Plant Clinic

How can I test my soil?

Taking a sample: Collecting soil for a soil test.
Taking a sample: Collecting soil for a soil test.
Oklahoma State University

Q: My plants are not doing well. How do I test my soil? Can I do it by using a kit or does it need to be done in a lab?

R.T., Miami

A: Soil testing can be done at the University of Florida in Gainesville for a nominal fee but they can only test the pH and phosphorus (which is not a concern since our soils usually have enough to meet plant’s needs) for soils from Miami-Dade County. There are no reliable soil tests for high pH soils.

With very few exceptions, the pH of Miami-Dade County soils is between 7.4 and 8.4. Because of the nature of these soils, the pH can’t be lowered. Therefore, soil testing for our county is a waste of money unless you are testing non-native soils such as vegetable garden soil that has been heavily amended. However, the pH of your vegetable garden soil will rise if you water your garden because of the high pH of our tap and well water. But your vegetables will still grow fine.

Using an over-the-counter soil testing kit is not useful for our soils either.

If you are concerned because your plants are not thriving, often it has little to do with our soils. You should contact your local UF County Extension office for advice (Broward 954-357-5270, Miami-Dade 305-248-3311, ext. 228, Monroe 305-292-4501, Palm Beach 561-233-1700) to have the plant problems identified and to get evidence-based recommendations.

Adrian Hunsberger is an entomologist/horticulturist with the UF/IFAS Miami-Dade Extension office. Write to Plant Clinic, 18710 SW 288th St., Homestead, FL 33030; e-mail

Read more Home & Garden stories from the Miami Herald

  • Washington Report

    A creative way to reach a home sale

    Interest rate buy-downs, long used by home builders, are gaining traction in the resale market.

AT HOME for release JULY 2014 BY DESIGN Caption 05: Metallics, particularly gold, continue to draw the eye in home decor. A highly polished brass four-post bed with a padded upholstered headboard is a shout-out to '70s chic. The new London collection mixes tradition and Carnaby panache with surfaces that the company calls a mash-up of golds: shiny (but warm) brass, gold-leafed woods and satiny jewel-box cabinetry. The rivet treatment on the Kent buffed-brass chest of drawers echoes nailheads on the tailored upholstered drum ottoman.


    Practitioners of ‘modern’ design are softening their traditional starkness

    For minimalists, even a whisper of decoration is like a flaw on an otherwise perfect diamond. But one reason that a more modern aesthetic currently is appealing to a broader segment of consumers is because it’s showing a softer side. That may translate to a loosening of form or color — both unabashed and subtle — where something more neutral is expected.

Crate & Barrel’s Bowery queen bed has drawers underneath for storage

    Interior design

    Need more storage? Might have to sleep on that

    Restoration Hardware’s catalogs might be getting bigger, but its furniture, if you can believe it, is shrinking. In 2012, the retailer responded to growing demand for lighter, leaner pieces by introducing a line of scaled-down furnishings. This year, its Small Spaces catalog is organized by city and residence, such as Los Angeles Bungalow or Boston Brownstone.

Miami Herald

Join the

The Miami Herald is pleased to provide this opportunity to share information, experiences and observations about what's in the news. Some of the comments may be reprinted elsewhere on the site or in the newspaper. We encourage lively, open debate on the issues of the day, and ask that you refrain from profanity, hate speech, personal comments and remarks that are off point. Thank you for taking the time to offer your thoughts.

The Miami Herald uses Facebook's commenting system. You need to log in with a Facebook account in order to comment. If you have questions about commenting with your Facebook account, click here.

Have a news tip? You can send it anonymously. Click here to send us your tip - or - consider joining the Public Insight Network and become a source for The Miami Herald and el Nuevo Herald.

Hide Comments

This affects comments on all stories.

Cancel OK

  • Marketplace

Today's Circulars

  • Quick Job Search

Enter Keyword(s) Enter City Select a State Select a Category