallen or in early spring before growth begins.
- Apply it to the surface or place it in holes around the plants.
- Beware of burning turf if surface-applied.
- Water in surface applications.
- Do not apply nitrogen in late summer unless the plant is nutrient deficient, as this can promote new growth that may not harden off properly and can be damaged by winter weather.
- Apply phosphorus and potassium in the fall as they will enhance winter acclimation.
https://extension.umn.edu/garden-and-home/yard-and-garden/gardening-in-minnesota/planting-and-transplanting-trees-and-shrubs#fertilization-1401312
Experts at Iowa State University have this to say about fertilizing newly planted trees:
"It is generally not necessary to fertilize newly planted trees. Most Iowa soils can supply sufficient amounts of nutrients during establishment. If the trees grow poorly 2 to 3 years after planting, fertilization may be beneficial. Poorly growing trees often exhibit sparse foliage, yellow-green leaves, or short annual twig growth. In these situations, apply the first application of fertilizer at the beginning of the second growing season. Use a general, all-purpose fertilizer at the rate listed on the packaging."
What's said about Iowa soils also applies to Minnesota.
Learn more here:
https://yardandgarden.extension.iastate.edu/how-to/care-newly-planted-trees#fertilization
