Bulb Planting Calculator
Enter your bed length and width, pick the bulb, and get the count to buy - bulbs per square foot from the spacing chart, packs of 25 rounded up, plus the planting depth and spacing for that bulb.
Planting charts answer per bulb; nobody plants one bulb. The real question at the garden centre till is how many bags a bed actually takes - and the honest answer comes from area arithmetic, not the optimistic picture on the bag.
How to use
- Measure the bed length and width in feet - drifts and borders, not single rows.
- Pick the bulb type; the chart carries depth and spacing for the five classics.
- Buy the pack count, plant pointy end up at the depth shown, and water once.
Frequently asked questions
How many tulip bulbs per square foot?
About nine at the standard 4 inch spacing - a 4 by 8 bed takes roughly 290, or 12 packs of 25. Crowd them to 3 inch spacing for a dense display and the same bed wants 12 per square foot, but drainage and bulb food suffer in year two.
How deep should I plant bulbs?
Two to three times the bulb height: tulips and daffodils 6 inches, crocus 3, giant alliums 6 with 8 inch spacing. Too shallow and frost heaves them; too deep and the shoot spends its budget getting to daylight.
Do tulips need chilling before planting?
In warm climates yes - 12 to 16 weeks in the refrigerator, away from ripening fruit, because a tulip without its winter never forms a proper stem and blooms at knee height on a flop. Daffodils and crocus shrug off the lack.
When should I plant fall bulbs?
October into November while soil is still workable - bulbs root best in cool soil and want roughly six weeks before the ground freezes. Planting into warm September soil invites rot; planting after freeze-up buries the season.