Answer: Mulching will help regulate soil temperatures, slow evaporation and suppress weeds, so I'd recommend putting some down around your tomato plants. I prefer to use organic mulch material (compost, aged-manure, straw, etc.) so that I can dig it into the soil after the growing season to help improve the soil structure. If you don't have access to organic mulch such as the above, pine chips will work just as well. The only difference is that pine chips will take several years to decompose so you won't be able to dig it into the soil after this growing season.
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