Browse by Category
Mag-I-Cal® for Lawns in Acidic Soil
- One bag of Mag-I-Cal® has the pH adjusting power of up to 15 bags of limestone
- Rapidly and efficiently raises soil pH
- Calcium and humates balance soil pH and stimulate microbial life
- Encourages nutrient absorption
- Spreader Settings
- Product Label
- Reviews (47)
Jonathan Green’s Mag-I-Cal® for Lawns in Acidic Soil contains calcium carbonate in a completely soluble form that is immediately available to adjust soil pH upwards. Poor soil is often the problem in growing a great lawn and calcium is vital to many grass plant functions.
Lawns thrive in soil with pH levels between 6.2 and 7.0. When the pH level of the soil is below this range grass becomes light green, weeds persist, and fertilizer nutrients are not fully absorbed. Mag-I-Cal® Plus also contains humates to stimulate soil microbial life. When soil chemistry and biology are balanced, nutrients from lawn foods are not wasted and the grass will thrive.
When to Apply:
- Best applied during the growing season when the soil is not frozen.
- Safe to apply when seeding or sodding.
- Spread the product on a dry lawn soon after mowing.
- For best results, rake the lawn vigorously prior to application.
- Use a rotary or drop lawn spreader. To select the proper setting see the Spreader Settings section in the accordion below.
- Apply around the perimeter of the lawn to establish a turning area. Then run the spreader back and forth within the area outlined by your first perimeter application. Always allow overlap to avoid gaps in coverage.
- Can be used on vegetable gardens.
- To avoid staining, sweep any excess granules off of hard surfaces and back onto the lawn.
- Irrigate the treated area after application for 15 – 30 minutes for the best results.
- Once watered, wait a day to mow the lawn to give the product time to activate.
- For soils with pH lower than 6, repeat applications twice a year.
- 3.6 lb Bag – 1,000 sq. ft.
- 18 lb Bag – 5,000 sq. ft.
- 54 lb Bag – 15,000 sq. ft.
Fortified With: Soluble calcium
Can Be Used When Seeding: Yes
Apply to Dry or Damp Lawn: Dry
Safe for Children & Pets: Yes
Application Temperature Range: Minimum 45°F
When to Use: Spring, summer or fall
The spreader settings listed are approximate. Spreader condition, rate of walk, and humidity are just some of the variables that can affect the rate of application. Please refer to the product label link on this page, or the back of the bag, for further details along with application rates and precautionary statements. You may need to adjust settings for proper coverage if circumstances described on the label are applicable. In all cases, the user should read and follow label instructions before applying any product, and assumes all responsibility when using this spreader settings tool.
Click the button below to view and download a pdf of the product label.
Talk about Magic..My lawn was in very poor shape…after plenty or research on how to use Johnathen green products guess what? Every lawn needs magical period…i tested it and the areas without magical barely filled in even after using green up and jg weed and feed…and water…very slow growth
.but after the magical OMG the lawn started filling in full and Thick…..my lawn went from poor to one of the best lawns in town…
Great stuff works fast. I’m a lawn nut it help my PH in my soil
My yard (formerly a farm field of heavy clay soil) had a horrible problem with bare spots, spotted spurge and other, less prolific, weeds. Checking the soil pH I found it was very low. Over late winter and again in early spring I applied Mag-i-cal and Love Your Soil; this summer the overall situation was MUCH better. Significantly less spurge (yes, there was still some but it was significantly less rampant), fewer bare spots and an overall healthier lawn, that came back beautifully after the long, stressful dry summer spell. Was it the Mag-i-cal? The Love Your Soil? Who knows. The science says it should have helped so I will be applying it again this year!
The scale I received works well. I don’t need a super high degree of accuracy, within a tenth of a gram is fine with me. I test it with U.S. quarters each time I use it, and it has been consistent. It’s a perfect size for me, not too small, and the weight info is very readable. I would buy this again knowing what I know about how mine has worked thus far.
Just spread this 1 day ago. Stay tuned for results
just bought more great product
Fantastic product and my lawn looked great after use. Very easy to use, specially if you have a broadcaster, if not buy one as it will really cut down your spreading time and broadcast evenly. Everyone should use this product. Recommended!
Easy to use—plants/fruit trees doing great after putting this down. Apples look healthier.
This product gave my grass the nourishment that it needs, it takes a while to see the results but the waiting is worth it.
Applied to lawns at my previous house for sale and the lawns at my new home’s lawns. Wow, what a diffence it made to both properties! Highly recommend.
This stuff seems great. I did not test the pH of my soil prior to application, but I did test it recently and it is in the ideal range for grass. I applied maybe 6 weeks before testing? But not for any reason or anything. I just came across a Jonathan Green pH tester at my local garden center and decided to give it a shot.
The nice thing about this product is that it looks like dirt. This was nice because it meant my dog wasn’t going to mess with it, and she didn’t.
Used before reseeding the lawn. Seems to have helped with some compacted soil. Grass has now grown in and is looking good
Good stuff. I put it down and my grass is now green and has a blue tint to it. I think it is good.
I left a long winded explanation on the Jonathan Green fertilizer. The short version: I’m obsessed with my lawn. I used to pay crazy money to have various pro’s do it. Then I spent a few years doing it myself. This brand is just unbelievable. My beautiful Kentucky Bluegrass has never looked healthier. The only negative: I have to cut the lawn more often now. That pretty much sums up this line of products. It’s worth every penny, and then some.
the stars speak for them self.
Make the grass a beautiful green and prevents weeds. Makes the soil soft so it can hold water. I put it on packed down dirt in a high traffic area and the dirt became soft and the grass grew thicker.
Plants are greening up. Easy to apply. Glad it works so well!!
I was thinking 10,000 square feet was a lot of space. I got three sections of my yard covered. I am gonna have to get another bag when I have a chance.
Works well on “tired” lawns. Provides much need to boost to the soil for over seeding . Defiantly works and will be a part of my yearly lawn maint going forward.
Seemed good. I measured Ph levels before and after application and after one application the level was around 6.5, which, according to Jonathan Green, is excellent. However, I have yet to see an actual improvement in the lawn. I expect that this will take time.
Great stuff! This is just one of the ingredients in the super soil I compost. Best tomatoes in town!
This stuff is amazing. It really makes the grass look rich and green. Suggest a spring and fall application.
This is some good stuff. First time I ever used it was a month back and due to mild temps my grass is looking pretty good even this time of year. I like that it has the calcium also it help !
It works great as a fertilizer, but it also repels rabbits form chewing off my flowers. Not much more I can say about it.
Grass looks great
I applied this around the middle of April 2015 and my grass is greener and thicker than any of the other lawns in my neighborhood! !!!!! I will be reapplying around the middle of August 2015 !!!!! I will post any changes if I see any !!!!!!!! I recommend all Johnathan Green products to all my friends and neighbors. I freshly planted my yard April 2015 and my neighbor who moved in next door to me works on a sod farm and asked me what sod I had used and I told him I prepared and planted my yard with Jonathan Green products and Black Beauty seed and it is almost 3 months later and he thought I used sod.
I don’t know why this works, but when paired with their seed, you really get thick grass pretty quickly, without constant watering.
Nothing gets my lawn greener, quicker.
Put this down before the snow hit our area, and seeded, should look good in the spring. ..
a MUCH NEEDED item for Garden 2015 ( it is ready to be tilled one final time and be planted )
I overseeded my lawn last fall and was disappointed in my grass all season this year. A month ago I used mag I cal with love your soil love your lawn and green up. All jonathan green products while everyone’s grass is going dormant mine is getting greener and greener and growing. Big fan of Jonathan Green
It is a miracle it really saves on the cost of other products
It’s a good buy. I don’t know how long it will take for a difference to show up in my yard.
TOTALLY SATISIFIED. BEST PRODUCT!!!
Have not used it yet. But I anticipate it will do a fantastic job like many of the other products I’ve used so far, like the summer fertilizer, spring crabgrass pre-emergent, winterize fertilizer. All have worked as advertised for a north eastern lawn.
Very concentrated soil conditioner, my lawn looks great since I started using this product. I have pine trees around my front yard and this product helps to neutralize the soil.
Much more effective than traditional lime and thus worth the price. Lasts several months even under acidic trees like spruce.
Used this along with Jonathan Green Grass seed. I am not a green thumber or a landscaper, so I really can’t comment if this made a difference. Grass did grow, and it grew well, so for all intensive purposes I will attribute that fast growth to this product. Would I recommend this? Yes. Works well, and covers a large area.
Your lawn, plants, trees, will love it; it will maintain water in your plants, lawn and trees for less water.
This product does green up your lawn. My lawn has never looked this good. It works much better than lime and my lawn got compliments.
The company needs to do a better job with the instructions, though. This small bag had no application instructions for this bag size, leaving me to guess how to apply it.
I took a sample of my soil in to the local tractor supply/farm store to check my Ph levels. Turns out my soil is around 5.0. When I asked what I could do to raise it up to the recommended values of 6.5 to 7 the person told me to put down lime. I gave her a rough estimate of my lawn size and she said it would take 40 bags of 40 lb Lime. Not only would transporting it be an issue, but the thought of hauling it across my lawn made my back hurt. I saw this nearby and considered purchasing it but decided I would wait.
Fast forward a year and I talk to another salesperson at a local Ace. He tells me all sorts of things, including how this is equivalent to 10 bags of the 40 lb lime (for the 45 pound size) and actually lasts longer. After wondering why the previous person didn’t tell me this information, I went ahead and purchased my bags.
The fact that 1 bag = 10 of lime makes it totally worth it in my mind. Add in the fact that the price is roughly the same, if not cheaper, and this looks like a better and better deal.
After a long drought of a summer my grass looked like it was gone. There were dead spots all over, it was crisp and fragile. Prior to this I had a beautiful lawn, it was weed free, always green. After aerating the lawn and pulling up some of the dead thatch in the dead spots I put this Mag-I-Cal down with Jonathan Green Ultra Black Beauty grass seed as well as Jonathan Green Fertilizer. Within 2 weeks I had the greenest grass on the block, new grass was appearing and it was soft to the touch. Now after a few months its been a mild winter but it’s still green and the greenest around. I’m defiantly a believer and will continue to use this every year. Worth the price!
Frequently Bought Together
4.847619047619 out of 5
Black Beauty® Original Grass SeedJonathan Green's most heat & drought tolerant grass seed blend.
4.7363636363636 out of 5
Black Beauty® Shady Nooks Grass SeedSurvives in wet or dry areas of up to 90% deep shade where other grasses fail.
4.5555555555556 out of 5
Green-Up Fertilizer for Seeding & SoddingLawn Food for use on newly planted seed & sod producing healthy, deep roots.
4.75 out of 5
Soil pH Test KitEasy to use kit that quickly determines soil pH. Get results in only 10 minutes!