Plan the season. Know the numbers.
Better planting starts with a plan.
Free planting calculators for growers who want to know when to sow, how much to plant, how much space they need, and when to expect a harvest or bloom.
- Plan with your dates
- Know your numbers
- Grow with confidence
Tools for every step of your planting plan
Plant Spacing Calculator
Enter your bed size and spacing to get plant counts, seeds needed, and tray requirements.
Seed Starting Calculator
Work back from your last frost to know when to start indoors, transplant, or direct sow.
Succession Planting Calculator
Plan repeat sowings at a set interval to keep the harvest coming through the season.
Bloom & Harvest Calculator
Estimate first bloom or harvest from a planting date and days to maturity.
Plan by crop
Each crop page combines spacing, timing and quantities into one plan, using planning defaults you can adjust to your own growing system.
Zinnia
Zinnia elegans
- Spacing
- 9″ (6–12″)
- Succession
- Supported
Dahlia
Dahlia spp.
- Spacing
- 12″ (12–18″)
- Succession
- Not typical
Sunflower
Helianthus annuus
- Spacing
- 6″ (6–18″)
- Succession
- Supported
Ranunculus
Ranunculus asiaticus
- Spacing
- 9″ (6–12″)
- Succession
- Not typical
Snapdragon
Antirrhinum majus
- Spacing
- 9″ (4–12″)
- Succession
- Supported
Tomato
Solanum lycopersicum
- Spacing
- 24″ (12–36″)
- Succession
- Supported
How Plantometry works
Step 1
Your dates
Start with the dates that define your growing season — your last spring frost and, when it matters, your first fall frost.
Step 2
Your space
Enter your bed dimensions, spacing and planting assumptions. Every planning default is editable.
Step 3
Your plan
Plantometry turns them into dates, quantities and practical next steps you can print and take to the field.
Planning, explained
Short, practical explanations of the math behind each tool. Every guide leads straight into the relevant calculator.