About this calculator
Free Garden Plant Spacing Calculator - calculate garden plant spacing for everyday decisions. Practical calculator for daily use.
How to use
Enter your values in the fields above and click Calculate to see your results. Click Clear to reset all fields.
What the garden spacing calculator does and when to use it
Plants set too close compete for light, water and nutrients and stay damp enough to invite disease, while plants set too far apart waste bed space. This calculator estimates how many plants of a chosen type fit in a rectangular bed, using a standard in-row spacing for each crop and laying the plants out on a square grid. You enter the bed length and width in feet and pick the plant, and it returns the total number of plants, the number of rows, the number of plants per row and the spacing used.
Use it when planning a raised bed, deciding how many seedlings to start or buy, or comparing how many plants of different crops a bed can hold. The spacing values are typical planning figures. Seed packets, extension guides and variety descriptions may recommend different distances, especially for compact or vining varieties, so treat the result as a first estimate.
The method and its variables
- L and W are the bed length and width, converted to inches by multiplying by 12.
- Spacing (s) in inches: tomato 24, pepper 18, lettuce 8, carrot 3, bean 6, squash 36.
- Rows = floor(W / s), the whole number of plants that fit across the width.
- Per row = floor(L / s), the whole number that fit along the length.
- Total plants = rows × per row.
Because each count is rounded down, partial spaces at the bed edge are not counted, which keeps plants from being placed too close. The same distance is used between plants and between rows.
Worked example
A raised bed is 8 feet long and 4 feet wide, planted with tomatoes. The bed is 96 by 48 inches. With 24-inch spacing, rows = floor(48 / 24) = 2 and per row = floor(96 / 24) = 4, so the total is 2 × 4 = 8 plants. The calculator reads Total Plants: 8 | Rows: 2 | Per Row: 4 | Spacing: 24" apart.
Switching the same bed to peppers at 18 inches gives floor(48 / 18) = 2 rows and floor(96 / 18) = 5 per row, so 10 plants. With carrots at 3 inches the grid is 16 rows by 32 per row, or 512 plants. That last number shows the limit of a square grid: carrots are usually sown thickly in rows and thinned rather than placed one by one.
Common mistakes and how to interpret the result
- Applying it to every variety. Determinate bush tomatoes, indeterminate staked tomatoes and sprawling squash differ in space needs. Follow the tag on your variety when it differs from the default.
- Forgetting the walking space. The bed dimensions should be the planted area. Add paths or reachable access separately, since beds wider than about 4 feet are hard to tend from the edges.
- Planting right at the border. Plants near the edge of a raised bed often need a little clearance from the wall, so leave a margin if your result relies on a nearly exact fit.
- Reading the total as a yield. The count is plants, not harvest. For harvest estimates use a yield calculator.
Related tools: Vegetable Garden Yield Calculator, Bulb Spacing Calculator, Raised Bed Soil Cost Calculator and Seed Packet Yield Calculator.