FullCalculator

Flower Bulb Planting Calculator

Bulbs for an Area

Calculate how many bulbs to fill a planting area

Succession Bloom Planner

Plan for continuous blooms from early spring to fall

Formula

Bulbs = Area (sq in) / (Spacing × Spacing) × Density Factor | Standard: Tulips 5", Daffodils 6", Crocus 3" spacing

Frequently Asked Questions

How many flower bulbs do I need per square foot?
It depends on the bulb type: Crocus/Muscari: 12-16 per sq ft, Tulips: 5-8 per sq ft, Daffodils: 4-6 per sq ft, Hyacinth: 4 per sq ft, Allium: 2-3 per sq ft, Lilies: 1 per sq ft, Dahlias: 1 per 2-3 sq ft.
When should I plant flower bulbs?
Spring-blooming bulbs (tulips, daffodils, crocus): Plant in fall, 6-8 weeks before the ground freezes. Summer-blooming bulbs (gladiolus, dahlia, lily): Plant in spring after last frost. Bulbs need cold temperatures to trigger blooming.
How deep do I plant flower bulbs?
General rule: Plant bulbs 2-3 times their height deep. Small bulbs (crocus): 3-4 inches. Medium bulbs (tulips, daffodils): 6-8 inches. Large bulbs (allium, lily): 6-8 inches. In cold climates, plant slightly deeper for insulation.

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