Plant spacing calculator
Planning a vegetable bed or a border? Enter bed size and the spacing on the plant tag — get the count and the grid layout.
Result
Plants needed
How many plants fit my bed?
Formula
plants = bed ft² ÷ (spacing in ft)²
rows = bed width ÷ spacing · per row = bed length ÷ spacing
Example: a 4 × 8 ft bed at 12 in spacing: 32 ÷ 1 = 32 plants — 4 rows of 8. At 18 in (peppers): 14 plants. At 24 in (bush tomatoes): 8.
Cheat sheet: common spacings
| Plant | On-center spacing | Plants in a 4×8 bed |
|---|---|---|
| Lettuce, spinach | 8–10 in | 34–46 |
| Bush beans, beets | 6 in | 64 |
| Peppers, broccoli | 18 in | 14 |
| Tomatoes (determinate) | 24 in | 8 |
| Zucchini, potatoes | 36 in | 3–4 |
Spacing on seed packets assumes field rows with walkways; raised-bed gardeners can usually tighten by 20–30% because soil is better and reachable from both sides. Crowding past that costs yield, not saves it.
Next step after the count: fill the bed — raised bed soil calculator.
Frequently asked questions
How many plants can I fit in a 4×8 raised bed?
32 at 12 in spacing, 14 at 18 in, 8 at 24 in. The calculator's grid rows × per row shows the actual layout.
What does 'spacing on center' mean?
Distance from one plant's center to the next plant's center — the number on plant tags and seed packets.
Can I space plants closer in a raised bed?
About 20–30% tighter than field spacing (better soil, no walkways needed). The dropdown chips cover the tight end of tag ranges.
How many tomato plants in a 4×8 bed?
8 determinate at 24 in; 4–6 indeterminate if you cage and prune them up strings.
How do I calculate spacing for bulbs?
Same math: bulbs go 2–3× their own diameter apart — tulips ~4–5 in, daffodils ~6 in. A 4×8 bed takes ~180 tulips at 4 in.