How to Adjust Soil pH for Vegetable Gardens

Updated on March 7, 2018
Jeanne Grunert profile image

Jeanne Grunert is a Virginia Master Gardener, gardening magazine columnist, and book author. She is a full-time freelance writer.

Vegetables benefit from the right soil pH.
Vegetables benefit from the right soil pH. | Source

Soil pH for Vegetables

If you slept through high school chemistry class, never fear. You can still learn the basics of soil pH for vegetables to ensure a great garden this year. pH refers to the scale of acid to alkaline, a scale developed in the early 20th century by chemists trying to describe the range of pure acid (0) to pure alkaline (14) of chemistry in the world. The pH scale runs from 0 to 14, with 7 being at the very center. Most vegetables thrive in a slightly acidic environment, and, indeed, most plants need a soil pH of 5.5 to around 7.0. That range is variable and flexible, however, and depends greatly on the type of vegetables you're trying to grow in the backyard garden or, in the case of blueberries, fruit. Some plants, such as the aforementioned blueberry, need a highly acidic soil. Few need a deeply alkaline soil.

So given that you just want to grow a few tomatoes or some lettuce, what do you really need to know about the acid and alkaline base? What do you need to know about soil pH for vegetables? I'll give you the basics of soil PH, pH testing for soil, and other ways to analyze your soil below, along with some simple ways of adjusting the soil pH if you have to do so.

Note that I say "if you have to do so." You shouldn't try to drastically change your soil pH without first consulting someone from your local County Cooperative Extension Office or another expert. Once you drastically alter your soil pH, it can be difficult to get change it back. It can get costly and time consuming. Be certain of your soil pH before adding anything to change it, and have your soil tested and analyzed by a professional laboratory before adding vast quantities of additives. Most of the time, you can and should adjust soil pH gradually and slowly using natural additives such as compost and peat moss. You really can't go wrong adding compost to the soil.

How to Test Soil pH

You can have your soil analyzed professionally at a laboratory, take a sample to a garden center or another location that tests soil, or purchase a test kit and test it at home. All three methods have pros and cons, and all three will yield a basic soil pH reading that will help you understand your soil's chemistry and potential additives it needs. If you have your soil professionally tested through an independent laboratory or a garden center, they should be able to analyze other aspects of soil compositions such as particle size and organic material. These three points of information - pH, particle size (which tells you your soil type) and organic matter - can help you better understand what your vegetable garden needs in order to grow more abundant, tastier vegetables.

How to Test Soil pH: Soil Collection Basics

No matter which route you pursue, the basics of collecting soil are the same.

  • Use a plastic bag or a plastic or glass container to transport soil samples. Don't use a metal container, as metal has the potential to contaminate the readings.
  • Scoop approximately 1/2 cup of soil from several locations around the potential garden area into each soil container. Keep them separate from one another, and mark or label the container with the location and date of sample collection. Dig down a few inches but not too far for the samples. Don't take it right off the top.

Taking several samples yields a more accurate test result than a single sample. For example, my garden on Long Island had odd stripes of clay alternating with sand. If I had just taken a soil sample to the lab from the clay area, the result would be different than if I had taken a sample from the sandy area.

If you're taking soil samples at home, follow the pH test kit instructions to test your soil. Once you know the results, write it down in your garden journal or somewhere you can keep track of it.

Those taking soil samples at home may also want to consider conducting an at-home test to determine how much organic material is in the soil. You want plenty of organic material in the soil; it feeds the soil colonies of bacteria, microbes, worms and insects that make for happy plants. Here's how to determine the type of soil you have (clay, loam, sand) and how much organic material is in the soil.

What’s My Type? Do-It-Yourself Soil Test

You’ll need…

  • Clean glass jar, such as a clean and dry mayonnaise or pickle jar
  • Soil from your yard
  • Water
  • Marker

Fill the jar about 2/3 full with water. Now fill the jar with soil, leaving about 1” from the top free of water and soil. Put the lid of the jar on very tightly. Shake the jar back and forth vigorously for about a minute. Now put the jar down on the countertop. Let the soil settle. After a minute, put a mark on the jar next to the first layer that settles out. This tells you about how much sand you have in your soil sample. Allow the jar to sit for an hour, and place another mark on the next layer. That’s your silt later, and shows you how much silt is in your soil. Allow the jar to sit for a full 24 hours, and place your last mark on the top layer. That’s the amount of clay in your soil.

Depending on the amount of each element – clay, silt or sand – you’ll know what you are dealing with. No matter what type of soil you have, adding organic material can improve it.


Adjusting Soil pH

Soils generally fall into the acidic range or the alkaline range. Most garden vegetables thrive with a soil pH of around 6.5 or so, but know your veggies - check on individual vegetables if you're not sure what each one needs.

Acidic Soils

Acidic soils have a pH around 5.0 to 6.0. Garden lime adjusts the soil pH gently for acidic soils. Follow the package directions and add lime according to the amounts per square foot as indicated on the package. Acidic soils are actually fairly common in the United States.

Alkaline Soils

Alkaline soils soil types generally register a pH of 7.0 to 8.0. Powdered sulfur is used to lower soil pH in alkaline soils. As with adding lime, read and follow the package directions for the amount of sulfur to add and frequency of application.

All Soils Benefit from Compost

It doesn't matter what your soil pH reading is...all soils benefits from compost. Compost is nature's ultimate soil booster. You can compost banana peels, coffee grinds, eggshells, fruit and vegetable peels, leaves and grass clippings. You don't even need a fancy compost tumbler or bin. I've made compost bins from stacks of bricks and blocks, an old dresser drawer on the ground, and a garbage can with holes cut in the side for ventilation. The point of composting is to allow nature to break down the organic materials into the elements that feed the soil and in turn, feed your plants. A good well-rotted animal manure such as cow manure, horse manure or chicken manure also boosts soil fertility. Just don't compost meat, bones or similar items; they attract vermin.

Test Soil Frequently

After testing your soil, adding compost and planting a garden, it's a good idea to test soil annually or at least every two years. Soil pH can change over time. It's important to work slowly with soil, too, and never dump a lot of amendments on it at once. The only exception to that suggestion is compost. You really can't go wrong adding plenty of good old fashioned compost to the soil. Test your soil each spring before planting, add amendments as recommended, and record the results. Over time, your garden will reward you with abundance.

© 2011 Jeanne Grunert


    0 of 8192 characters used
    Post Comment

    • profile image


      6 years ago

      Never learned before this.

    • GmaGoldie profile image

      Kelly Kline Burnett 

      6 years ago from Madison, Wisconsin

      The ph level for the soil and for the water in the hot tub are confusing for me. I love gardening must become more atuned to this important element. The ph level is akin to my resting heart rate that I track on a regular basis and advise my fitness clients to do as well.

      I never learned before your article how often to test the ph level of the garden soil - 2 years is a great standard that I will follow.

      Excellent article! Thank you very mu

    • Donna Sundblad profile image

      Donna Sundblad 

      6 years ago from Georgia

      Very useful information! I've given you a vote up.

    • carol3san profile image

      Carolyn Sands 

      6 years ago from Hollywood Florida

      Great advice. I'd love to have a garden but cant because I live in a condo. But I have one at my mom's which I enjoy working in. So far we've only grown tomatoes and collard greens.

    • DonnaCosmato profile image

      Donna Cosmato 

      6 years ago from USA

      Awesome but simple advice! I'm sharing this with my fellow gardeners.

    • Kim M Gregory profile image

      Kim Morgan Gregory 

      6 years ago from The Coast of The South Carolina Lowcountry

      Great article.

    • homesteadpatch profile image


      6 years ago from Michigan

      Great information. Improving soil can seem like an uphill battle, especially in the beginning.

    • carcro profile image

      Paul Cronin 

      6 years ago from Winnipeg

      Really good Hub, I never new gardening could be so complicated, but then judging by my tomato crop this year I could have used this Hub sooner, lol. Thanks for sharing this...Voted Up and USeful!


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)