Dear Dr. Worm: the advice column written by someone with no spine whatsoever.

Dr. Worm has spent his entire life underground thinking about soil, and he has opinions. Ask him anything about worm castings, composting, soil, or your garden — the best questions get answered right here on this page and in the monthly newsletter.

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Questions We’re Asked All the Time

🔥 Will worm castings burn my plants?

Dr. Worm says: I eat garbage for a living and even I believe in restraint. Castings are gentle stuff with a low burn risk — nothing like synthetic fertilizer. That said, more isn’t automatically better. Follow the application guidelines and your plants will thank you by not dying.

📏 How much should I use?

Dr. Worm says: A little goes a long way — I should know, I produce it a pellet at a time. We have a whole guide with exact amounts for houseplants, seedlings, vegetable gardens, trees, flower beds, and containers. The short version: you’d have to work pretty hard to overdo it.

🪱 Can I use them on seedlings?

Dr. Worm says: Absolutely — seedlings are my favorite audience. They’re gentle enough for the tiniest sprouts and the microbes give young roots a head start. Mix a little into your seed-starting mix and watch them show off.

👃 Do worm castings smell?

Dr. Worm says: Only like a forest floor after rain, which is to say: wonderful, unless you’re weird. If your castings smell bad — sour, rotten, swampy — something went wrong upstream (usually a bin gone anaerobic). Good castings smell like good dirt. I would know. I live in it.

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