Need fertilizer recommended by soil test report

[Janetrob 0]

Hello. I had a soil report done last fall. They are recommending three fertilizer types: 12-0-42 or 5-0-15 or 0.7-0-2. I did a quick search online hoping to find a retail location to find it. That wasn't very helpful

I am willing to visit Home Depot, Lowes or anywhere else I need to but wondered if what I'm looking for exists in this formulation or where might be the best place to get this. I haven't done this before. I appreciate any help you can give me!

[Janetrob 0]

I wanted to update my question. Since posting it I talked to some garden center staff and have gotten educated (shout out for learned and experienced employees willing to share their knowledge . I now understand that getting a prescribed fertilizer ratio off the shelf isn't usually going to be possible. I will be using potash and adjusting for the percentage based on the report. I was told that nitrogen, the other recommended nutrient, changes easily and could already be different than in the report. It was suggested I add it separately later. Thanks!

[Janet Macunovich 32]

So sorry we were so slow to get here but brava for your research and solution!

 

You don't need this, then, but for others who might not find such good guidance as you received:

 

Basically what your soil analysis indicated was a need for some nitrogen (about half the plant's annual needs), no phosphorus and between 3 and 4 times as much potassium as nitrogen. 1-0-3.5  Any fertilizer with that ratio, including 2-0-7, 4-0-14 or 12-0-40, will do the same. However, those good people you talked to are right on - you usually have to create your own mix.

 

Use the ingredients label and the math most of us gardeners would like to avoid to figure this way:

 

An average amount of nitrogen (N) in garden soil is 2 pounds in 1,000 square feet.

 

The numbers on a fertilizer label are percent of a nutrient by weight. N is first, then phosphorus (P) then potassium (K).

 

So a 500 square foot garden needs about 1 pound of nitrogen (N).

 

10 pounds of blood meal 13-0-0 supplies 1.3 pounds of nitrogen - 10 pounds x 13% = 1.3.

 

Since the soil test says your garden has half its needs - needs only a 1% N fertilizer - 500 square feet of your garden needs only 1/2 pound of N. 1.3 pounds of N is enough for about 500 square feet of garden for a year.  5 pounds of blood meal per 500 square feet is good for your garden: 5 x 13% = 0.65. More is not a problem if it is an organic fertilizer like blood meal (carbon-based compounds like blood meal don't "burn" like a water soluble form such as a blue powder).

 

Since your garden needs 3 times as much potassium as nitrogen, you need 1.5 pounds of potassium for 500 square feet. 5 pounds of muriate of potash 0-0-60 supplies 3 pounds of potassium - 5 x 60% = 3. So 5 pounds of muriate of potash will last you two years.