For the last couple months, I honestly thought my Endless Summer Hydrangeas had miraculously spread their seeds. I understand that ES are typically sterile, but I was very hopeful nonetheless. As they grew, the seedlings' leaves looked so much like Mophead leaves. Even the growth patterns were similar. I searched high & low to find data, pictures, or similar personal accounts of Hydrangea seedlings, but found very little.

Sadly, now that the flowers are starting to form, I have realized that I was mistaken & they are not Hydrangeas. The seedlings must be weeds. I guess I will not be revolutionizing horticulture after all. Yet still, I have not been able to identify these seedlings through online searches. I am SO curious.

They grow only in my beds with Hydrangeas in them, generally right next to my Hydrangea plants. Their leaves are almost identical. The leaf vein patterns appear the same, but the serrations are bigger & farther apart. The leaf color & texture are similar. The exception is that they form flower stalks almost like a Basil plant does, upright and producing small white flowers. Their fibrous root systems expand quickly. Does anyone know what they are? Please see pictures below. Thanks in advance!

Meredith