Q.Can We Use Potting Soil From Last Year Or Do We Need New Potting Soil Every Year?
I typically grow tomatoes in a large pot and want to know if I can use the same soil I used last year to grow tomatoes this year. Can you recommend amendments to the soil that would make this possible? Also I typically grow petunias, geraniums, and veronica in large pots. Do these pots also need fresh potting soil every year, or can I just add 4″ to the top layer of soil?
Certified GKH Gardening Expert
Instead of adding soils, I would add compost or liquid fertilizers. I would, first, test the soils. Here are some articles to help: