The plant in the first photo looks like sweet annie (Artemisia annua). The second plant looks like goldenrod (Solidago sp.). The third one looks like a potato.

ckc

Thanks so much! 

Can the first be used medicinally, from the garden?  If so how?  I noticed that these species are found in the nutritional supplement stores in the form of pills or tincture.  

And how do I know when to harvest the potatoes?

Thanks!

Best,

Amanda 

You're welcome.

You can harvest potatoes any time after they begin flowering if you want small "new" potatoes. If you want larger potatoes with a thicker skin (which will store better), you can wait until after the foliage dies back. You can find more information about potato harvesting on our website.
https://extension.umd.edu/hgic/learn/potatoes

We do not have medical advisors on staff and do not give advice about medicinal uses of plants. We recommend that you ask your doctor.

ckc