Dolomite lime is a natural soil amendment used by many gardeners and farmers to enhance soil quality and plant growth. This powdery limestone product contains high levels of magnesium and calcium carbonate which can balance pH levels, provide essential nutrients, and improve the physical structure of soil when applied properly.
What is Dolomite Lime?
Dolomite limestone contains large amounts of magnesium and calcium carbonate. It has an alkaline pH which can help neutralize acidic soils.
When added to soil, dolomite lime dissolves slowly over time to release essential minerals. Plants can absorb these nutrients more readily, leading to faster growth and more vibrant flowers and vegetables.
The fine texture of dolomite also enhances drainage and aeration as it loosens tightly packed soil.
Composition and Properties
Dolomite lime contains calcium carbonate (CaCO3) and magnesium carbonate (MgCO3) in roughly equal proportions. The presence of magnesium makes dolomite lime different from other liming materials like calcitic lime or pulverized limestone, primarily composed of calcium carbonate.
Dolomite limestone typically has a white, tan, pink, grey, or yellow color. Minerals in dolomite lime break down slowly over months after being incorporated into soil. This is due to the low solubility of the key minerals, especially magnesium carbonate.
Other important properties of dolomite lime include:
- Powdery texture, with most particles finer than an 80 mesh sieve
- pH in range of 7 to 8, making it alkaline
- High purity in chemical formula
- Origins from ancient marine deposits and coral reefs, now mined
The mineral composition and physical traits make dolomite lime conducive for use in agriculture and gardening as an effective soil amendment.
Benefits and Uses
Dolomite lime provides a wide array of benefits as a soil treatment due to its high pH and rich presence of essential minerals. Key advantages include:
Balancing acidity – It counteracts acidic soil conditions to create a neutral pH range ideal for plant growth and nutrient availability.
Adjusting soil pH – It gradually corrects overly acidic soils and slowly raises pH levels into the optimal zone over a period of months.
Supplying calcium & magnesium – These minerals are vital for plant growth and challengeing to obtain in very acidic soils. Dolomite provides a slow-release source.
Improving soil structure – It enables better water penetration, drainage, root development and oxygen circulation to benefit plant roots and microorganisms.
Releasing other nutrients – By balancing soil pH and providing key minerals like calcium and magnesium, dolomite allows better availability of immobile soil nutrients.
Facilitating fertilizer uptake – More effective utilization of applied fertilizers is enabled by proper pH levels and improved soil structure.
Enhancing plant resilience – Healthier growth enabled by dolomite lime improves plants’ ability to withstand diseases, pests and drought conditions.
How Does Dolomite Lime Work?
Dolomite lime improves soil in several ways to create better conditions for plant growth and crop yields. The key mechanisms it utilizes are:
Improving Soil pH
By raising pH levels, dolomite counters the high acidity that prevents plants from accessing nutrients in the soil. It also reduces toxic elements like aluminum and manganese to levels that plants can tolerate.
Most plants grow best within a pH range of 6 to 7. However, certain soils have acidic conditions below pH 6 due to rainfall, fertilizer use, and mining of nutrients by crops over time. The acidic environment causes nutrient imbalances and allows toxins like aluminum to rise to excessive levels.
Dolomite lime contains alkaline minerals like calcium and magnesium which can neutralize acidity. As it dissolves over time, these minerals combine with hydrogen ions in the soil, reducing acidity levels. This raises soil pH incrementally over a period of months into the optimal zone.
Providing Nutrients
The calcium and magnesium in dolomite lime are essential minerals that benefit plants in many ways. Calcium strengthens cell walls and improves the uptake of other nutrients. Magnesium is a key component of chlorophyll for photosynthesis. Dolomite releases these slowly over time.
Calcium plays crucial roles in plant growth, including:
- Development of cell walls and membranes
- Regulation of nutrient uptake
- Supporting enzyme activation
- Facilitating plant resilience and disease resistance
Magnesium aids plants through:
- Forming chlorophyll molecules for photosynthesis
- Assisting metabolism of carbohydrates and nutrients
- Enabling efficient water and nutrient transport
- Helping with the creation of vitamins, enzymes and sugars
By releasing a steady supply of these nutrients from its mineral content, dolomite lime provides calcium and magnesium over an extended period without the need for immediate plant availability unlike synthetic fertilizers.
Enhancing Soil Structure
The calcium in dolomite lime helps soil particles bind together to form stable clumps with space for water drainage and air circulation. This creates a better habitat for plant roots and beneficial microbes.
Dolomite lime can improve the structure of clay soils, sandy soils and compacted soil through:
Improving clay soil structure – Calcium enables separate soil aggregates to form, improving drainage and aeration. Magnesium replaces sodium attached to soil particles, allowing better aggregation.
Increasing sand soil moisture retention – Minor cation exchange properties enhance microscopic moisture retention for improved growth.
Loosening tightly compacted soils – Slow dissolving lime crystals physically displace particles that restrict water and air movement needed for plants and microorganisms.
The long term enhancement of soil structure promotes healthier root systems, increased biological activity, better drainage and water retention capabilities. This leads to stronger plants.
When and How to Apply Dolomite Lime
Getting the most out of dolomite lime requires proper timing, dosage and application to garden beds or agricultural fields. Key steps include:
Testing Soil pH
The first step is to test your soil pH and determine how much it needs to be adjusted. Acidic soils with a pH below 6 may need dolomite applications to reach an optimal range between 6 and 7.
Use a soil pH testing kit on several representative soil samples taken across areas planned for planting. If adding lime for the first time, test soil to full depth of plant roots – up to 6 to 18 inches below surface.
Adjust dolomite lime dosage based on test results and product instructions. Severely acidic soils may need very high initial applications up to 100 lbs per 100 sq ft for lawns or 50 lbs per cubic yard for gardens.
Determining Application Rate
Follow package instructions based on your soil test results, or consult your local agricultural extension office for advice on adjusting application rates.
General dolomite lime application guidelines per 100 sq ft of area are:
- Lightly acidic soil – 5 to 10 lbs
- Moderately acidic soil – 20 to 40 lbs
- Very strongly acidic soil – Max 100 lbs
Application rates may be lowered after initial correction by testing soil pH every 2-3 years and making minor pH adjustments as needed through smaller doses.
Spreading Evenly
Use a spreader for even coverage across all planting beds and gardens that need pH adjustment. Dolomite lime should be incorporated into the top 2 to 6 inches of soil through rototilling or raking.
When spreading, make sure to overlap passes and use a consistent walking pace for optimum coverage. Break up any clumps larger than 1 inch before incorporation. Blend thoroughly into the top layers of soil so dolomite can dissolve effectively.
Timing of Application
It’s best to apply dolomite lime 2-4 weeks before planting so nutrients will be available for crops. This gives moisture and root growth cycles time to dissolve some minerals. Fall applications for summer crops also work well as plants go dormant.
Avoid applying dolomite lime shortly before seeding sensitive crops or during freezing weather when soil improvement reactions cannot take place. Adjust timing appropriately for your climate and growing seasons.
The Impact of Using Dolomite Lime
Applying dolomite lime at the right dosage and schedule can lead to noticeably healthier plants, improved resistance to pests and diseases, and higher yields.
Healthier Plants
Balanced pH and increased nutrient intake leads to faster growth, more flowers and fruit, and better resilience against diseases. Unique minerals in dolomite also boost plant metabolism and photosynthesis.
With essential nutrients readily available, plants will display optimal growth patterns, more vigorous shoots and greener foliage. Flowers and vegetables will mature faster with higher quality.
Correcting overly acidic soil also increases beneficial microbiological activity around plant roots through bacteria and mycorrhizal fungi essential for nutrient cycling and uptake.
Increased Nutrient Availability
Calcium and magnesium in dolomite promote the release of other essential nutrients in the soil so plant roots can access them more easily. Toxic levels of aluminum and manganese are also reduced.
By balancing soil pH near neutral levels, dolomite lime enables healthy solubility and mobility for critical secondary nutrients like sulfur, iron and boron needed in lower levels.
As plants grow bigger and stronger with minerals provided by dolomite lime, their roots will spread wider and deeper to utilize more nutrients naturally present in soil that were previously locked up under acidic conditions. This abundant nutrient access fuels plant development.
Balanced Soil pH
Bringing pH into the optimal range through dolomite lime allows plants to thrive. It also creates the ideal environment for beneficial microorganisms like bacteria and fungi to colonize plant roots.
The improved biological activity accelerates natural soil processes like decomposition of organic matter, nitrogen fixation, and chelation cycles that make nutrients bioavailable to plant roots. Healthy microbial populations digest minerals and convert them into plant-usable forms.
These advantageous soil conditions propagate across future seasons after initial pH correction and faithful dolomite lime application schedules are maintained. This maximizes the long term benefits.
Choosing the Right Dolomite Lime Product
When purchasing dolomite lime, gardeners and farmers should evaluate purity levels, mineral content, texture, and potential lead contamination based on product origin.
Purity & Mineral Content
Choose a high purity dolomite lime containing at least 90% calcium magnesium carbonate by volume to avoid fillers that will not effectively raise soil pH or supply essential minerals.
Magnesium level near 20% is ideal, as high calcium variations lose soil conditioning advantages. Secondary trace nutrients suitable for plants may also be present.
Texture
Powder or fine pulverized dolomite lime has faster reaction time and dissolution rate after soil incorporation compared to granular pellets. But pelletized lime offers easier and more uniform spreading.
Consider how well your equipment can apply each texture. Powders may stick inside spreaders or blow away easily during windy conditions.
Lead Contamination
Some dolomite lime contains concerning lead levels from surrounding ore deposits present at mining sites. The EPA limit is 400ppm lead.
When possible, use dolomite lime quarried far away from metal mines or lead smelting sites which can cause contamination. Always request lead safety lab certificates from the lime producer before purchase.
Following these parameters when selecting which dolomite lime product to purchase will lead to ideal soil improvement outcomes. By properly amending soil pH, supplying essential plant nutrients, enhancing drainage and moisture retention, dolomite lime allows farmers and gardeners to increase yields and grow healthy, thriving crops and vegetation.
Overcome Acidic Struggles With Dolomite Lime
Dolomite lime is a valuable soil amendment for gardeners and farmers seeking to strike the right balance of nutrients and minerals that plants need to overcome acidity, structural issues, diseases and nutrient deficiencies. Introducing this alkaline liming material safely, after careful soil testing and selection of high purity dolomite lime, can lead to visible improvements in plant vigor within a single growing season. The lasting corrections in soil pH and gradual nutrient additions from ongoing applications set the stage for thriving, healthy and productive gardens and farms.
Frequently Asked Questions
What’s the difference between dolomite lime and calcitic lime?
Dolomitic lime contains equal proportions of calcium and magnesium, while calcitic lime is almost pure calcium carbonate without an abundance of magnesium. Dolomitic lime adds crucial magnesium lacking in most acidic soils.
When is the ideal time to apply dolomite lime?
It’s best to apply 2-4 weeks before planting crops so the minerals can start to interact with soil. Early spring or fall are great times as the lime can break down over winter. Avoid winter applications in freezing climates.
How long does dolomite lime take to raise pH in soil?
Soil pH increase happens slowly over months as soil cycles and moisture dissolve the minerals. The full neutralizing effect occurs over 1 to 2 years. Re-test soil pH again after 6 months to check results.
What’s the maximum amount that should be used?
Initially up to 100 lbs per 100 sq ft can be used to correct very acidic soils with pH below 5.5. This level should be worked into the top several inches of soil. After that avoid exceeding 20 lbs per season.
Does dolomite lime get rid of moles or voles?
There is no scientifically proven effect of dolomite lime on controlling burrowing pests like moles. However, improving soil health can help reduce food supply insects like grubs that these mammals eat.
Can too much dolomitic lime harm plants?
Excess applications over extended periods can push soil pH too high above 7.5, limiting nutrient availability. Use less if soil becomes very alkaline. Signs like yellowing leaves indicate excess alkalinity.
How does dolomite compare to wood ash to raise pH?
Wood ash and dolomite lime both counter acidity effectively. Dolomite is preferred as it delivers more steady nutrient additions and won’t shift soil pH as radically as wood ash if over-applied.
Is there lead in dolomite limestone?
Some dolomite contains higher lead content from surrounding mineral deposits where it formed. Always review safety certifications from the quarry source before purchase. Dolomite from cleaner sites offers negligible lead risks.
Can pelletized lime dissolve and alter pH as well as powder?
Pelletized lime works effectively to change soil acidity though more slowly than a Pulverized powder that has greater particle surface area exposure to soil. Either format provides lasting pH adjustment.
How does dolomite lime compare to crushed oyster shells?
Both contain abundant calcium carbonate to effectively neutralize soil acidity. Oyster shells offer a renewable, sustainable waste material source but provide less magnesium. Dolomite lime is mined.
