Learn / Ask The Landscape Professional
To save money, my husband is thinking about buying mason's lime at the home improvement store to use on our lawn. Is that OK?
Answer
Oh No!
You should never use mason's lime on your lawn. Mason's lime is calcium oxide
which is highly caustic and can burn your lawn.
There are two types of lime that can be used on your lawn: "Calcitic lime" and "Dolomitic lime".
Although both are generally available at garden centers, they are very different products and
you need to know which one you need and how much to apply. Do not just buy any "Lime".
Over-enthusiastic liming with too much lime of the wrong type can be more damaging than
doing nothing. Many times, no lime is needed at all.
Turf grass grows best with a pH of 6.0 – 6.8. The function of lime is to raise the pH of acidic
soil so grass wants to grow. Below and above this range fewer macro and micro nutrients are
available. Both microbial and earthworm activity is affected by pH. Soils that are acidic tend
to be fungal dominant while soils that are between 6.0 – 6.8 are more balanced between fungi
and bacteria (which is what you want). Balanced microbial activity contributes to the availability
of nitrogen, sulfur and phosphorous in the soil. Earthworms, natural aerators of the soil,
also like a pH near neutral so their sticky coating does not dry out.
It is absolutely critical to soil test for pH, Calcium and Magnesium and other things to determine
how much and what kind of lime to use. The decision on which lime to use; calcitic or
dolomitic, is determined by the Calcium to Magnesium ratio. Both calcitic lime and dolomitic
lime contain calcium carbonate and magnesium carbonate, but the amount of each is different.
Calcitic lime has less than 5% of magnesium carbonate, whereas dolomitic lime has up
to 50% magnesium carbonate. If your soil is low in both magnesium and calcium you need
to use dolomitic lime, otherwise without realizing it, you may be raising the pH of your soil
while creating an imbalance in the calcium to magnesium ratio which creates other problems
(i.e., compaction and more weeds).
There is still plenty of time to soil test and if lime is needed it can be applied until the ground
freezes. Sprigs & Twigs can perform your soil testing and analysis and determine what and how
much of the correct type of lime is needed, if any. We will also advise you if any other corrections
should be made.We would be happy to apply the treatment or you can do it yourself.
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About Linda Lillie
Linda K. Lillie is the President of Sprigs & Twigs, Inc, the premier
landscape design and maintenance, tree care, lawn care, stonework, and carpentry
service provider in southeastern Connecticut since 1997. She is a graduate of
Connecticut College in Botany, a Connecticut Master Gardener and a national
award winning landscape designer for her landscape design and landscape installation work.
