Bulb Spacing Calculator
Enter your planting area's length and width, plus your target bulb spacing, to estimate roughly how many bulbs you'll need.
Last updated: September 22, 2026
Frequently asked questions
Why are there two slightly different bulb count numbers shown?
The primary result (bulbs per row × rows) models an evenly spaced grid layout. The area-divided-by-spacing-squared figure is a simpler area-based approximation that can differ slightly, especially for areas that aren't a clean multiple of your spacing. Both are estimates - use the grid figure as the more layout-realistic of the two.
Does this account for staggered or offset bulb planting patterns?
No - this calculates a simple rectangular grid layout. Staggered (offset row) planting typically fits a modestly higher bulb count into the same area than a straight grid, since offset rows can nestle bulbs closer together within the same spacing rule - if you're staggering, expect to need somewhat more bulbs than this estimate.
Should I subtract space for a border or edge margin?
Yes, if your planting plan includes a margin around the bed's edge - reduce the length and width you enter here by that margin on each side first, since this calculator assumes bulbs are planted all the way to the edges of the area you enter.
What spacing should I use for different bulb types?
It varies by bulb type and size - larger bulbs like daffodils and tulips are commonly spaced around 4-6 inches apart, while smaller bulbs like crocuses are often spaced closer, around 2-3 inches. Check your specific bulb variety's planting guide for its recommended spacing.
Why might I need more bulbs than this calculator suggests?
Irregular bed shapes (not a clean rectangle), existing plants or obstacles within the bed, and a desire for denser visual coverage than strict even spacing can all mean buying more than the calculated estimate - many gardeners round up and buy a small surplus for exactly this reason.
Can I use this for a circular or irregularly shaped bed?
Not directly - this calculator assumes a rectangular area. For a circular or irregular bed, estimate its area separately (or approximate it with a rectangle close to its actual size) and use the area-based estimate as a rough guide rather than the row-by-row grid figure.