Adding agricultural lime to the soil reduces its acidity, allowing nutrients to be taken up by the alkaline-loving plants growing in the soil.
However, there are many other uses for lime in the garden. Below you’ll learn about what lime does for the soil and how to use it in the garden.
Benefits of Garden Lime
Below are some advantages of adding lime to the soil.
1. Helps Improve Soil Activity
Generally speaking, plants are better able to absorb nutrients from the soil when there is activity going on there. Soil-forming factors that result from using garden lime include increased earthworm activities and a plethora of microorganisms working to improve the soil.
When the soil is acidic, these organisms cannot survive. As a result, this soil amendment makes the soil less acidic, creating a comfortable environment for beneficial organisms.
2. Adds Calcium to Soil
The primary active component in Agricultural lime is calcium carbonate. Therefore, you can use it to add calcium to soil with a low pH level.
Ag lime also contains a little magnesium, another nutrient that is essential for crop production.
3. Improves Soil Texture
Agricultural lime can help improve soil texture by allowing water to seep into the soil rather than puddling on top of it, thus also bringing water to the roots of the plants.
This will also help bind sandy soil and loosen clay soil, allowing it to drain more easily and better aeration.
4. Controls Garden Pests
Powdered lime is very dusty. As a result, certain insects are not able to breathe properly when it’s dusted on them.
It also makes it difficult for certain insects to crawl through it. However, you should exercise caution as ag lime might also affect beneficial insects.
Types of Lime for Soil
Homeowners and gardeners generally use two types of lime for lawns and gardens — dolomitic lime and calcitic limestone (agricultural lime). They come in either pelletized or powdered form, usually in bags.
Pelletized limestone, also known as pelletized lime, is what you see people spreading on their lawn using a broadcast spreader. The pellets fall through the blades of grass and stay above the ground. They are then watered in (or you can apply it before a light rainfall).
You can sprinkle lime dust at the base of individual plants and lightly scratch it around the roots.
Aglime comes from ground limestone rock which naturally contains calcium carbonate and magnesium carbonate. Dolomite lime, on the other hand, is similar to agricultural limestone but slower acting.
Both contain magnesium carbonate and calcium carbonate (which is what makes the soil alkaline). However, dolomite contains more magnesium.
Garden Plants That Need Lime
Plants that benefit from ag lime include parsnips, tomatoes, squash (winter and summer), legumes, asparagus, and lettuce. However, tomatoes especially need a soil pH near 5 or 6 (moderately acidic), so they’ll benefit from less lime than other vegetables.
Other lime-loving plants include onions, lavender, spinach, garlic, and cantaloupes.
Plants That Don’t Need Lime
Garden lime is not good for all plants. Plants that grow well in acidic soil, such as blueberries, strawberries, and grapes, would do better without lime application.
Additionally, for flowers and shrubbery, avoid using it on azaleas, daphne, rhododendron, and magnolia.
When to Apply
Agri lime needs time to work in the soil, up to a few months, depending on the weather conditions. It takes time to become active in the soil. As a result, some gardeners use it in the fall so it can dissolve before spring.
If you’ve recently moved to an area and aren’t sure about the soil pH levels, it’s a good idea to get a soil test done. Even if you’ve had the same garden and lawn for years, a lack of good crop rotation practices may have depleted your soil nutrients and changed the pH in some areas of your garden.
Most plants thrive well in soil with a pH between 6 and 7. However, plants cannot absorb soil nutrients if the pH is too acidic or too alkaline (too low or too high). As a result, testing is vital before applying lime.
The neutral pH level is 7.0. Anything below leans towards acidic soil, while pH greater indicates alkaline soil.
There are home soil testing kits you can get online and do it yourself, or have someone come over and do the testing for you. Moreover, the tests are not that expensive. They will also give you a good baseline knowledge about the kind of soil you have.
How to Apply Agricultural Lime
As noted earlier, the method of application will depend on which kind of lime you’re using and where you’re using it. Over a large area, such as a lawn, the push broadcast spreader would be the best method for applying the pellet form.
For a smaller lawn, there are handheld spreaders with a hand crank that sprays the pellets a few feet in front of you.
In the vegetable garden, you’ll want to treat individual plants by sprinkling garden lime powder around the base. For open plots, sprinkle it over dry soil and rake it in evenly.
How Often to Apply
The general time span for application to your vegetable garden is every two to three years. However, depending on your soil test results, you may need to apply lime annually or bi-annually if your soil is highly acidic.
Be aware of what type of lime you’re using for your fields. Also, follow the directions on the package for the correct application and the general safety precautions.
Quicklime (calcium oxide) and hydrated lime (calcium hydroxide) are caustic and are therefore not suitable for home gardens. Even with regular garden lime (aglime), which contains calcium carbonate, you should be careful when using it, as too much can be a bad thing.
Applied excessively, lime can burn plants, especially if the plant is already weak. Also, drought or frost can damage a plant, and the incorrect (generally, excessive) use of lime could damage it to the point of losing the plant altogether.
High alkalinity can also lead to Chlorosis, which is a yellowing of leaves as a result of the lack of chlorophyll. Additionally, it’s best to avoid fertilizing and liming at the same time as lime can neutralize fertilizers.
Where to Buy?
You can buy garden lime at most gardening centers or online from reputable organic gardening suppliers such as DoMyOwn.
Traditionally used in agriculture to alter the soil’s pH, lime helps plants absorb minerals and nutrients from the soil. However, exercise caution when using, as too much can result in very high alkalinity, which can lead to nutrient deficiencies in plants.