Using Garden Lime
Adding Garden Lime to Your Soil
Adding Lime, a soil amendment material, to your garden soil will reduce the acidity of the soil by raising the pH level of the soil. The main reason for adding garden lime to your soil is to raise the pH level to ensure healthy growth and abundant crops for plants that do not grow well in acidic soils. When you raise the pH level, reducing acidity, this also has the benefit of increasing the availability of nutrients in the soil. It will also improve plants absorption of nutrients in the soil, meaning plants and flowers get more of the vital nutrients required for stronger, healthier growth. Adding lime to your soil will also improve the nitrogen availability and add calcium and magnesium to the soil. Plant nutrient uptake is directly linked to the pH level of the soil and therefore lime is vital for good, healthy growth and abundant crops. Lime will increase the levels of healthy soil bacteria and beneficial microbes thereby producing a healthier environment for plants to develop.
It is generally agreed that a pH level of 6.5 – 7 (Neutral) is a suitable soil for growing most plants, grasses and vegetables. Many plants and lawn grasses do prefer a soil with a pH level of between 6 and 7 though. Sometimes however the soil is acidic (too low – less than pH 6) or Alkaline (too high – higher than pH 7) and in these soils plants cannot not properly absorb vital nutrients from the soil. The plants will then develop nutrient deficiency.
To find out your soil pH level and whether or not you need to add lime you should test the soil using a pH tester. It is essential you check your soil pH levels in several different parts of the garden to gain an overall view of the levels in your soil. It is also good to know what pH level will best suit the flower or vegetable you intend to plant in each area of the garden. These soil testers are readily available in many garden centres and online stores and are reasonably cheap to buy. This one on amazon.co.uk is a good value price and tests acidity, moisture and light. Professional soil testing kit for checking soil pH levels. If this one is not suitable for your needs there is a wide range of soil testers available on amazon, ebay and other online stores.
You should also find out the type of soil you have in your garden. The soil type will determine how much lime you will need to add if you find that the pH level is not correct. You should know if the soil type is clay soil, sandy soil or loam soil before determining how much lime you will need to add. You can read more on soil types from the Royal Horticultural Society here: RHS soil types.
Using lime for your lawn
Most types of grass will grow in a slightly acidic soil, usually with a pH level between 6 and 7. If your pH level is below 5.8 then your grass is almost certainly doomed to struggle without intervention in the soil pH levels. Adding lime to lawns is an essential task in some soil types and in some parts of the country. Without the addition of lime then the grass will be unable to take benefit from nutrients in the soil. Adding fertilisers to your lawn will be a waste of time and money unless the pH level is changed to a favourable environment for the grass to flourish.
Which plants love lime and which loathe it
Before adding lime it is essential to know which plants will benefit from lime and which will hate it. Not all plants will flourish in the less acidic soil so it is very important to research and identify the plant’s natural habitat before adding lime to the soil. This task can be easily researched via printed media (yes, good old fashioned books) or by searching Google for the plant you wish to learn more about. A quick search will inform you as to the soil, and lime, preferences for each plant.
These are some plants which will benefit from adding lime to your soil to raise the pH level and increase nutrient uptake. Lime will be good for lawn grass, onions, garlic, parsnips, asparagus, broad beans, beans, soybeans, squash, cabbages, peas, spinach, rhubarb, cantaloupe, cauliflower, lettuce and other leafy vegetables. Apple trees and some other fruit trees will benefit from lime added to the soil. Lime will also be good for Lily of the valley, Phacelia, Ornamental clovers, Wild marjoram, Polemoniums, Sesleria caerulea, Lavender, Honeysuckle, delphiniums, buddleia and gypsophila.
You should never add lime to these plants as they prefer a slightly, or more, acidic soil. Do not add lime for sweet potatoes or regular potato crops, adding lime to these will destroy your crop. You would also be advised to avoid adding lime for tomatoes or capsicums. A lot of berries also prefer a more acidic soil so never add lime to crops of especially blueberries, strawberries and raspberries.
When to Add Garden Lime to Your Soil
Garden lime is generally applied to the soil in either spring or autumn. It is up to individual gardeners to decide which is best for their needs, and their gardens, when deciding which time of year to add the lime.
Most gardeners will apply lime in autumn as this will give the soil more time to fully absorb the lime and give it the necessary time required to get to work on the soil to change the pH levels. The more time you give the lime to work the better it will be for the soil. Adding lime will not change pH levels immediately so it will need several weeks, and possibly months, to change the pH levels to the optimum level. Giving lime more time to work on the soil will increase the levels of lime nutrients in the soil before planting.
You can also add lime in the spring but in this instance you will have to apply in early spring and give the lime several weeks to work before planting. You should plan to give lime at least 4 weeks to work on the soil.
How Much Lime Should You Add to Your Soil
If you have determined soil type and the current pH level from a tester you are now ready to proceed to add lime to your soil. Most flowers and vegetables will prefer a pH level of 6 to 7. To calculate how much lime to add to increase the pH level use the table below based on your soil type.
This table is designed to show how much lime you will need to add to your garden for a 1 METRE SQUARE AREA to raise pH level to around 6.5 – 6.7 which is suitable for most gardens and plants. Calculate the full garden area you need to apply lime to, then multiply to find out how much lime you will need for the whole area you need to treat. Using these rates should bring the pH level to its optimum balance of between 6.5 and 6.7.
|Your Soil Type||pH Tester Reading||Lime Required 1M Sq|
|Clay Soil Type||5.0||1.4 KG|
|Clay Soil Type||5.5||1 KG|
|Clay Soil Type||6.0||600 GRAMS|
|Sandy Soil Type||5.0||1 KG|
|Sandy Soil Type||5.5||700 GRAMS|
|Sandy Soil Type||6.0||400 GRAMS|
|Loam Soil Type||5.0||1.2 KG|
|Loam Soil Type||5.5||800 GRAMS|
|Loam Soil Type||6.0||500 GRAMS|
Different Types of Lime: Powdered, Granular and Aglime
Basically all these types of lime do the exact same job, they increase the pH level of the soil. Aglime (agricultural lime) and powdered lime are both a fine powder made from crushed limestone. The granular or pelletised (pelletized) lime is made from granulating the powdered lime and bonding it with lignosulfonates.
In general it is accepted that the granular lime version is best for gardens for two reasons. Firstly, it can be applied by spreader, or by hand, without the dust blowing everywhere, meaning you get your application accurately into the target area. Powdered lime is dusty and can blow around on areas that you don’t want to add lime to, it can also blow into your face and mouth and this is not pleasant, nor healthy. Applying powdered lime can be challenging and the application can be downright messy and ineffective. Secondly, granular lime does not always have to be tilled into the soil, which is handy for applying lime to your lawn or plant areas when you don’t want to dig the whole area or lawn up. You can just spread granular lime on the surface, it is simple to distribute, and then just add water to activate it and you are done, quick and easy. You should note that you will need to add around 1cm-2cm of water to areas treated with palletized or granular lime. Granular lime is easy to distribute, therefore, for many homeowners and keen domestic gardeners, it requires very little expense in regard to tools or machinery to apply it.
How to Add Lime to Your Soil
Using Pelletised or Granular Lime
Once you have worked out which type of soil, clay, sandy or loam, you have in your garden and then calculated the amount of lime you will need to apply to cover the entire area it is time to proceed with the application. Spread the required amount of lime across the surface of the garden area to be treated. For an example of the rate to use we will take the Clay Soil Type with a pH reading of 5.0. You will need to evenly spread 1.4 KG over each 1 metre square area to raise the pH level to around 6.5 – 6.7.
At this stage you can till the lime into the soil to a depth of around 8 inches (20cm) for best results. The granular lime will act quicker if tilled into the soil. It is not a necessity to till granular lime into the soil though, it can be left as it was spread on top of the soil. This is a handy application for a lawn where you can’t, or don’t want to, dig the whole lawn up. If tilling granular lime into the soil isn’t required then all you really need to do is water the treated area so that the lime cannot burn the soil, apply around 2cm – 3cm water to the area and that is the job done. Using pelletised or granular lime it is a matter of spreading lime around the lawn, plants or trees and then watering. As simple as that.
The final step is to get on with other tasks, or just take it easy. Give the lime time to get to work. It is best if the lime is applied in the autumn so it has plenty of time to work. If that isn’t possible you can still apply lime in spring. If applied in spring try to give lime at least 4 weeks before planting. If you have applied the lime in autumn then you can continue testing the soil every so often to see how the pH level is responding to treatment.
Using Powdered Lime
Now you worked out your soil type and how much lime you need to add to the soil it is time to go ahead and get that lime into the soil so it can get to work. You should dress suitably for this job. It would be preferable to apply powdered lime whilst wearing gloves, mask and protective or old clothing, as this lime is very dusty and blows easily in the wind. Inhaling or swallowing lime is not pleasant and it can possibly cause illness if high amounts are ingested. Although studies show lime is non-toxic to humans and pets it is best to be careful.
Spread the required amount of lime across the surface of the garden area to be treated. For example for Clay Soil Type with pH reading of 5.0 you will need to evenly spread 1.4 KG over each 1 metre square area. Once you have spread the required amount of lime evenly over the surface you should then proceed to till it into the soil. Using a shovel dig the soil down to typical root levels between 8-12 inches (20cm – 30cm) depth and then till the lime into the ground. The powdered lime will not be effective if left applied to the top of the soil. The lime must be tilled down into the soil to a depth of around 8 inches (20cm) so it can take effect and change the pH levels and provide required nutrients for the plants.
After you have applied the lime and tilled it into the soil where it can work to best effect it is time to water the lime. Water is a necessity to activate the lime you have added to the soil. Ensure to give the treated area a good watering to soak the soil and get the best results from the lime.
Now that you have applied the lime you must give it time to work. Do not plant or seed for at least 4 weeks. This is why autumn is the best time for applying lime, it gives the soil time to react to the lime and be ready for planting in the spring. If this isn’t possible then do it early spring and hold off planting as long as possible. Adding lime in the autumn also allows time for testing the soil again in the spring to check that the optimum pH level has been achieved.
Warnings and Care When Using Lime
Take care that you are not using burnt lime, hydrated lime or builders lime. These are known to be caustic and should only be used with extreme caution. These caustic limes can be harmful to humans and pets.
Dolomitic powdered and granular lime are non-toxic and generally regarded as being safe for humans, pets, birds and wildlife. However, I would recommend keeping pets off treated areas for a few days, it is slightly possible the lime may irritate paws.
When applying lime wear gloves and masks, especially if working with powdered lime.
Always water the soil well so that the lime is well activated and so that it does not burn the soil.
Do your research on the plants before adding lime. Check how neighbouring plants will react if lime gets into the soil of these areas. Only add lime if your plants require a less acidic soil.
If you require granular garden lime to change the soil pH level of your garden soil then check out our options in our online shop iron sulphate here. You can also order our garden lime from our Amazon.co.uk store here.