Sorry I can't answer most of your questions. Google may help with #1.

Are they annuals? Technically yes, but they reseed themselves easily. They *could* possibly last over a mild winter. I used to have some. The hardiest ones continued blooming into January in southern WI! (2006-2007 year). That was in Zone 5 with a very unusual winter. It probably died after temps sunk the second half of January into zub zero weather.

They reseed themselves quite readily, to the point of almost becoming an invasive weed. At least in Zone 5. Cooler temps seems to bring out more intense colors. They tend to look their best around Fall. In summer they seem to attract aphids.

Unfortunately I don't have any pictures readily available to upload to the internet. I don't have any Calendulas since I moved to MN. Just haven't planted any.

Yes they are annuals. Like fieldofflowers said they drop their seed quite readily and they are very cold tolerant. It takes a hard frost to kill them.

Calendula is a very old cultivar. It used to be grown as a herb. Some people still grow it that way. A healing salve for cuts, scrapes, and minor burns can be made from its flowers.

The tallest one is called Beauty or pacific Beauty. It is about 18 inches tall. The smallest one is Bon Bon and it is about 12 inches tall These come in mixed colors from cream to orange and yellow and every shade between those colors. There are also some newer hybrids that have been introduced--veseys has a new Apricot one, but I don't know how they behave in the garden because I've never grown them.

I tend to let them seed in one spot and then transplant the seedlings to bare spots in the garden later. I keep the rest deadheaded or get the seed off of them before it can fall so I'm digging out a lot of plants come spring because I think every dropped seed grows.

If you are planting them new, you can plant them outside when the daffodils break through the ground or just in very early spring.

I was very fond of Calendula from seed that I got from my late MIL. They were tough, reseeded readily and the like.

I have not found the same tough plant qualities among the doubles I get buying seed in packets.

albert 135:

Grow those ones in seed packages and save the seed for a few years and I guarantee they will be just as tough. Seed from seed companies comes from plants that have been babied notgrown outside and left to their own devices. The survivers of ones grown outside are the toughest of the tough and their seed is also