Choosing Espoma for Organic Soil Supplements

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No one worked the soil on our farm for five years. The front four acres were used to grow soybeans, when we bought the land they were covered in overgrown brush.

The soil looked gray, lifeless, dead.

When I decided to start growing organic vegetables there, I knew that I’ll need to add some supplement to it.

Choosing Espoma Organic Soil Supplements

But the world of organic soil supplements can be a little intimidating. In the beginning, I was completely overwhelmed with all the options and a bit lost as to what to choose.

Let me share with you the results of my research…

Why Should I Add Organic Supplements to My Soil?

My first question was why. Why should I bother with soil supplements? Why should I spend all this money? Is it really necessary?

The crew at Espoma put this wonderful video together, I couldn’t explain it better…

So now we know that the three most important nutrients we have to pay attention to are…

  1. Nitrogen (N) – For plant growth.
  2. Phosphorus (P) – For root development and flowering.
  3. Potassium (K) – To make plants hardier and disease resistant.

What’s My Soil Missing?

Obviously, you can’t just look at your soil and see that there is not enough phosphorus in it. You’ll need the help of a lab.

Thankfully, you can collect soil samples and send them to the lab through your county’s cooperative extension (it’s a free service in most counties).

Make sure to take different samples for different areas in the garden and label them. Blueberries need acidic soil for good growth while vegetables need somewhat neutral pH for better growth. You should take one soil sample for the blueberry patch and another for the vegetable patch since you will probably need to amend them differently.

It takes two to three weeks until you get a report from the lab. Make sure to send it early to give yourself enough time to prepare your garden for planting since it’s better to add the supplements before planting than after.


Above is an example of the report the extension will email you (you can click the image to view it a bit larger).

Now let’s see what is going on with my precious soil here. First, make sure this is your report, it’s not going to do you any good reading your neighbor’s soil report.

You can also see on the right side in the middle it says “Soil ID: VEG.” I sent two samples and named one VEG for the vegetable patch and BERRY for where I wanted to plant blueberries. Make sure you know which area of your garden you are looking at.

Soil test results for vegetable garden area:

pH – My soil pH is 6.5 which is good since optimum soil pH for most vegetables is between 5.8 and 6.5. This means that I don’t need to add lime to my soil. Adding lime will make it more alkaline which is not very good for most veggies.

Phosphorus – 35, or in other words way too low. The optimum here is between 50-70. So I will have to add Phosphorus.

Potassium – 72. Slightly higher than the optimum at 50-70. I do not need to add Potassium.

As you can see, the test does not measure nitrogen (N) levels. The reason is that nitrogen levels are very unstable in soils. What they recommend is to add nitrogen anyway if you can.

Choosing Organic Soil Supplements:

After much reading and research, I chose to purchase Espoma supplements.They are organic, safe to use around pets and kids, made in the US, and they are actual rock, not liquid so they will release into the soil over time.

I will repeat the soil test next year, but from what I’ve read it sounds like I will have to add those every few years (4 or so), which makes it a good investment.

Gypsum – since my soil pH is 6.5 I shouldn’t use lime as a soil conditioner. Lime will increase my pH further, making my soil alkaline which is not great for vegetables.

So instead of lime, I chose gypsum. It is meant to improve the soil structure, just like lime, but it doesn’t affect the pH levels in the soil. It is also great for breaking clay soil, helping your soil to become softer and easier for the plants to grow on.

Choosing Organic Soil Supplements - Lady Lee's Home

This is what’s inside the bag, a pelletized material for making application easier.

Rock Phosphate – since my Phosphorus level is super low, I needed some rock phosphate. Remember, phosphorus helps plants develop strong and healthy roots. Strong and healthy roots mean better support for your plants and ease in finding and absorbing water and other nutrients from the soil.

Choosing Organic Soil Supplements - Lady Lee's Home

Phosphorus looks much like gypsum, just a bit darker. It’s also pelletized for easy application.

Greensand – this is another soil conditioner which has many many minerals in it like potassium and trace elements from natural marine deposits. It helps grow healthy and strong plants.

Choosing Organic Soil Supplements - Lady Lee's Home

Looks just like its name, green sand.

How to Apply Organic Soil Supplements?

Gypsum, Greensand and Rock Phosphorus need to be applied at time of planting.

Gypsum – 1 lb = 1 3/4 cups. Apply 6 lb per 30 sq ft. Mix into top 6 inches of soil.

Rock Phosphate – 1 lb = 2 cups. Apply 5 lb per 100 sq ft. Spread on top of the soil.

Greensand – 1 lb = 1 1/3 cups. Apply 5 lb per 100 sq ft. (10 lb per 100 sq ft for medium application and 30 lb per 100 sq ft for heavy application). Spread on top of the soil.

Choosing Organic Soil Supplements - Lady Lee's Home

Here is an example of two beds in our farm. They are 30” wide and 30′ long with a 20” walkway in between.

The Process

  1. Clean the bed of old plants, weeds, and rocks.
  2. Till (if it’s a new bed or if the soil is too compacted).
  3. Apply gypsum and compost.
  4. Till or mix (with a rake) the top 6 inches of the soil.
  5. Apply rock phosphate and greensand.
  6. Sow your seeds.

How Much to Apply?

This is a great time to use your child’s young, fresh mind. If you don’t have a child handy, borrow the neighbor’s. If the neighbor doesn’t have a child, you’ll have to figure this out yourself. Just try not to curse yourself too hard for day dreaming during math class in 6th grade. We all had much more important things to do in 6th grade than math!

Anyway, 30” are 2.6 feet. 2.6 feet times 30 feet = 78 square feet.

Gypsum –  (1 lb = 1 3/4 cups. Apply 6 lb per 30 sq ft). Let’s convert from lb to cups. Since every 1 lb of gypsum = 1 3/4 cups, 6 lb of gypsum = 10.5 cups (1.75 x 6). So now I know that I need to apply 10.5 cups per 30 sq ft.  But each of my beds is 78 sq ft. So let’s divide 78 to 30 = 2.6, now we can multiply 2.6 x 10.5 = 27.3. I need to apply 27.3 cups of gypsum per bed.

Rock Phosphate – (1 lb = 2 cups. Apply 5 lb per 100 sq ft). Again, let’s convert 5 lb to cups. 1 lb of phosphate = 2 cups, so 5 lb = 10 cups (5 x 2). So we need to apply 10 cups per 100 sq ft. Let’s divide 78 to 100 = 0.78 x 10 cups = 7.8 cups. Let’s round up and say I need to apply 8 cups of phosphate per bed.

Greensand – (1 lb = 1 1/3 cups. Apply 5 lb per 100 sq ft for light application). Again, converting lb to cups first. 1 lb of greensand = 1.33 cups, so 5 lb = 6.65 cups (5 x 1.33). This means we need 6.65 cups per 100 sq ft. Let’s divide 78 to 100 =0.78 x 6.65 cups = 5.19. Let’s round down and say that I need to apply 5 cups of greensand per bed.

I am no math teacher, but I hope you understand the calculation (if I made any mistakes, please let me know).

Espoma’s products are safe around kids and pets, approved for organic gardening and are pure products. They will help you grow healthy plants with fewer pest problems.

I presented only three of their products here, but they have many more. Their line of products covers anything from seed starting to lawns, tomato plant feeding, supplements for flowers and many more. You can find more information on the Espoma website, and you can find their products for sale on Amazon.

Choosing Organic Soil Supplements

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6 thoughts on “Choosing Espoma for Organic Soil Supplements”

  1. Ugh! I really wanted to have our soil tested last year – but procrastinated….
    This will be our second year on our land here, and we live in a river valley with incredibly rich soil. Our garden was amazing last year – incredible roots, growth, and vegetable production. So much better than the hard red clay where we used to live.

    This is great information, because this year I DEFINITELY plan to test our soil. I want to keep it healthy to enjoy many years of good production. Plus we will be planting blueberries and want to start preparing the soil for the berry patch (adjusting the ph).

    Anyway, my question is, when do generally do your soil testing – spring or fall? I have heard it doesn’t matter as long as you are consistent from one year to the next. Also, is there a waiting period between application of the amendments you mentioned, and planting? I was thinking fall would be best (for me), to allow time to amend the soil and have cover crops over the winter (we take a break during the winter).
    Thanks for the information (and inspiration – no procrastinating this year)

    1. It really doesn’t matter when you do the soil testing. You can do it in the spring but you need to make sure you are going to get it back before planting time so you have time to amend. You can amend and plant right away, at least with Espoma it’s this way.
      I think your plan is great, test in the fall before you are ready to put your garden to bed. Then add amendments and plant with cover crops or cover with a thick layer of mulch. If you mulch, I wouldn’t touch the soil in the spring, just plant. If you plant cover crops you have to till them under 3-4 weeks before planting time so they have time to break down.
      Also, you don’t need to test every year. Those amendments above, if you add the right amount, should keep your soil great for 4 years. Testing every few years should be enough.
      For blueberries, you definitely want to test in the fall. I am going to guess that your pH is somewhere between 6-7. It needs to be lower for blueberries and it takes time to change. So you want to make sure you amend in the fall, then plant the following spring. There are pH testing kits that you can buy for just a few dollars if you want to check the soil again in the spring before planting. And Espoma has a blueberry amendment too.
      Good luck! I’ll start following your site and look for updates on the garden. Thanks for visiting!

  2. thanks so much for sharing have decided this is the year to follow in the path of past generations of the family who used the land to take care of their families
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  3. What great information. We’ve never supplemented our soil with a purchased product, we just add compost. I should probably have the soil tested to see how it’s doing. 😉 Thanks for sharing at Simple Lives Thursday; we hope to see you again this week.

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