Host an Event Volunteer Join Tickets

Support the plant database you love!

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?

Share

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
5 ratings

Monday - April 21, 2008

From: Atlantic Beach, NY
Region: Northeast
Topic: Soils
Title: Plants for acid soils and coffee grounds for the soil
Answered by: Barbara Medford

QUESTION:

Please tell me what plants & flowers need acid soil and are coffee grains good to make soil acid?

ANSWER:

Once upon a time, people took their used coffee grounds outside to a shady spot and buried them. This encouraged earthworms to show up, because the grounds help to hold moisture in the dirt. Sadly, the people doing this were not doing it for the good earthworms can do for gardens, but for bait! That same principle does hold true, however, when you are preparing potting soil and need some acidity in it. Everybody knows coffee is acidic, and your stomach will remind you of that if you drink too much. So, you recycle the leftover grounds from your morning cuppa into an acid-producing, moisture-holding additive to potting soil. Plants that need an acidic soil to do well are rhododendrons (including azaleas), blueberries and blackberries, hydrangeas and many types of evergreens and conifers. Most other plants, including vegetables and fruits, need a neutral to slightly alkaline soil. Some gardeners who are growing acid-loving plants suggest using the coffee grounds as a side dressing to the plants in the ground.

 

More Soils Questions

Plants for sunny dry soil location
August 22, 2010 - Do any native plants exist in a highly sunny very dry soil location? (high overhang prevents rain but allows sun)
view the full question and answer

Problems with water oaks from Laurel MS
October 05, 2013 - The leaves on my mature water oak trees have been falling since the leaves matured. My area has had an abundance of rain this year, 11 inches above normal. All the trees in my area are doing the same....
view the full question and answer

Non-native Podocarpus macrophyllus in Ft Worth TX
November 12, 2011 - I know this question does not pertain to a native plant but I've spent too much time not finding an answer to my question. I have many mature Podocarpus macrophyllus bushes at my house I purchased in...
view the full question and answer

Yellowing leaves of Texas Sage (Cenizo) from Las Vegas NV
November 21, 2013 - Leaves of Texas Sage are turning yellow. Can you tell me why?
view the full question and answer

Plants that will grow in clay in North Carolina
March 14, 2008 - I have a small fenced back yard, predominately hard red clay, that is a major focal point. I am designing my own garden/yard area (to cut cost) and have a list of plants that will grow in this soil w...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.