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Garden

When to Fertilize Tomatoes During the Season

Penn State Extension

Fertilize tomatoes at transplanting with balanced 10-10-10, then every 2-3 weeks throughout the growing season. Switch to low-nitrogen formula (5-10-10) when the first flowers appear. Stop fertilizing 2-3 weeks before your expected last harvest. Container tomatoes need feeding every 7-10 days with diluted liquid fertilizer. Early morning is the best time to apply.

What You Need to Know

Fertilize tomatoes at transplanting with balanced 10-10-10, then every 2-3 weeks throughout the growing season. Switch to low-nitrogen formula (5-10-10) when the first flowers appear. Stop fertilizing 2-3 weeks before your expected last harvest

Container tomatoes need feeding every 7-10 days with diluted liquid fertilizer. Early morning is the best time to apply.

For personalized recommendations based on your specific garden size and fertilizer, use our fertilizer calculator.

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