Sunflowers in full bloom but only 2.5 ft tall.
I started some Russian Mammoth Sunflowers indoors at the end of January and they got quite stunted for various reasons. When I transplanted them in March they recovered quite well, or so I thought. Right now they're only 2.5 feet tall but have a completely opened flower about 5 inches in diameter. They don't have much foliage at all but the little they do have is a healthy green. They don't really look unhealthy, just more like a small sunflower. I've never grown sunflowers before so I have no idea what their progress should be. I'm assuming there is something wrong with these.
At the same time that I transplanted them in the middle of March, I also sowed some seeds and those are about 1 foot tall with big lush green leaves.
Basically, I'd like to know the general progress of a Mammoth sunflower and also what would have caused my transplants to bloom so small (other than being stunted indoors). How tall should they be after 30 days? 60 days? etc.