I grow in pots and troughs I wish to reuse the compost as I only use some for a few weeks. I grow peas and change the compost to plant the next batch. I rotate 5 troughs planting every 3 weeks and harvesting then replanting so I have a continuous supply off peas. I wish to save the compost to use with my other plants can I do this or is it a bad thing to do. I will not use compost for same plant groups.