These questions often come from Florida homeowners and warrant a simple response: “Have you had a soil test done?”
No fertilization or liming should be done without a soil test to let you know what is needed in the garden. Luckily, your local University of Florida Institute of Food and Agricultural Sciences Extension office is here to help.
With tests available for pH and soil nutrients, we can help you make informed decisions before fertilizing, which saves you money, optimizes growth and plant health, and protects the environment.
Excess lawn and garden fertilization can lead to nutrients flowing into lakes, rivers and the ocean.
By knowing what your garden already has, you can ensure you are not adding to this issue by having extra nutrients flow into local waterways or into our drinking water.
Also, not fertilizing at the proper rate or timing can lead to more plant disease, insect pests and wasted money.
Testing Your Soil
You may be able to get a soil test through your local UF/IFAS Extension office, or you can send a dirt sample to the UF/IFAS Extension Soil Testing Laboratory. Check with your local extension office to understand what area options are available.
The University of Florida Extension soil testing costs $3 for pH testing and $10 for soil pH and nutrients. With both tests, you receive information on how much lime you need for your garden, but the $10 test also gives you nutrient and fertilizer recommendations.
Your local office has forms you can use with instructions on collecting and sending your sample. The forms are also available at edis.ifas.ufl.edu/publication/SS187.
A sample should be taken from an area of the yard with a specific use or plants, such as a landscape bed, vegetable garden or lawn. Take small soil samples from your selected area from 12 to 15 different spots.
Soil should be collected between 1 and 6 inches deep and mixed in a small bag. Only around half a pint of soil is needed for testing. If possible, allow this sample to dry before shipping.
There are also private laboratories in the area to consider for these tests.
Test Results: What Do They Mean?
Soil pH test results tell you how acidic or alkaline your soil is and what you need to do to correct it. Liming is the main way to correct for a low pH, but never lime without first getting your soil tested.
Soil nutrient tests tell you what is present in your soil and what should be applied to correct deficiencies. Test results help determine how you need to fertilize. Your UF/IFAS Extension office is here to help answer any questions about the tests or their results.
These tests help determine plant nutrition but cannot diagnose disease, insect issues or contaminants. They may not give a comprehensive answer as to why plants failed for the year.