Spring lawn feeding (high nitrogen)

When

Feed once the grass has started growing again, usually from mid-March to mid-April in a continental climate, around the time of the first mow of spring. Feeding earlier, onto cold soil or a frozen lawn, wastes the fertilizer: roots are not taking it up yet and rain washes it away.

What and how much

Use a spring lawn fertilizer high in nitrogen, such as NPK 20-5-8, at 25–30 g/m² (about 5–6 lb of product per 1,000 sq ft). At that rate a 20-5-8 product supplies roughly 5–6 g of nitrogen per square meter, about 1 lb per 1,000 sq ft, which is a full single feed. Follow the rate on your product's label if it differs.

Spreading it evenly

• Use a spreader rather than throwing it by hand; hand spreading leaves dark green stripes and scorched spots.
• Split the amount and make two passes at right angles.
• Apply to dry grass when light rain is forecast, or water it in, so granules do not sit on the leaves.
• Sweep any granules off paving; fertilizers containing iron stain stone.

Do not overdo it

More nitrogen than this in one go gives soft, fast growth that needs mowing constantly and is prone to disease. The next feed comes in early summer, at a lower and slower-release dose.