soil test

Soil Testing Lab is Open

soil in hand

In light of agriculture (including community gardening) being designated as essential, the UConn Soil Nutrient Analysis Laboratory will remain open utilizing best practices; social distancing and disinfecting are a high priority. No one will be allowed in the lab but essential personnel. Any soil tests need to be mailed or left in the drop box outside the lab. Anyone needing a soil test should go to Tests will take longer because they are running on essential lab personnel only.

Have Your Soil Tested for Macro and Micro Nutrients

person holding a cup of soil
Photo: Dawn Pettinelli

Send your soil sample in for testing now. Our standard nutrient analysis includes pH, macro- and micro nutrients, a lead scan and as long as we know what you are growing, the results will contain limestone and fertilizer recommendations. The cost is $12/sample. You are welcome to come to the lab with your ‘one cup of soil’ but most people are content to simply place their sample in a zippered bag and mail it in. For details on submitting a sample, go to UConn Soil and Nutrient Laboratory.

Have your Soil Tested for Macro & Micro Nutrients

cup of soil being held in Soil Nutrient analysis lab at UConn

Send your soil sample in for testing now. Our standard nutrient analysis includes pH, macro- and micro nutrients, a lead scan and as long as we know what you are growing, the results will contain limestone and fertilizer recommendations. The cost is $12/sample. You are welcome to come to the lab with your ‘one cup of soil’ but most people are content to simply place their sample in a zippered bag and mail it in. For details on submitting a sample, go to UConn Soil and Nutrient Laboratory.

The best time to submit a soil sample

Article by Joseph Croze

soil samples in boxes along a bookshelf in the UConn Soil Nutrient Analysis Lab on the Depot Campus
Soil samples waiting for analysis at UConn. Photo: Joseph Croze

As most of you are probably already familiar with, the University of Connecticut is home to the UConn Soil Nutrient Analysis Laboratory. This lab is staffed by Dawn Pettinelli, the manager, and myself, the technician. We also have a few part time and student employees throughout the year that help with the receiving, spreading, and sieving of soil samples; among other things. We offer an array of tests designed to help homeowners, community gardeners, farmers, etc… maximize the efficiency of their soil to produce the greatest yields in whatever plant or crop they are growing, from silage corn to turf. We can test for soil organic matter content, textural fractionation, soluble salts, Nitrogen, and Carbon. We also provide tests for plant tissues and corn stalks. However, our most vital and popular test is the Standard Nutrient Analysis. This is a relatively comprehensive test that allows us to make limestone and fertilizer recommendations. We check the pH, add a buffering agent and then retest the pH. From there we are able to determine the soils capacity to resist the change in pH, this allows us to make an accurate and precise limestone recommendation, in lbs/1000 square feet, or lbs/acre, depending on the desired crop production. The second part of the Standard Nutrient Analysis is the actual nutrient content. Soil samples are analyzed for micro and macro nutrients; Potassium, Calcium, Phosphorus, Magnesium, Aluminum, Boron, Copper, Iron, Manganese, Zinc, and Sulfur. Samples are also screened for Lead. Using the nutrient results, we are able to make fertilizer recommendations based on what is being grown. We give results in N-P-K format, and also provide organic alternatives.

We get calls year round from customers asking if they can submit a soil sample, and the answer is always yes! You can submit a soil sample any time of the year, we receive soils from throughout the country (although we have to be careful of areas under certain quarantines). Generally, it only takes around a week from when we receive a sample for us to send out the results. As you might imagine, Spring is an extreme exception. We are so busy and backed up with thousands of soil samples right now, we are expecting a 3 week turn-around time. We understand that everyone is eager to get their hands dirty and work on their lawns and gardens, but waiting until Spring to submit soil samples isn’t the best idea.

Continue reading….

Soil Test Prices Have Increased

soil on shovelStarting July 1, 2016, the UConn Soil Nutrient Analysis Lab increased some of our fees as well as our offerings. The price of the standard nutrient analysis increased from $8 to $12. This is the test that is performed when a sample is submitted using those pre-paid soil test collection kits sold by some county offices. The standard nutrient analysis will now include sulfur, an estimated cation exchange capacity measurement and percent base saturation. A new interpretation sheet will be posted on our website. We are also increasing the costs of pH only and soluble salts tests from $3 to $4. The pH test is included in our standard nutrient analysis but sometimes a client just wants pH and not nutrients.


10 Tips for the March Gardener

  1. Make plans to attend the UConn Garden Conference on March 18, 2016.
  1. Carefully remove winter mulches and leftover debris from planting beds to reduce the presence of overwintering diseases and pests.
  1. Get your soil tested through the UConn Soil Nutrient Analysis Laboratory before any major planting or fertilizing venture. Soils sent in before April 1 will avoid the spring rush.
  1. Add limestone as recommended and, if possible, incorporate into planting beds but don’t fertilize yet. Wait until mid-April.
  1. As ground becomes workable, de-thatch the lawn if you find an inch or more of thatch; seed any bare spots. Get the lawn mower serviced, have the blades sharpened.
  1. Seeds of annual flowers and vegetables that require 10-12 weeks of growth before transplanting can be sown indoors now.
  1. Plant seeds of cold weather vegetables like spinach, peas, lettuce and broccoli as soon as soil is workable.
  1. Before new shoots emerge, cut back last year’s stalks on perennials and grasses.
  1. Horticultural oil treatments for maple bladder gall mite, spider mites on evergreens and scale on shrubs and trees can be applied; check labels for specifics on appropriate weather conditions.
  1. Eliminate any hard to mow areas such as acute angles in beds and borders. Combine single trees or shrubs into a large planting connected with ground cover. Put the birdbath in a flowerbed or surround it with ground cover.

For more information visit the UConn Home and Garden Education Center or call 866-486-6271.

Keep Phosphorus Out of Our Waters

By Dawn Pettinelli – Extension Instructor Plant Science & Landscape Architecture

phosphorusPhosphorus is an essential element for plant growth and as such is a component of many fertilizers. Many may not be aware that phosphorus pollution is the number one cause of declining water quality in fresh water lakes and ponds in Connecticut and other states. Phosphorus gets into the water from several different sources including failing septic systems, fertilizer applications, erosion of phosphorus-containing soil particles, and dissolved phosphorus from plant residues.

Phosphorus…Too Much Of A Good Thing

High levels of phosphorus in soil will not harm plants in your yard but it can adversely affect aquatic systems. Phosphorus stimulates the growth of algae and other aquatic plants leading to eutrophication, or lack of oxygen, in the water. Eutrophication occurs as the algae naturally die and decompose, lowering the oxygen level in the water causing fish and shellfish to die. As a result, water quality is diminished and the use of fresh waters is often restricted for drinking, recreation, fishing and other aquatic industries. In some states, 80 percent of water bodies are so affected that they are unfit for human recreation.

Eutrophication may cause serious health risks to both humans and livestock. Algal blooms of cyanobacteria can produce cyanotoxins which are poisonous and sometimes fatal to both man and animals if shellfish contaminated with the cyanotoxin are consumed.

A soil test before you go shopping can save you money; you may not even need phosphorus, or another of other commercial soil ammendments available.


10 Tips for the September Gardener

leaves-Deleware1.      Get a jump on next year’s lawn and gardens by having a soil test done through the UConn Soil Nutrient Analysis Laboratory.


2.      If the pH of garden and flower beds needs to raised, wood ashes may be used. Wood ashes have a pH of 11.0 and also contain phosphorous, potassium, and calcium. Use at 1 ½ times the suggested rate of limestone. (So if 5 lbs of limestone are called for, use 7.5 lbs of wood ash).


3.      Apply fall fertilizer to lawns between Sept. 15th and Oct. 15th.


4.      Watch for frost warnings and cover tender plants to extend the season.


5.      Rake up leaves, twigs, and fruit from crabapple trees to control apple scab disease. Do not compost.


6.      Remove the pesky seedlings of woody ornamentals such as maple or elm so that they don’t take over gardens and other landscape plantings.


7.      Continue to water any new shrub or tree plantings until the first hard frost.


8.      Plant asters and chrysanthemums for fall color in the landscape.


9.      Plant/transplant peonies now. Plant the crowns to a depth of one and a half to two inches below ground level.


10.  Stop by theCornucopia Festat the UConn Storrs campus on Sunday, September 21st, from 11:00 a.m. until 4:00 p.m. to get answers to your gardening questions. Bring a half-cup of soil for a free pH test.


For more information, please visit the UConn Home and Garden Education Center, or call 877-486-6271.


Photo: Delaware Extension

Fall Soil Testing

soilFall is the best time of year for testing your garden or lawn soil. Limestone and organic amendments can be mixed into the soil now, as they need time to breakdown and be incorporated into the soil. Come spring, only a planting fertilizer will be needed and you will have the recommendations in hand. Plus, the lab is not at busy in the fall as in the springtime so your results will be sent to you quicker. Interested? To find out more, go to

Liming Soils

by Dawn Pettinelli, UConn Home & Garden Education Center

Grd limestoneAn incredible number of chemical, biochemical and biological reactions occur in our soils. Through these reactions, nutrients, whether already present in the soil or added by fertilizers, are changed into forms that can be taken up by plant roots. The pH of the soil affects all these reactions thereby determining the availability of nutrients essential for plant growth.

Soil pH is a measure of the acidity of the soil. A pH of 7.0 is neutral with measurements below this number reflecting acidity and those above indicating alkalinity. Many native soils have a pH in the range of 4.5 to 5.5 while most of our vegetables, flowers and turf grasses prefer it to be between 6.0 and 6.8. Some notable exceptions are blueberries and broad-leaved evergreens, like rhododendrons, which require acid soils.

When the soil pH falls below 6.0, nutrients like phosphorus, nitrogen and potassium become less available to plants. Acid soils are also typically deficient in magnesium and calcium, two important plant nutrients. Another problem with acid soils is that elements like aluminum are much more soluble and may be taken up in quantities that can harm plants. On the other hand, a pH that is greater than 7.5 can also render nutrients unavailable.

Limestone is the material of choice to raise a soil’s pH. It neutralizes soil acidity while also adding necessary calcium and magnesium. Dolomitic limestone, which contains both of these elements, is most widely available and usually recommended. If the magnesium level of your soil is above optimum, a calcitic limestone which is composed mostly of calcium compounds is called for.

Limestone can be purchased in several forms with ground, pelletized and hydrated being the most common. Economically, ground limestone is your best buy but some do not like the dusty mess encountered when applying. Pelletized limestone consists of pulverized limestone that is formed into little pellets. Both take about the same amount of time to react in the soil, anywhere from 3 to 9 months depending on conditions. Hydrated lime is fast-acting but quite caustic and only warranted under specialized circumstances. Its effects on pH, however, are short-lived. Wood ashes can also be used as a liming agent at one and a half times the rate of the recommended limestone application.

How much limestone to add depends on your soil’s present pH, the desired pH, as well as the amounts of clay and organic matter in your soil. A soil test can best determine recommended amounts. Very acidic soils may require several applications to bring the pH up to a suitable level. As a guideline, for every 100 square feet apply no more than 5 to 7 pounds of limestone to the surface or 10 pounds tilled to a depth of 6 inches at one time.  Once you’ve attained a desired pH, 5 pounds of limestone per 100 square feet every other year usually will maintain that level.

For those that don’t want to guess how much limestone to apply, consider a soil test. Fall is the perfect time to test because any limestone recommended and applied will have time to start affecting the soil pH before spring planting season and, you’ll be avoiding the spring rush!  For information on soil testing, liming soils or any other home and garden question, feel free to call the UConn Home and Garden Education Center, toll-free, at 877.486.6271, visit us on the web at or contact your local UConn Extension Office.