Is it too late to fertilize? I had a soil test in the spring, purchased the supplements and never had time to apply.
Answer
At this point, just wait until spring and continue through the blooming season. Your fertilizer should be low in nitrogen, higher in phosphorus and low in potassium (5-10-5 ratio). Once a month applications are good for most annuals but twice a month for hybrid petunias, million bells and new sunflowers bred for cutting. Perennials do well with the once a month treatment.