Knowledgebase
Bar graph question #948186
Asked November 06, 2026, 12:45 PM EST
Oakland County Michigan
Expert Response
Hello Heather,
Knowing the make-up of one's garden soil and following the personalized recommendations provided from a soil test is a smart step for successful gardening. Kudos to you for taking this step.
Your soil test shows on the bar graph, that levels of Phosphorus, Potassium and Magnesium are all Above Optimum, indicating that there are sufficient amounts of these nutrients to sustain healthy plant growth. This is very likely due to the healthy level (9%) of organic matter in your soil.
Adding mulched leaves this fall, as you suggest, will be a good step in maintaining the organic content. However, I would discourage you from adding nitrogen until the Spring.
I recommend you look at the Must Read Tip Sheets listed next to the Follow Your Personalized Recommendations. One sheet in particular,
Fertilizing Annual Flowers and Ornamental Vegetables explains that fertilizing products vary in their length of availability to the plant, usually 3 to 6 months, so applying nitrogen now would not be available to your flowers in the spring.
Zinnias, dahlias and cosmos are all beautiful plants providing wonderful color in your all summer long. The Fertilizer Basics tipsheet provides guidance on fertilizer selections. Please let me know if you have any further questions.
Hello Heather,
Knowing the make-up of one's garden soil and following the personalized recommendations provided from a soil test is a smart step for successful gardening. Kudos to you for taking this step.
Your soil test shows on the bar graph, that levels of Phosphorus, Potassium and Magnesium are all Above Optimum, indicating that there are sufficient amounts of these nutrients to sustain healthy plant growth. This is very likely due to the healthy level (9%) of organic matter in your soil.
Adding mulched leaves this fall, as you suggest, will be a good step in maintaining the organic content. However, I would discourage you from adding nitrogen until the Spring.
I recommend you look at the Must Read Tip Sheets listed next to the Follow Your Personalized Recommendations. One sheet in particular,
Fertilizing Annual Flowers and Ornamental Vegetables explains that fertilizing products vary in their length of availability to the plant, usually 3 to 6 months, so applying nitrogen now would not be available to your flowers in the spring.
Zinnias, dahlias and cosmos are all beautiful plants providing wonderful color in your all summer long. The Fertilizer Basics tipsheet provides guidance on fertilizer selections. Please let me know if you have any further questions.