This is a Mullein (Verbascum), and they can be common weeds in areas of poor, disturbed soil. While that may not necessarily describe your garden, one or more plants may have recently seeded-in to a nearby open space and served as the seed source for this volunteer. It's also possible wildlife deposited seed while passing through the yard.

About five species occur in Maryland, none of which are native. This appears to most closely match Common Mullein (Verbascum thapsus); here's a gallery: https://www.marylandbiodiversity.com/view/2799

Miri

Ideally the plant should be removed so it doesn't contribute to additional population spread, since some Mulleins are deemed invasive. That said, they are so widespread in the state that keeping or removing this individual won't make a huge difference. Still, it could reproduce and spread further in your yard or a neighbor's in future years. At the very least, we'd suggest cutting back the flowering stalk once they flowers are spent so they don't set seed.

Miri

You're welcome!