Porosity of compost

Asked March 5, 2017, 11:25 AM EST

I have raised beds for my vegetable garden. I purchased a locally compost mix last year to fill the beds. I also layered with dried hay alternately. My problem is with the compost. When watering, the water sits on top and doesn't penetrate the compost layer. You can observe small fine woody particles floating on top. Eventually, it will drain, but not feel moitened. What can I do to increase the soils ability to become porous and yet hold some moisture? Thank you.

Hood River County Oregon

1 Response

Sorry for the delay in sending a response. Perhaps the Expert previously assigned your inquiry is out of town.

Whenever water sits on top of potting mix, soil or compost, it means that the material is so dry that it will shed water rather than absorb it. The way to overcome that is to moisten the material with hot, to boiling, water. Accomplishing that will obviously be easiest to do with a relatively small amount of compost. In a garden bed, you could moisten a moderate amount of soil/compost mixture with hot water and, then, mix that into more of the dry soil/compost mixture. You would need to continue that incremental process until the bed is moderately moist throughout.

Another potential problem in your bed last season was the layering of soil and straw. Water moistens soil best when the soil is a uniform mixture.

The bed and its contents should be in good condition by now if it has been exposed to the more than abundant rainfall we’ve had this fall and winter. If not, uncover the soil and allow the rainfall start the moistening process for you.

Resources for you:

- Raised Bed Gardening - https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/fs270_1.pdf

- Growing Your Own – This has a general overview of gardening; page 7 has a planting chart for vegetables; you’re are in Region 2. https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9027.pdf

Enjoy your garden!