Duration of nutrient availability in compost

Asked February 26, 2018, 1:06 PM EST

I use compost made of yard waste in my potted plants. I'd like to know how long it's reasonable to think that the compost nutrients will remain available to the plants (present in the pot) after potting. Also, if nutrients are list, is it through uptake by the plant, lost to runoff, etc? This information will be useful in determining how often to add additional compost to the pots and/or repot.

Prince George's County Maryland

1 Response

It is impossible for us to give you an exact answer. The rate at which compost breaks down is influenced by temperature and moisture levels. Some nutrients will be absorbed by the plant and some will inevitably wash through. Also, each batch of compost of each source has different ingredients that are going to determine what nutrients are available. If you want to know precisely what nutrients are in your compost, you would have to do a soil test of each batch.

Fresh organic materials lose more than half their volume by the time they are fully decomposed. You will need to replenish the containers each year.