I'll probably apply some calcitic lime over one of the last snow falls in
early February, and rely upon the melting snow to carry the lime into the
soil. I read that lime is slow-working and it can take 3 to 5 months for
the soil and lawn to reap the lime's benefits.
The only problem is I've only seen dolomitic lime at the big box stores,
not calcitic lime which has a better ratio of calcium to magnesium (7:1)
than the dolomitic stuff. Tukey's book says too much magnesium in the
lime in relation to the calcium isn't ideal for your soil. You want
a 7:1 calcium to magnesium ratio in the lime, not 3:1 or anything else
for pampering your soil the best.
Would anyone know where I can get calcitic lime in the St. Louis area?
Worm's Way maybe? I'll give them a call.
I found this great, informative page about applying calcitic lime
and/or dolomitic lime to the lawn and garden. The page is from
Home Depot's web site, but I'm going to reproduce it here in case
Home Depot ever takes the page down. I want to be able to
review the info on this page each year when it's time for me to
To be fair to Home Depot, I'll provide a link to their web page:
From Home Depot:
Improve the soil in your lawn or garden using lime and gypsum
Although lime and gypsum are both used to improve the soil in your lawn
and garden, they serve very different purposes. Adding lime to soil
raises the pH so it becomes less acidic. This can help increase vegetable
production in the garden and enhance the appearance of your lawn. Gypsum
is often used as part of a strategy to correct compacted soil or soil
with large amounts of clay. It can also be used to counteract excessive
saline levels in soil and has the added benefit of not affecting the pH
of soil. Before you prep your soil with lime or gypsum, consider the
* Have you tested the pH level of your soil?
Should you apply lime and fertilizer at the same time?
* Is there clay or a hard layer of topsoil in your garden?
Do you live in an arid or maritime climate?
Lime, Gypsum and Application Tips
The best way to determine whether or not your soil needs liming is to
test its pH. Since the most fertile gardens and lawns are those with a
proper pH balance, having your soil tested every few years is highly
beneficial. The target pH level of turf grass, for example, is between
6.2 and 6.5, so if your soil has a lower pH it will likely benefit from
the addition of lime. Remember, though, too much lime can be as harmful
to your lawn as too little, so always test the soil and read the
instructions on the lime package before application. To determine if a
soil can benefit from gypsum, you can test saline amounts or simply
observe if you are working with soil that is heavy with clay or hard to
break up. Although it may be tempting to apply your lime, gypsum and
fertilizer at the same time, it's not a good idea to introduce too many
chemicals at once.
Lime: Lime is a compound made up of calcium or calcium and magnesium and
is used to reduce the damaging effects of acidic soil on lawns and
gardens. Lime also reduces the toxicity of elements in the soil, such as
aluminum, manganese and iron, which can adversely affect plant growth.
Lime also adds desirable nutrients, such as calcium and phosphorus. In
addition, lime increases bacterial activity, which helps improve soil
structure. The two most common types of lime used in gardening are
calcitic lime and dolomitic lime.
* Soil in the eastern U.S. often requires the addition of lime to
Calcitic lime is pure calcium carbonate and is the cheapest form of
* Dolomitic calcium contains calcium carbonate and equal parts of
Vegetables thrive best in a slightly acidic soil, with a pH between
5.8 and 6.3
* Adding too much lime to soil can damage it as much as having high
Gypsum: Gypsum is actually an element called calcium sulfate that is used
to loosen up stubborn, compacted or clay soils. Gypsum works by pulling
together clay particles in the soil to make bigger particles, creating
porous spaces for air, water and plant roots. For saline-infused soil,
gypsum removes sodium and replaces it with calcium. For all soil types,
gypsum adds calcium and sulphur, which are necessary elements for plant
growth. Gypsum also helps soil retain water and helps decrease soil
* Gypsum will not alter pH levels and is relatively inexpensive and
easy to use
Soil in the southeast U.S. often contains clay and may benefit from
* Arid and coastal regions that feature high soil salts can benefit
Gypsum prevents surface crust deposits on soil that adversely
affect seed emergence
* Gypsum can correct lawn damage from salt and other winter ice-
Application Tips: It is easy to apply lime and gypsum using a drop
spreader or broadcast spreader. Since lime is insoluble, it tends to stay
exactly where it is spread, so these devices ensure uniform coverage.
Gypsum is neutral and does not change the pH of your soil so you can use
it around acid-loving plants, such as rhododendrons and azaleas, to
provide extra calcium. As with all fertilizers, apply lime and gypsum as
directed on the label. Both substances are safe to use and are nontoxic
to humans and plants.
* Although best applied in the fall, lime can be applied at any time
For even coverage, apply half the lime in one direction and the
rest in a crisscross pattern
* Apply lime and fertilizer at least two weeks apart to avoid
Both lime and gypsum can be easily applied using lawn spreaders
* Lime can burn a lawn if misapplied, but gypsum will not
Consult the chart below to learn more about how to apply these useful
substances to your lawn and garden.
Calcitic Lime: Mined from natural limestone, calcitic lime is then
crushed up into finely ground powder granules. Pelletized lime is created
from finely ground lime plus a cementing agent that is added to form
pellets. Pellets are more expensive but easier to use and eliminate the
dust problem of granular lime. Pellets dissolve in water so it's
important to water thoroughly after application. Calcitic lime also
contains calcium, a necessary element to encourage healthy plant growth.
Calcitic lime is most often applied to lawns but may also benefit garden
plants, shrubs and flowers.
Dolomitic Lime: Dolomitic lime is mined in the same manner as calcitic
lime and is also crushed and sold in either finely ground powder form or
pellets. Dolomitic lime provides both calcium and magnesium. Dolomitic
lime is most often applied to lawns but may also benefit garden plants,
shrubs and flowers.
Granular Gypsum: Gypsum is ground up into a fine, white powder and sold
in the form of granular gypsum, which is applied using a lawn spreader.
Granular gypsum may be applied to turf grasses, garden plants, shrubs and
flowers. Finely ground formulas are rapidly available to plants and soils.