Hanging Basket Calculator — Plants & Compost
Work out compost, liner, and plant quantities for hanging baskets.
How We Calculate This
Basket volume is approximated as a half-sphere: V = (2/3) × π × r³, reduced by 20% for plant rootballs.
Plant counts are based on standard basket planting guides: 3/5/7 top plants for small/medium/large baskets.
Wire baskets allow side planting for a fuller display, adding approximately 1.5× the top plant count in the sides.
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.