How does plant spacing work?
Spacing is the distance from the centre of one plant to the centre of the next. Plant too close and they compete for light and water. Too far apart and weeds fill the gaps before the plants do.
Plants = area ÷ (spacing × spacing)
A bed of 100 ft² planted at 18 in (1.5 ft): 100 ÷ 2.25 = 45 plants in a square grid. Staggered, you need about 15% more, so 52.
Planning the rest of the job? Use the Bulb spacing calculator and the Plant population calculator too.
Square or staggered?
Square grid
Plants in straight rows and columns. Easy to lay out and weed between.
Best for vegetables and formal beds
Staggered
Each row is offset by half a space, like a honeycomb. Covers ground faster and looks natural.
Best for groundcover and mass planting
What are typical spacings?
The plant label is the best guide. Use the mature spread it gives as your spacing.