Bulb Spacing Calculator

The Bulb Spacing Calculator tells you exactly how many flower bulbs you need to fill a garden bed based on the bulb type and your chosen layout. Enter your bed's length and width, select a bulb type (tulips, daffodils, crocus, and more), and choose a planting pattern to get the total bulbs needed. Secondary outputs include spacing used, bulbs per square foot, and recommended planting depth — or enter a custom spacing to override the defaults.

ft
ft
inches

Override recommended spacing for your bulb type

Results

Total Bulbs Needed

--

Total Area

--

Spacing Used

--

Bulbs per Square Foot

--

Recommended Planting Depth

--

More Biology Tools

Frequently Asked Questions

What bulbs should I plant in fall?

Fall is the ideal time to plant spring-blooming bulbs like tulips, daffodils, hyacinths, and crocuses. These bulbs need a cold winter period to bloom properly in spring.

What bulbs can I plant in spring?

Spring is perfect for planting summer-blooming bulbs such as gladiolus, dahlias, begonias, and lilies. These tender bulbs cannot survive freezing temperatures.

How deep should I plant bulbs?

The general rule is to plant bulbs at a depth that's 2-3 times their height. Larger bulbs like tulips go 6-8 inches deep, while smaller bulbs like crocuses need only 3-4 inches.

What are some easy bulbs to grow for beginners?

Daffodils, crocuses, and alliums are excellent choices for beginners. They're hardy, deer-resistant, and naturalize well, coming back year after year with minimal care.

When should I plant daffodil bulbs?

Plant daffodil bulbs in fall, ideally 6-8 weeks before the ground freezes. In most areas, this means September through November, depending on your climate zone.

Can I plant bulbs in containers?

Yes! Most bulbs grow well in containers. Use well-draining potting mix and ensure the container has drainage holes. Container bulbs may need winter protection in cold climates.

How do I calculate spacing for irregular garden shapes?

For irregular shapes, break the area into smaller rectangular sections and calculate each separately, then add the totals together. This calculator works best for rectangular areas.

Should I fertilize bulbs when planting?

Add bulb fertilizer or bone meal when planting, and apply a balanced fertilizer in early spring when shoots emerge. Avoid high-nitrogen fertilizers which can promote leaf growth at the expense of flowers.