Compost Bin and Soil Question

by Brian
(CA)

I began a compost bin a few weeks ago and placed Scott's lawn soil in it as my soil source. I have been reading a variety of reviews and I believe I may have messed up by using the lawn soil instead of the correct one. I have done 2 layers so far of the lawn soil, each about 2-3 inches thick. I have also added carbon and nitrogen-rich materials as well as manure.

In your opinion, will I need to dispose of this compost bin and start over? Or am I able to continue with the same bin but begin to add on the correct soil? Also, which soil do you recommend is the best to apply to a compost bin?


Thank you,

Brian

Some Answers…

Hi Brian and thank you for your question.

When you first start composting there are so many questions and everyone wants to do it right from the beginning.

You’ve added soil to your compost and are wondering whether the material is a problem and if so what soil I'd recommend. You don’t need to add any soil to the compost actually. It’s okay to add some but not necessary. And if you want to add some soil just using a thin layer from your own yard or from a neighbor’s fabulous garden might be worthwhile.

Let’s look at Scott’s lawn soil. I’m not 100% sure what is in Scott’s lawn soil. The details online say the nutrient analysis is .08 - .03 - .02. That refers to the nitrogen, phosphorus and potassium levels in the material. As a rule you want to avoid adding synthetic fertilizers to a compost bin as they can have a detrimental affect on the biology but even if this comes from synthetics at these concentrations I wouldn’t worry.

I’d like to know what the base is of this lawn soil. Is it a peat base or a compost base or something else?

If peat make sure it is very moist. Add lots of water to ensure it starts out wet. Dry peat is hard to get wet but once wet holds lots of moisture.

If it’s a compost base you might want to do a quick bioassay to make sure the very persistent herbicides aren’t in the compost. This product is for lawns and grasses are not affected by these herbicides but many veggies are.

This also goes for the manure. Horse manure in particular may be a problem as horses are super fussy about their food and so often horse pastures are treated with these persistent herbicides. This ensures the food for the horse is 100% grass. One big compost facility in California found that 80% of the horse manure arriving at their facility for composting was contaminated with these herbicides.

Go to the herbicide page for directions on doing a bioassay.

I do believe your compost is going to be just fine but it is worth doing a bioassay. If it shows the herbicides then you can use the compost on your lawn but don't use it in your veggie garden.

If you have more questions feel free to contact me or ask in the comment section.

Best of luck,
Leslie