What's the seasonal fertilization schedule?
Written by
Julia Anderson
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Good fertilization is done during a seasonal cycle, which follows the growth habits and patterns of grasses. Cool-season species need to be fed in the spring and fall. At the same time, warm-season grasses often utilize fertilizer applied in late spring and early summer. You should always construct your fertilization schedule based on soil testing rather than guesswork. I use this practice to achieve lush turf without waste.
Spring Application
- Apply slow-release nitrogen after second mowing when soil warms
- Use 0.5-1 pound per 1,000 square feet maximum
- Choose formulas with iron for greening without excessive growth
Fall Preparation
- Feed cool-season grasses potassium-rich fertilizer before first frost
- Apply 6-8 weeks before ground freezes for root storage
- Avoid high nitrogen preventing tender growth vulnerable to cold
Utilize slow-release formulas to reduce the potential for burning/losing nutrients. These will release nutrients to the grass slowly over a period of 8-12 weeks. During hot weather, above 85°F, it is best to avoid using quick-release synthetics, as they can potentially harm the roots. I switched to using polymer-coated nitrogen and had better-looking turf.
Conduct soil tests every two to three years. Multiple lawn areas, with a depth of at least 4 inches, should be used when collecting the soil. Soil tests identify deficiencies and excesses, preventing unnecessary applications of fertilizers. If your soil is deficient in phosphorus, add bone meal. If the pH is high, you will need to make adjustments with elemental sulfur.
Adjust to local conditions. For Northern turf, fertilize when forsythia is blooming in the spring. For Southern grasses, apply fertilizer when the soil temperature reaches 65°F. Drop spreaders are the best way to achieve a precise application along edges. Annual calibration of your equipment is crucial; otherwise, you will obtain inaccurate coverage, and the already covered area won't burn due to overlap.
Once the lawn has been fertilized, remember to water it thoroughly so the nutrients can move into the root zone. Generally, we apply 0.25 inches of water, unless we are dealing with moisture-activated products. Do not fertilize during a drought or heat wave. This seasonal approach enables us to establish resilient turf that requires less maintenance over the long haul.
Read the full article: How to Care for Lawn: Beginner's Guide
