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I ran field research on how ozone and warming affect silver birch.
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Tools and Calculators

Free, science-based calculators for gardeners and herbal makers, built by a plant scientist
Built and checked by Serge, MSc, plant biologist and environmental scientist, grounded in hands-on research.
What are these tools? A set of calculators I built to answer the everyday number questions in gardening, soil care, and herbal preparation. Each one uses established science and cites government and university extension sources. They are for educational purposes and give practical guidance, not professional advice.

Soil & Compost

Compost mix of browns and greens

Compost Ratio Calculator

Balance carbon-rich browns and nitrogen-rich greens for a faster, cleaner compost pile.

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Healthy dark garden soil rich in organic matter

Garden Soil Carbon Estimator

Estimate the yearly carbon your soil can build from your bed size and the practices you use.

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Adjusting soil pH with lime or sulfur

Soil pH Adjuster

Find the lime to raise pH or sulfur to lower it, scaled to your soil type and area.

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Mulch and compost spread on a garden bed

Mulch & Compost Calculator

Turn bed size and depth into litres, bags and cubic metres, so you order the right amount.

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Seeds & Planting

Seeds being started indoors in trays

Seed Starting Calculator

Work back from your last frost date to find indoor sowing and transplant timing for each crop.

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Seeds sprouting in a germination test

Seed Germination Rate Calculator

Test old seed, get its germination rate, and see how many to sow for the plants you want.

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Seedlings spaced evenly in a garden bed

Plant Spacing Calculator

See how many plants fit a bed at a given spacing, in both a straight and a staggered layout.

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Herbs & Harvest

Fresh herbs ready to harvest

Herb Harvest Calendar

Plan the best harvest periods for culinary and medicinal herbs, by leaf, flower and root.

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Botanical name and plant family reference

Botanical Name Finder

Look up a common herb name to find its accepted botanical name, family and older synonyms.

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Teas, Oils & Salves

Herbal tea steeping in hot water

Herbal Tea Steeping Guide

Find steeping times, water temperatures and herb-to-water ratios for common infusions.

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Loose dried herbs for blending tea

Herbal Tea Blend Ratio Calculator

Split a total into base, supporting and accent herbs using the classic parts method.

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Fresh and dried herbs side by side

Dried-to-Fresh Herb Converter

Swap fresh and dried herb amounts both ways using the standard one-to-three ratio.

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Essential oil bottle with dropper and carrier oil

Essential Oil Dilution Calculator

Work out the drops of essential oil for a safe dilution, with clear strength and safety guidance.

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Homemade salve in a tin with beeswax

Salve & Balm Ratio Calculator

Find the beeswax to melt into your oils for a soft salve, standard salve or firm balm.

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These tools give general estimates and conversions for educational purposes and do not replace professional horticultural, agronomic, or medical advice. Always follow product labels and, for soil work, base decisions on a proper soil test.