Can I Use Hydrated Lime to Raise the pH of Soil?

About Hydrated Lime

• Hydrated lime can be found in most home and garden centers. Its chemical name is calcium hydroxide. Hydrated lime is produced by combining calcium oxide and water, which creates a chemical reaction and produces a fine white powder. Hydrated lime is also used to stabilize concrete and mortar and can be used to dry out manure piles and reduce insect and odor problems in animal carcasses. It has a high potency and acts much more quickly than other forms of lime.

Benefits

• Hydrated lime is a fast-acting soil amendment. It is much more reactive than ground limestone, which makes it a much faster neutralizing agent. It is also more potent than other forms of lime, which means that you will need much less. According to Michigan State University Extension, hydrated lime only needs to applied at a rate of 20 lbs. per 1,000 square feet. Ground limestone, on the other hand, needs to be applied at a rate of 50 lbs. per 1,000 square feet.

Warning

• Hydrated lime's potency and quick action can also be detrimental when it is misapplied. Some experts recommend avoiding hydrated lime for lawn use, as it can burn grass easily when used in excess. Although it is a bit less hazardous than oxide lime, also known as burnt lime, it is more difficult to apply than ground limestone and other forms of lime. As with any liming product, you should only apply hydrated lime after your soil has been analyzed, and always follow manufacturer's instructions carefully.

Alternatives

• Burnt lime and pelletized lime are two other types of quick-acting limestone. Burnt lime is also difficult to apply and can be hazardous when inhaled or touched. Pelletized lime is one of the more expensive forms of lime and requires more pounds per acre. The most common liming products are ground limestone and calcic limestone, which are the most readily available and cheapest forms. These forms are less caustic and dangerous than hydrated lime, although they are not as fast-acting.