Potassium - Ask Extension
Potassium level very low. A 12-12-12 fertilizer is recommended for spring planting and it suggests potassium be added in the fall. It would seem it wo...
Knowledgebase
Potassium #929043
Asked April 20, 2026, 9:14 PM EDT
Potassium level very low. A 12-12-12 fertilizer is recommended for spring planting and it suggests potassium be added in the fall. It would seem it would be helpful to add potassium now for the spring planting??? It is a small garden, roughly 250 square feet and the soil I’d very sandy. Your advice will be most appreciated.
Berrien County Michigan
Expert Response
Hello
The 12-12-12 fertilizer recommended is 12 percent potassium, indicted by the 3 rd number in the “12-12-12. So, you will be adding some potassium when you apply it this spring.
Each number on the label of fertilizer stands for the percent of the major nutrients it contains, and always in this order— nitrogen, phosphorus, potassium. That is the “N-P-K” . If you would like to read more here is a bulletin- https://extension.oregonstate.edu/gardening/techniques/guide-understanding-fertilizers
Please follow your fertilizer label for all the precautions and directions for that product’s use. Then use your soil test report to determine how much to apply and when.
The 12-12-12 fertilizer recommended is 12 percent potassium, indicted by the 3 rd number in the “12-12-12. So, you will be adding some potassium when you apply it this spring.
Each number on the label of fertilizer stands for the percent of the major nutrients it contains, and always in this order— nitrogen, phosphorus, potassium. That is the “N-P-K” . If you would like to read more here is a bulletin- https://extension.oregonstate.edu/gardening/techniques/guide-understanding-fertilizers
Please follow your fertilizer label for all the precautions and directions for that product’s use. Then use your soil test report to determine how much to apply and when.
