For an extended period of time, lime use for organic gardening has been a contentious substance.
Some people claim that it’s completely safe to use, while others advocate against its use.
In fact, the US government prevents commercial organic farmers from using lime.
Lime is an a purely natural (organic) fertilizer. A fertilizer which is added to the soil to change soil PH to lower soil acidity or lower it.
Lime, as a fertilizer, can promote better nutrient uptake and is probably the most cost-effective way to gain additions of calcium and magnesium.
Why Is Lime an Organic Fertilizer
As mentioned before, natural fertilizers are made of natural inputs without added chemicals.
Lime is produced from ground limestone rock, and naturally contains calcium carbonate and magnesium carbonate.
There are some other liming materials that are homemade; those materials include crushed eggshells or dried crushed oyster shells, made mostly from calcium carbonate.
The positive feature of lime is that it contains calcium and magnesium, which are plant nutrients for growth, but lime just can’t be a fertilizer.
To summarize: Lime is used for soil pH improvement or to lessen the acidity of soil to open the availability of nutrients to the plants, and the lime is only applied when plowing, or preparing the land.
Types of Lime
Agricultural Lime
Garden lime is also called agricultural lime.
It is made from chalk or pulverized limestone.
It improves pH and adds calcium for crops to trace nutrients.
You can use extra rock dust which can benefit the soil as well and adds nutrients to the soil.
Dolomite Lime
Dolomite lime resembles agricultural lime, although it has a greater percentage of magnesium.
This lime is suitable for use in organic gardening, however, the use of dolomitic lime should always be modulated by an understanding of soil pH and magnesium level.
Quick Lime and Slaked Lime
Quicklime is produced from burning limestone rock in kilns.
It’s very caustic and it is not recommended to use it directly into the soil.
Water is added to quicklime to create hydrated or slaked lime.
The lime is placed in the garden in the hips for the purpose to absorb water turning it into slaked lime.
Once this completed product has formed slaked lime, it can then be spread out onto the soil.
Important: It is not recommended to use quicklime as its efficacy as organic fertilizer is short-lived.
How Does Lime Benefit Your Soil?
Lime greatly improves soil quality by neutralizing the effects of acids that come from nitrogen fertilizers.
Acid soils are soils with a low pH, and lime will increase soils pH and make the soil moiré alkaline.
When the pH of the soil is below the low range, this will reduce the crop yields.
It’s important to understand that both crop species require a range of pH for crop to yield well.
An even soil pH helps good root development and improves soil structure.
Good root development helps the plant trace the essential elements, this can improve the crops yield.
This type of organic fertilizer enhances the major nutrients like nitrogen, phosphate, and potassium by:
- Enhanced nitrogen fixation in legumes and free-living bacteria.
- Increased release of phosphate, potassium, and nitrogen from the organic matter via higher microbial activity.
- Release of phosphate from iron and aluminum.
- Reduced leaching, which reduces the loss of potassium.
Lime increases the availability of sulfur, calcium, and magnesium by:
- Reduce leaching to minimize Norfolk depletion of magnesium and calcium
- Enhanced release of magnesium, calcium and sulphur from organic matter due to microbial activity
- Supplying magnesium and calcium
- Lime has the added benefit of a long term investment
- Lime helps crops and roots grow
- Builds and maintains soil structure
- Helps to slow down the movement of heavy metals
- Requires and builds Organic Matter
- Lime helps to reduce soil acidity
- Helps to increase the efficiency of fertilizers and agro chemicals
- Helps to release more reserves of nutrients in the soil
- Helps to slow down the activity of heavy metals
- Helps to reduce leaching loss of nutrients
How Much Lime Does Soil Need
The quantity of the fertilizer will be influenced by the pH of your soil and its consistency.
You will need to do a proper soil test because you cannot judge how much lime you will need to use in the field.
If you wish to apply lime, it is not advisable to use a home pH test kit, which is not a true measurement of the type of soil, but only a measurement of the acidity level.
If you want a true soil test to be performed, it should be performed by a laboratory.
A laboratory will also then recommend the appropriate application to meet the needs of your soil.
To determine pH of the soil, and if your pH of the 0- to 3-inch layer of soil is below 5.5, you will need to topdress your soil with 25 to 50 pounds (9-23 k) of ground limestone per 1000 square feet (93 m2).
Good to know: When establishing a new lawn you will be required to test the soil and then the recommended rate mixed into the soil. If your soil has too much acidity or too much clay you may need to apply as much as 100 pounds (46 k) per 1000 square feet.
How And When to Apply Lime
Once you have had the soil tested, you will be able to estimate the amount of lime you can utilize.
A certain section of your field may be more acidic than the rest, so it is wise to test the entire field.
Specifically, a plan for the lime application is developed to ensure you do not under apply or over apply lime over the entire field.
There are some crops that may vary on how much lime they should take; it is based on their needs.
As a rule, apply lime to acidic areas of your garden no later than six months before planting another crop.
Also, it may be applied before or after that, sort of however you will.
It is critical to apply the lime as deep into the soil as you possibly can. If the lime is applied too close to the surface, it may take longer to dissolve and may not be effective for the plant and the soil.
Of course; plants whose roots do not go deep into the soil and do the majority feeding sort of close to the surface may not be bothered by that.
But there you must consider tilling.
Here are seven signs you know that your garden requires lime.
That is when:
- The grass growing on the land becomes yellowish.
- There are many weeds on the land. Weeds prefer to grow in acidic soil.
- Fertilizers do work on your crops, but the profits may be small.
- Moss growing at the base of the trunks of your trees and climbing into the anchor positions of your land.
- Your land is sandy or clay, and they require lime applications periodically.
- Torrential and consecutive rainfall happens, and this will require you to incorporate lime as every drop of rainwater extracts calcium and magnesium from the land.
- The land is depleted in recovering from drought.
Plants That Mainly Benefit from Lime
When you’re developing a vegetable garden, plants that will be especially beneficial to lime include legumes such as broad beans and peas.
Other leafy vegetables that will benefit from lime include English spinach, celery, daffodils, lettuce, onion, garlic, parsnips, and asparagus.
Some plants don’t like to lime including:
- potatoes
- rhododendrons
- ericas
- blueberries
- camellias
- and azaleas
Final Thoughts
Lime is known as an organic fertilizer; however, you should not use it as a fertilizer.
Lime is mostly used to modify soil pH and neutralize excess soil acidity. Lime is also fairly necessary in your garden because it represents a source of nutrients, such as calcium and magnesium.
Lime is spread before planting and not on planting seedlings or established seedbeds.