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Gardenly3D

Plant Spacing Calculator

Enter your garden bed dimensions and desired plant spacing to estimate the number of plants you need — with a visual layout preview in grid or triangular patterns. Results are approximate and intended for planning purposes only; always confirm final quantities against mature plant size and consult a professional for final specifications.

Calculate Plant Spacing

ft
ft
in

Total Plants Needed

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Bed Area

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Plants per Row

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Number of Rows

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Layout Preview

Enter dimensions to see preview

Each dot represents a plant position

How to Calculate Plant Spacing

  1. 1

    Measure your garden bed

    Find the length and width of the planting area. For best results, measure the plantable area inside any borders or edging.

  2. 2

    Determine plant spacing

    Check the plant tag or catalog for recommended spacing. This is the distance between the centers of adjacent plants. Common spacings range from 6 inches for ground covers to 36 inches for large shrubs.

  3. 3

    Choose your planting pattern

    Grid pattern places plants in straight rows and columns. Triangular (staggered) pattern offsets every other row, fitting more plants in the same area while creating a more natural look.

  4. 4

    Review your plant count

    The calculator shows the total number of plants needed, plus a visual preview of the layout. Add a few extra plants (5-10%) to account for losses during transplanting.

Pro Tips

  • Triangular (staggered) spacing fits more plants than grid spacing in the same area and creates a fuller, more natural-looking planting.
  • Always space plants based on their mature size, not their size at planting — overcrowded plants compete for water, nutrients, and sunlight.
  • Group plants in odd numbers (3, 5, 7) for the most natural and visually appealing arrangement in ornamental beds.
  • Annuals can be planted slightly closer together since they only last one season, while perennials need full mature spacing.
  • For ground covers, use triangular spacing at 75% of the recommended spacing for faster coverage — plants will fill in within one growing season.
  • Buy 5-10% more plants than calculated to replace any that don't survive transplanting.

Frequently Asked Questions

How many plants do I need per square foot?
It depends on spacing: at 6-inch spacing, you need about 4 plants per sq ft (grid) or 4.6 (triangular). At 12-inch spacing, about 1 plant per sq ft. At 18-inch spacing, about 0.44 plants per sq ft.
What is the difference between grid and triangular spacing?
Grid spacing places plants in straight rows and columns (like a checkerboard). Triangular spacing offsets every other row by half the spacing distance, fitting more plants into the same area and creating a more natural, fuller look.
How far apart should I space ground cover plants?
Most ground covers are spaced 6-12 inches apart. Fast spreaders like creeping thyme can be placed 12 inches apart, while slower growers like pachysandra do better at 6-8 inches.
How do I calculate triangular spacing?
For triangular spacing, plants per row = floor(bed width / spacing). Rows are spaced at spacing × 0.866 (the sine of 60 degrees). Every other row is offset by half the spacing distance. Our calculator handles this math automatically.
Should I plant in rows or clusters?
For formal gardens, grid rows create a structured look. For informal or cottage gardens, triangular spacing or naturalistic clusters of 3-7 plants look more organic. The calculator supports both patterns.
How many flats of plants do I need?
Standard flats hold 18 or 36 plants (varies by cell size). Divide your total plant count by the flat size to determine how many to buy. For example, 72 plants ÷ 18 per flat = 4 flats.

Results are approximate and intended for planning purposes only. Material densities, coverage rates, and quantities are estimates that may vary based on actual conditions, product specifications, and installation methods. Always consult a professional for final specifications.

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