Dear Guy,

Thank you for contacting Ask Extension about soil testing. 

This is a good time to get a soil test to establish the base levels of soil nutrients. Soil testing is the only way to know which nutrients are needed and how much. 

We don't recommend specific labs, but I've included links for Oregon labs and another which has been reported to be especially good for home gardeners:

• www.simplysoiltesting.com
• https://catalog.extension.oregonstate.edu/ec628
• https://catalog.extension.oregonstate.edu/em8677
• https://catalog.extension.oregonstate.edu/ec1478

Soil tests generally do not give you the nitrogen (N) content of your soil because it is mobile, (ie. it moves rapidly through plants and soil.) Vegetables use a lot of N, and it can wash out of the soil through rain and irrigation. Sources of N include alfalfa meal, cottonseed meal, blood meal, or ammonium nitrate. (Use these exactly as directed on the labels.)

With regard to composts, we do not maintain a list of sellers but I recommend that you buy from a reputable nursery or landscape supply. They should know the source of the composts materials and can provide the percentage of organic matter. Some "composts" are actually mixes of topsoil, sand, or other materials that you may not need or want.

I hope this information is helpful. Please write again if you have other questions.