Facts of Lime

What is AgLime?

• It's common knowledge that agricultural lime is one of the key factors for getting soil structure in top growing condition, yet how and why it should be used is less clear
• AgLime is a completely natural product. It improves the quality of the soil structure by neutralising soil acid, and providing nutrients and trace elements
• By using AgLime to get the soil condition right from the outset, there are many benefits that follow. Because soil conditions are right, other fertiliser applications are much more effective. Good soil structure encourages grass and clover growth which improves feed quality and pasture palatability
• Unlike many fertilisers lime has no harmful effects on the environment as it is a natural product

Types of Agricultural Lime

• Real agricultural lime contains 85-100% Calcium Carbonate (CaCO₃). Agricultural lime that contains higher levels of the active ingredient (CaCO₃) is more pure, which means it is more efficient in improving soil conditions
• Graymont AgLime is Fertmark certified to contain a minimum of 90% CaCO₃ and we are one of New Zealand's leading agricultural suppliers

Why put on AgLime?

• Using lime gets the soil composition right; more worms, more nutrients available and more growth
• Lime has been referred to as 'the big purifier'. It raises or maintains the soil pH at the ideal level (pH 5.8 - 6.2), which stimulates the soil nutrient cycle. It encourages worm and bacterial activity which aerates the soil and improves drainage and it also enhances the decomposition of plant matter and dung
• There are already a lot of nutrients in the soil, yet many are not available to plants when the soil pH is at the wrong level (see Fig. 1). Once the soil is restored to the right pH level, these nutrients are more able to be taken up by plants
• AgLime enhances decomposition-the breakdown of dead plant matter and dung-all part of the biological cycle. If dung pats are not breaking down, leaves are not decomposing quickly, or grazing is considerably patchy, this is often a sign of low pH

What does AgLime do to the soil?

• It raises the pH level to provide the best conditions for growing pasture.
• AgLime improves soil quality by lifting the soil pH level. This encourages earthworm and microbe activity, which improves overall soil structure and root development, essential for vigorous, healthy pasture
• Getting the soil pH at the ideal level (between 5.8 - 6.2) has a great effect on nutrient availability...
• This balanced environment also ensures fertiliser applications are fully utilised, and because of this, on farm results have shown fertiliser application can be reduced by approximately 25-40%!

Using lime to lift the pH makes poisonous elements less available:

Aluminium

• If soil pH is below 5.5 the aluminium solubility locks up phosphate so it can be used effectively by the soil

Manganese

• More manganese is evident when soil has a low pH. This will make the pasture less palatable for the stock. Excessive manganese can also be poisonous to young stock

How often should you spread AgLime?

• It's best to cover the whole farm every year. This keeps it in top condition for applying fertiliser
• Results show that whole farm lime applications produce the most outstanding results, and don't actually cost a lot. With yearly liming, pastures regenerate better, are more able to withstand the demands of grazing rotations, and also reduces the effects of a drought
• AgLime provides a basis for all other fertiliser applications. By keeping soil in top condition, you will get much more out of the fertiliser you apply. When soil is in top condition, it makes much better use of existing nutrients. Results have shown fertiliser applications can be reduced cutting fertiliser costs significantly, which means more profit per hectare
• The best time to apply AgLime is in early summer through to mid/late autumn as the weather is suitable and timing won’t interfere with most farm practises

Is Lime good for stock?

• Because AgLime is completely natural, it’s fine for stock and actually makes the grass more palatable
• AgLime improves pasture quality and reduces the plant uptake of heavy metals from the soil, making the pasture more palatable
• When pasture is in good condition, animals will eat to appetite rather than just eat enough to meet their maintenance needs, which results in more production
• Research shows limed pasture is so appetising that stock will eat it to the ground before unlimed sections, when given the choice
• Better quality pasture is also very beneficial for nursing stock. Because of the highly nutritious pasture they are eating, the young stock they produce are in top condition

Caution is needed:

• Be aware of the risks of grazing dry cows in late pregnancy on recently limed pastures. AgLime can have a negative effect on cows in the transition period leading to calcium deficiency (milk-fever)
• How it works: Cows naturally defend themselves against milk-fever by mobilising calcium in their bodies. If pregnant dairy cows (springer’s) ingest calcium through lime particles still around on recently limed pastures pre-calving, the cow's metabolism tells it that it doesn't need to mobilise calcium as there is enough in its diet
• When the cow calves, without sufficient calcium to mobilise in its blood and may "fall over" with the condition hypocalcaemia or milk-fever. This is an Aglime induced calcium deficiency

Interesting AgLime Facts

• AgLime is one of the most versatile chemicals. In its various forms, lime is used in wonderfully diverse processes ranging from paper making to petrochemicals, rubber to recycling
• Most New Zealand limestone deposits formed in the Oligocene and Miocene periods, 5-37 million years ago, when the climate was warmer and much of New Zealand was submerged under shallow seas. Conditions were ideal for limestone formation. (Source: Teara.govt.nz)