Top-Dressing Soil with Manuare
Question
February 12, 2015
When I dress the top of the garden with hot manure, should I water it in and turn it under as well? I was told that adding hot manure would "heat up" the soil, chemically speaking, and kill off some viruses that have been plaguing my tomatoes sooner and sooner in the season. Thanks.
Answer(s)
Answer by JH: This is a very good and timely question so thank you for asking. Everyone has their preferred ways of doing things but caution is advised due to the fact that manure has a high salt content and tomatoes are sensitive to salt as are many vegetable plants. Also if the soil isn't watered sufficiently for the entire time the manure is "hot", you might burn your plants. Additionally, if the animal supplying the manure was dewormed, the manure might kill the worms in your soil.
You do have time to compost the manure prior to use by mixing it with shredded paper or cardboard or fall leaves or other carbon sources. Nmcomposters.org has more information about the proper mix for specific materials used to compost.
And in the future if you want to use manure, apply it to the soil in the late fall when plants are dormant, then water it well to leach out the salts. Also be aware that some manures may contain weed seeds.
Additional information on this subject can be found in the Bernalillo County Master Gardeners publication Down to Earth, pp 11-18. It is available at local nurseries.