About Blackgold Bin

Blackgold Bin is a working compost log. Every entry is a record of one batch or one method run at a single garden bench: the feedstock weights as they went in, the C:N ratio that was calculated before the pile was built, the moisture reading at each turn, and the temperature curve as it actually ran — including the days when a pile stalled, soured or overheated. The numbers are from a kitchen scale, a 50 cm compost thermometer and a pH meter, not from a textbook.

Composting advice is usually given as rules of thumb that were true for someone else's climate, materials and scale. Two parts brown to one part green by volume works until your brown is sawdust at 450:1, and 'turn every two days' works until your pile is 0.3 m³ and cannot hold heat between turns. The log exists to show the arithmetic behind the rules, so a reader can work out what applies to their own material rather than following a rule off a cliff.

Weight: a bathroom scale, with the bucket weight subtracted. Temperature: a 50 cm stem thermometer inserted 30 cm into the core, read before and after each turn. Moisture: the squeeze test, cross-checked monthly by drying a 200 g sample. C:N: calculated from published per-material values rather than lab analysis, so treat the ratios as working estimates with an error of roughly 10 %. Where a lab analysis is quoted it came from a commercial soil lab and the method is stated.

It is not a commercial compost supplier, and nothing here is for sale. It is not affiliated with any tool, bin or inoculant brand: where a product is named it is because it was used, not because of any arrangement. It is not a substitute for local advice on regulations — rules on composting food waste, burying bokashi and using manure differ by municipality, and in some places are restricted.

Numbers in this log get corrected when a mistake is found. Where a batch is re-measured or a figure turns out to have been recorded wrongly, the entry is updated rather than quietly rewritten, and the change is noted at the foot of the page. Readers who spot an error can write to the address on the contact page.