Corrections and errors
Tell us the page, the number you think is wrong, and if possible where the right figure comes from. Corrections are usually live within a few days and the page's review date is updated.
Suggestions
A bag size or product we do not list, a calculator for a job we have not covered, or a guide you would like to see. Requests from New Zealand readers are especially welcome – we want NZ coverage to be as good as AU.
Privacy and advertising
Questions about data, cookies or the advertising shown on the site. See the privacy policy first – it covers most questions.
What we can and cannot help with
- We can: fix errors, add products and bag sizes, explain how a calculator arrives at a number, and take requests for new tools.
- We cannot: diagnose plant problems, recommend a specific supplier in your area, or give advice that replaces your local nursery or landscape yard. For growing advice, your state's gardening society, a community garden or ABC Gardening Australia are good places to start.
Response times
GardenMaths is a small project of DueRiva. Emails are normally answered within three business days; during spring – the busy season for gardens and for this site – it may take a little longer.
Business details
GardenMaths is an independent website, made by DueRiva, publishing free garden calculators and guides for readers in Australia and New Zealand. It has no retail operation and does not sell products. Publisher contact: hello@gardenmaths.com. Legal terms are at /terms-of-use/.