Hi. I bought some Black Hen compost. The smell is pretty awful. I put it with some other compost on my garden that has spinach and other greens coming up. Why would the hen compost smell so bad? Does this indicate it is not thoroughly composted? Does it mean I can’t eat my greens raw because of dangers of E.coli or salmonella contamination?
Thanks for your help,
Because Black Hen is bagged compost, the composting company should have met certain composting regulations prior to bagging – including reaching a prescribed minimum temperature for a prescribed length of time. The heat will kill weed seeds and pathogens such as E. coli or salmonella. Assuming the composting company is in compliance with regulations (I consider Black Hen/Black Cow a reputable company), the compost you bought should have been thoroughly composted and would be fine to use on your garden right away. Our farmer expert, Tom Elmore, does not recommend using septic compost for seeds and starts, since they are more sensitive. Your greens should be safe to eat because what you applied was composted manure. It is not considered safe to eat raw greens from gardens that have recently added raw (uncomposted) manure. When raw manure has been applied to your garden, you should wait at least 120 days before harvesting raw greens. Raw manure is best applied in the fall prior to spring planting.
But why did it stink? It does seem like the chicken compost is generally stronger-smelling than the cow compost, but I suspect that the bags of Black Hen were on a pallet that got wet, which caused the conditions inside the bag to become waterlogged. The lack of oxygen in the bag (because of the waterlogging) caused the compost to go anaerobic. Anaerobic microorganisms produce by-products like ammonia or foul smelling hydrogen sulfide – sulfur can smell like rotten eggs. Anaerobic conditions could start to kill some of the good microbes contained in the compost, so applying the compost to your garden soil as soon as possible is a good idea. Once the compost is out of the bag, oxygen can re-enter the picture and hopefully reinvigorate any flagging beneficial microbes. The compost will definitely help lighten your soil and add fertility. I add some bagged compost to my garden every year, because I don’t produce enough homegrown compost to aggressively improve my soil.
For Home Composters:
Composting accelerates the decomposition of organic matter, whether that matter is your veggie scraps, dead leaves, grass clippings, or whatever. The ratio of Carbon materials (brown leaves, shredded paper) to Nitrogen materials (veggie scraps, grass clippings, manure) is important because the microbes in your compost utilize both carbon and nitrogen for different purposes. The carbon is used as a source of energy, and the nitrogen is used to build cell structure (grow) and reproduce. To keep the microbes happy and to keep your compost cooking, you want to provide as close to the ideal proportion of each component as possible. Opinions differ a little on the best Carbon:Nitrogen ratio, but somewhere between 25:1 and 40:1 is a safe bet. See the chart for some common ratios.
If your pile seems stalled out or stinky, it is time to use your powers of observation. When the C:N ratio is out of whack, composting will be slower/or crash because organisms die and must be regenerated to get things moving along again. If the pile is cold and dry, you need to add more nitrogen and possibly a little water. If the pile is hot, wet, and smells bad, it needs more carbon. Make your additions and turn the pile to get things homogenized and cooking again. When you turn the pile you are adding oxygen into the mix–oxygen is a must to keep the microbes happy (you die without access to oxygen, right?).
In a hurry? Shredding your organic matter to the 1/8”- 2” range will get things moving right away; shredded material has more exposed surface area that is attractive to microorganisms. Coarser material like small sticks and cornstalks will help keep the pile naturally aerated. Speed demons can turn their pile every 3 days to encourage decomposition, fluff up the pile, and keep it oxygenated. Turn daily if the pile has become swampy.
- Pile size should be big enough to generate heat – at least 3-4’ tall x 3-4’ wide.
- Temperature of 120 to 160 F [temps above 145 degrees kill weed seeds and fly larvae; temps above 131 degrees kill pathogens]
- Moisture content of 50 to 60% [too dry=slow microbial activity; too wet=no oxygen]
- pH of 6.5 to 8.5
- Bulk density of less than 40 lbs. per cubic foot
- The Science of Composting (great article)
- Composting On Organic Farms — article by Keith R. Baldwin and Jackie T. Greenfield
- Composting 101 for City Dwellers
When your compost is finished it will be stable, dark and crumbly, and smell sweet and earthy. Just one dimes thickness of well-made compost will be of great value to your garden.
Ruth Gonzalez is a former market farmer, gardener, local food advocate, and founder of the Tailgate Market Fan Club where she blogs at http://tailgatemarketfanclub.wordpress.com. In her job at Reems Creek Nursery, Ruth offers advice on all sorts of gardening questions, and benefits daily from the wisdom of local gardeners.
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Author: Ruth Gonzalez
Ruth Gonzalez is a former market farmer, gardener, and local food advocate who wants to see organic farms proliferate and organic gardens in every yard. She serves on the Organic Growers School Board of Directors, and in her job at Reems Creek Nursery, Ruth offers advice on all sorts of gardening questions, and benefits daily from the wisdom of local gardeners.