Bulb Spacing Calculator

Calculate how many flower bulbs you need and the proper spacing for planting in garden beds, borders, and containers.

BULBS NEEDED
--
Bed Area
--
Bulbs per sq ft
--
Rows
--
Bulbs per Row
--

Flower Bulb Planting Basics

Proper bulb spacing ensures each plant has enough room to grow, access sunlight, and develop a strong root system. Overcrowding leads to smaller blooms and increased disease risk, while too much spacing creates a sparse, unfinished look.

The general rule of thumb is to plant bulbs at a depth 2-3 times their height and space them 2-3 bulb-widths apart. Larger bulbs like tulips and daffodils need more space, while small bulbs like crocuses can be planted closer together.

Spacing Formulas

Grid: Bulbs = (Length ÷ Spacing) × (Width ÷ Spacing)
Staggered: Bulbs = Grid Count × 1.15 (15% more bulbs)

Common Bulb Spacing Guide

Bulb TypeSpacing (inches)Depth (inches)Bloom Season
Tulip4 - 66 - 8Spring
Daffodil6 - 86 - 8Spring
Crocus3 - 43 - 4Early Spring
Hyacinth5 - 66Spring
Allium6 - 84 - 6Late Spring
Lily8 - 126 - 8Summer
Gladiolus6 - 84 - 6Summer

Frequently Asked Questions

What does staggered planting mean?

In staggered (triangular) planting, each alternate row is offset by half the spacing distance. This creates a more natural, dense look and fits about 15% more bulbs in the same area compared to a grid pattern.

How deep should I plant bulbs?

The general rule is to plant at a depth of 2-3 times the bulb's height. For example, a 2-inch tall tulip bulb should be planted 4-6 inches deep. In colder climates, plant slightly deeper for insulation.

Can I plant bulbs closer together for a fuller look?

Yes, you can reduce spacing by about 25% for a denser display. However, avoid touching bulbs together as this promotes rot and fungal disease. Ensure good drainage when planting densely.