Did you have a cold snap, followed by warmer weather? I had a very late "tail end" 'Persian Berry' bloom do that to me last year. All the others were nice and tall, with prolific blooms, but the last straggler bloom appeared just like that, from the foliage base. We had a very rapid shift to our summer heat right before it showed up. Wonky weather can sometimes cause short-stemmed TB's. I've had it happen in my garden occasionally. As others have said, weather can affect the stalk height. Also, how's the watering? Have you been short on rain or a little lax on watering? Life happens, and weather happens... but sometimes if the water is in short supply, they can have short stalks like that. Also, new transplants can sometimes throw short stalks like that. I think the common denominator is some sort of environmental stress. It's probably not permanent, and subsequent stalks and/or seasons should be better for you, Good show of the Persian Berry, with spiderwort and 'Pierre Menard' antiques.
