Bulb Spacing: How Many Bulbs Should I Plant Together?
Looking for tips on figuring out how many flower bulbs you need for a flower bed?
In this guide, we'll cover bulb spacing and the "bulb math" used for calculating how many bulbs your bed needs, with recommendations for higher- and lower-density planting.
What Is the Right Spacing for Planting Flower Bulbs in A Garden?
Wondering “how far apart should I plant my flower bulbs?” This chart shows basic bulb spacing and how many to plant per square foot.
| Bulb Type | Spacing* | Bulbs per Sq Ft |
|---|---|---|
| Extra Large Bulbs: Large Alliums | 12+" | 1 |
| Large Bulbs: Alliums and Large Daffodils | 9–12" | 1–2 |
| Medium Bulbs: Tulips, Hyacinths, Most Daffodils | 4–6" | 4–6 |
| Small Bulbs: Grape Hyacinth, Crocus, Wild & Species Tulips, Squill | 3–4" | 9–12 |
Shop All Fall-Planted Flower Bulbs
*Spacing needs can vary by bulb variety. Please refer to your bulb’s product page or packaging to confirm its recommended spacing.
Bulb Math: How to calculate the number of bulbs needed?
Measure your space to determine how many square feet you’re planting:
a. For rectangles: length x width = areab. For circles: radius x radius x 3.14 = area
Then, multiply your total square feet by the recommended number of bulbs per square foot.
For example, you want to fill your garden with tulips, and the garden is 3' wide and 10' long:
- 3' x 10' = 30 sq ft- 30 sq ft x 6 bulbs per square foot = 180 tulip bulbs
Can You Plant Bulbs Really Close Together for A Dense Look?
Absolutely. If you’re inspired by the look of a botanic garden in full bloom, such as Keukenhof in Holland, and you want to a really bold display of blooms for maximum impact in the spring garden, you can plant bulbs on the higher side of the bulbs per square foot listed in the chart above.
For example:
How many tulip bulbs should you plant per square foot for a full look?
Plant six bulbs per square foot to achieve this appearance.
Planting bulbs densely is a good fit for:
- High-impact plantings along walkways and in garden beds and borders
- Cutting gardens
- Flowerpots and container gardens
What are the top bulbs for high-density planting?
- Tulips, hyacinths, crocus, anemones and Dutch irises are some of the best fall-planted bulbs for high-density planting. Daffodils and grape hyacinths (muscari) are also beautiful in that mix but plan on them multiplying over time.
High Density Planting Chart
If you want the maximum number of blooms in your flower bed, the chart below is an estimate of the number of bulbs you should buy.
| Bulb Type | 10 sq ft | 25 sq ft | 50 sq ft | 100 sq ft |
|---|---|---|---|---|
| Grape Hyacinth, Crocus, Squill | 200 | 500 | 1000 | 2000 |
| Large Daffodils | 75 | 205 | 420 | 1100 |
| Small Daffodils | 140 | 340 | 675 | 1350 |
| Large Tulips | 65 | 180 | 360 | 725 |
| Species Tulips | 75 | 205 | 420 | 1100 |
Wider Planting—For Naturalistic Planting or Established Gardens
There may be several reasons why you’d want to plant on the lower side of the bulbs-per-square-foot calculations shown in the chart above.
- If you are planting in a large drift where you would like a natural look, you can plant less densely.
- If you are adding to an established perennial garden, you will need to leave some room for your perennials to fill out.
Planting spring-blooming bulbs is a great way to extend the bloom time of your perennial garden. If you’re adding flower bulbs to your established garden, you’ll want to be mindful of the mature size of your perennial plants when adding bulbs. You can plant earlier-blooming bulbs around your perennials for a burst of blooms, while perennials (such as peonies, daylilies, hostas, coneflowers, phlox and irises) are just waking up for the season. After daffodils, tulips and other spring-blooming bulbs fade, the perennials will grow up around them to cover their dying foliage. With their tall stems and pops of color, alliums are also great bulbs to plant among perennials.
Bulb Math: Adding bulbs to a garden
To find your planting area, subtract the space perennials take up from your garden's total square footage—allow 1–2 sq ft per perennial, using the higher end for larger plants.
For example, your 300 sq ft garden has 10 large perennials in it:
- Multiply 2 sq ft x 10 plants = 20 sq ft
- Subtract 300 sq ft – 20 sq ft. That leaves 280 sq ft of planting area.
See our guides to learn more about how to plan and plant naturalizing bulbs:
- Best Bulbs for Naturalizing
- Naturalizing with Daffodils
Guide for Planting Different Types of Bulbs in One Garden
If you are planning a flower bed or a garden that features a mix of bulbs, how should you calculate how many bulbs you need?
Bulb Math: Planting a mix of bulbs
Decide what percentage of your garden space you'd like each flower type to fill, then multiply that percentage by your garden's total square footage to find the square footage for each variety. Next, multiply each variety's square footage by its recommended bulbs-per-square-foot rate to find how many bulbs of that variety to buy.
For example, you would like your 300 sq ft garden to feature 60% daffodils and 40% crocus:
1. Multiply 60% (.6) x 300 sq ft = 180 sq ft for daffodils
2. Multiply 40% (.4) x 300 sq ft = 120 sq ft for crocus
180 sq ft x 4 daffodils per square foot = 720 daffodil bulbs
120 sq ft x 9 crocus per square foot = 1,080 crocus bulbs
Spacing and Planting Tips
- Planting one straight row of evenly spaced bulbs often looks sparse—planting in quantity in non-linear patterns will always give a richer appearance. This is why mass planting has always been the traditional way to use bulbs. Mass plantings can include dozens or even hundreds of bulbs—especially for a large-scale naturalizing project. If you don't have room for mass planting or need to start small, a reliable way is to plant in clumps of at least six or more bulbs. This is an attractive method for hyacinths, daffodils and tulips. See their spacing recommendations above.
- Another bulb-planting method uses layering instead of side-by-side planting and is called “lasagna planting.” This is often used in containers and small spaces, where you want to fit as many bulbs as possible. Learn more about it in our guide: Lasagna Planting with Bulbs
FAQs About Bulb Spacing
What happens if you plant too many flower bulbs together?
If your bulbs are too crowded, you may see reduced flowering or smaller plants. You can dig up and re-plant bulbs in the fall to space them out more.
What happens if you plant too many daffodil bulbs together?
Daffodils are known to naturalize, or multiply as they grow over time, so they may become crowded after a few seasons. If you see small plants or reduced flowering, you can dig up bulbs in the fall and re-plant them with more space.
Compare flower bulb spacing for a container garden vs. a flower bed.
Generally, gardeners prefer to plant bulbs more densely in a container garden than in a flower bed for maximum impact. Learn more about layering bulbs, a technique often used for containers, in our guide: Lasagna Planting with Bulbs
Compare the planting densities of tulips and daffodils in a garden.
Though the bulbs of daffodils and tulips are generally similar in size, you may want to consider planting daffodils less densely. Daffodils multiply over time, so they may become crowded. While some tulips are hardy and come back for years, others fade sooner and require more frequent replanting. For maximum impact, plant tulips very densely for a vibrant spring show.
More Gardening Resources
- See Breck’s How-to Gardening Guides for guides on how to plant tulips, daffodils and other flower bulbs
- Visit Breck’s Blog for more planting ideas
- Shop Breck’s fall-planted bulbs