En EspaŅol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
rate this answer
Not Yet Rated

Friday - May 10, 2013

From: Flushing, MI
Region: Midwest
Topic: Trees
Title: Fertilizing a Mature Mountain Ash
Answered by: Anne Van Nest


What kind of fertilizer should I use on a mountain ash tree that is 25 years old (or more)?


Congratulations on having a mountain ash that has reached a good mature age. Often mountain ash (Sorbus sp.) are short lived due to insects or diseases. The Yardener.com website has a good information sheet on caring for mountain ash that has good tips. Under fertilizing they say "Mountain ashes are not heavy feeders. They can survive nicely on minimal nutrition. However, it is a good idea to feed mountain ashes in the yard once a year. In the spring sprinkle a handful or two of a fertilizer on the soil under the tree out as far as the reach of its branches (the drip line). The rain will soak it in.” They also have information about fertilizing trees.

The International Society of Arboriculture (ISA) has a good information sheet for mature tree care on their website. They offer many preventative care suggestions and discuss mulching, pruning and fertilizer application.

The Michigan State University has diagnostic services and have posted an information sheet on fertilizing trees and shrubs on their website.


From the Image Gallery

American mountain ash
Sorbus americana

American mountain ash
Sorbus americana

More Trees Questions

Problems with Texas Ash in Cibolo TX
May 14, 2010 - I have a Texas Ash tree I planted two years ago. The tree was 10 feet high with thick foliage. This spring the leaves started falling off after I spread fertilizer on my yard. The end of the branches ...
view the full question and answer

Planting fruit and nut trees in Archer, FL.
January 26, 2012 - We're looking to plant a few fruit and nut trees in Archer, Florida. We've been thinking about figs, apples, peaches, oranges, plums, and whatever nuts grow best here (looks like almonds and pecan...
view the full question and answer

Edible forest garden for northern Minnesota
March 07, 2014 - I am planning an edible forest garden for northern Minnesota. Can you suggest a list of plants that are native to this area. We are in zone 3a or 3b. Thank you!
view the full question and answer

Pros and cons of live oak leaves left on ground in Dripping Springs TX
February 20, 2013 - What are the pros or cons of leaving live oak leaves on the ground around trees or bushes?
view the full question and answer

Escarpment Black Cherry losing leaves in Austin, TX.
July 13, 2012 - Dear Mr. Plants: We live in Austin off of Mount Bonnell Road. We have beautiful 20 foot tall + black escarpment cherry tree very near the house with leaves turning yellow like it's about to drop th...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
© 2015 Lady Bird Johnson Wildflower Center