Reporting
Yes, lack of blooms is

Yes, lack of blooms is generally due to excess nitrogen. You could sprinkle some superphoshate around the plants. It may not work this year, but you can try it. What will be important is that you get a soil test before you plant next year. There are home gardening soil tests you can get from your local cooperative extension or from local places for a small fee.  Then adjut the soil as needed.