The frequency of fertilizing your lawn depends on factors such as grass type, climate, and fertilizer type, but general guidelines are as follows:

• Cool-season grasses (common in northern climates like Ontario) typically benefit from fertilization twice a year : once in spring and once in fall. Spring fertilization supports leaf growth, while fall fertilization strengthens roots before winter

• Warm-season grasses are usually fertilized about three to four times a year , starting after the last frost and continuing through summer and early fall

• Some experts recommend fertilizing three times a year (spring, summer, and autumn) for general lawn health, but if you fertilize only once, spring is the best time

• For established lawns, a common rule of thumb is to fertilize every 4 to 6 weeks during the growing season (when temperatures are moderate), but this may be excessive for typical home lawns and more suited to intensive care like golf courses

• Over-fertilizing can damage grass roots and cause scorching, so many lawn care professionals advise not fertilizing more than twice a year for most home lawns to avoid harm

• Using a slow-release fertilizer and following label instructions is important. The total amount of nitrogen applied per season matters more than frequency

• A practical schedule some recommend is applying fertilizer every 8-10 weeks during the growing season, often aligned with holidays for ease of remembering

Summary Recommendation for Home Lawns:

• Fertilize 2 to 3 times per year for most lawns.
• For cool-season grass: once in spring after growth begins, once in fall before frost.
• For warm-season grass: start about six weeks after last frost, then mid-summer, and possibly early fall.
• Avoid fertilizing in the heat of summer for cool-season grasses.
• Always follow fertilizer package instructions and consider a soil test to tailor fertilization.

This approach balances lawn health and avoids risks of over-fertilization