Building a Microbog in a Chicago Kitchen Sink: Drainage, Hardy Species, and Winter Mulching

A Chicago (zone 5a) grower planned a microbog using an old double-bowl enamel sink (9×14″, 8″ deep) buried flush. They asked about drainage, plant capacity, hardy species, and fall vs. spring planting.

Jeff Dallas advised: don’t plug drains—stuff with long-fiber sphagnum to retain soil but allow drainage. Stagnant water causes anaerobic conditions. The sink can hold most hardy Sarracenia, Drosera, Pinguicula, and flytraps. For small bowls, choose slower growers: S. purpurea ssp. purpurea, ‘Judith Hindle’. Top-dress with live sphagnum. Avoid tender species (D. tracyi, Florida forms, P. primuliflora). Mulch heavily for winter—wait for several frosty nights with daytime highs in the 40s°F (now through month-end in zone 5a).

Follow-up: Mulch timing confirmed—apply after consistent overnight frost, before snow/arctic blasts. Pre-mulch steps (cleanup, fungicide) are critical.