Plant Spacing Calculator
Offset rows fit 13% more — in a bed big enough to notice.
Work out Plant Spacing. Offset rows fit 13% more — in a bed big enough to notice. Shows the working, not just the answer.
Plants needed
108
8 rows of up to 14 · Triangular (offset rows) — denser packing at the same spacing
Offset rows pack denser than a square grid at the same centre-to-centre spacing — about 13% more plants across a large area, because hexagonal packing beats square packing. That is why nursery planting plans for ground cover are always staggered. In a small bed the advantage can reverse, since every offset row loses a plant at one end and the edge penalty outweighs the density gain. The comparison row shows the actual difference for your bed rather than repeating the general rule. Spacing should be based on the mature spread, not the pot size. Planting on final spacing looks sparse for two seasons and correct thereafter; planting on how it looks today means lifting half of them later.
How the Plant Spacing Calculator works
How many plants fit a bed at a given spacing, in a square grid or offset rows. Offset spacing packs about 13% denser across a large area, and this shows the actual difference for your bed rather than repeating the general rule.
Also known as: how many plants per square metre · ground cover plants needed · staggered planting layout · how many plants for my bed
Frequently asked questions
How many plants do I need per square metre?
One divided by the spacing squared, roughly. At 30 cm spacing that is about 11 per square metre in a square grid; at 45 cm it drops to 5. Offset rows fit somewhat more across a large area.
What is triangular plant spacing?
Offsetting alternate rows so each plant sits between two in the row behind. It is hexagonal packing, which is denser than square packing, and it gives about 13% more plants at the same centre-to-centre distance.
Why does the calculator say offset rows fit fewer plants in my small bed?
Edge effects. Every offset row loses a plant at one end, and in a small bed that penalty outweighs the density gain. The result shown is the truth for your bed rather than the general rule applied blindly.
Should I space by pot size or mature size?
Mature spread, always. Planting at final spacing looks sparse for two seasons and correct thereafter; planting to how it looks today means lifting half of them once they meet.
Does closer spacing suppress weeds?
Yes, and it is the main reason ground cover is planted densely. Once the canopy closes there is no light reaching the soil, and annual weeds stop germinating — usually a season sooner at tight spacing than at wide.
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