Excess Nitrogen in Tomato Soil: Balancing Nutrients Mid-Season

Huge Tomato Plants, Few Flowers? Classic Nitrogen Overload

Mushroom soil (spent mushroom substrate) is nitrogen-rich. Lush, dark green, flowerless tomatoes in Delaware confirm excess N with insufficient P/K for fruiting.

Mid-Season Correction (Limited Options)

• Stop all nitrogen inputs—no more manure, compost tea, fish emulsion
• Apply phosphorus/potassium: Bone meal (1 cup/plant) + kelp meal (1/2 cup/plant) scratched in
• Foliar feed: Bloom booster (0-10-10 or 2-10-10) weekly for 3 weeks
• Root prune: Cut 6-inch circle 12 inches from stem with spade—shocks plant into reproductive mode

What NOT to Do

• Don't add peat/compost now—decomposes slowly, releases more N
• Don't overwater to "leach N"—causes blossom-end rot
• Don't pinch flowers—they're already scarce

Long-Term Soil Balancing

Each fall and spring:

1. Add 1 inch leaf mold or composted leaves (low N, good structure)
2. Apply rock phosphate (5 lbs/100 sq ft) and greensand (10 lbs/100 sq ft)
3. Grow winter rye cover crop—scavenges residual N
4. Test soil annually; target 6.5 pH, balanced N-P-K

This Season's Outlook

Some varieties (determinates) may still set a late crop. Indeterminates often recover for fall production if heat breaks. Don't write off the season—tomatoes can surprise you.