About HarvestMath

Who’s behind the site

HarvestMath started the way a lot of useful things do: with a small, annoying problem that kept happening. Standing in a garden center aisle, trying to turn “3 inches of mulch over a 12 by 8 bed” into a number of bags before the truck rental ran out. The phone calculator technically worked, but it didn’t know what a bag of mulch was, and by the third project it felt ridiculous to keep doing that math by hand.

So the tool we wished already existed got built instead: type your bed, pick your depth, get an answer in the units the store actually sells — no sign-up, no email gate, no popup between you and the number. It fixed one small, recurring annoyance for us. It turned out a lot of other people had the exact same one, which is the only reason this is a website and not just a note on someone’s phone.

An honest note: HarvestMath is run by a small team, not a single named gardener with a bio photo, and we’d rather say that plainly than invent a founder story to sound more relatable. If that ever changes, we’ll update this page to match — a real name and a real story are worth more than a manufactured one.

What the site is for

At its core, HarvestMath is a growing set of free calculators for anyone with dirt under their fingernails — gardeners, homeowners, landscapers, indoor growers, the occasional accidental plant parent. Every tool here is built around the same few promises:

• Free to use. No sign-up, no email wall, no “create an account to see your result.” Type your numbers, get your answer, get back to the garden.
• Fast. Pages load quickly and the answer updates as you type — no submit button, no page reload.
• Mobile-first. Most visitors find us on a phone, often standing in a store aisle. Big tap targets, no zooming, no popups covering the answer.
• Built to be genuinely useful rather than ad-stuffed. The calculator is above the fold; the explanation is below it for anyone who wants the math. Ads and affiliate links exist, but they don’t bury the tool.

How the calculators are built

The formulas and recommendations behind these calculators — soil ratios, mulch depth, plant spacing, fertilizer rates — aren’t proprietary research or a guess dressed up as one. They reflect commonly cited guidance from university cooperative extension services and standard horticultural reference material, translated into tools that quietly do the arithmetic so you don’t have to. Every calculator page links to its sources, and we go back and review them as that guidance shifts.

For the full picture of where the numbers come from and how we review them, see our methodology page.

How the site stays free

An honest note on monetization: HarvestMath is supported by ads and affiliate links. When you click an affiliate link — to a tool, a bag of soil, a grow light — and make a purchase, the site may earn a small commission at no extra cost to you. That’s what keeps every calculator free, fast, and open to anyone who lands on it. We don’t recommend products because they pay more — we recommend what we’d actually put in our own cart.

The full breakdown of how affiliate links work, where they appear, and how we pick products is on our affiliate disclosure page.

Say hi

If you’ve got a question, a correction, a calculator you wish existed, or you just want to tell us your bed turned out great, reach out. A real person reads every message — and honestly, some of our favorite calculators on this site exist because someone wrote in and asked for them.