What variety of artichoke do I have?

Several years ago I bought an artichoke plant from a guy at my local farmer's market. It has since multiplied into several plants. The flowers on these plants always turn purple on the tops when they are very small and they start opening up when they are around tennis ball size.
Does anyone know what variety of artichoke this is? Is there a variety of artichoke that would be better for me? I am in Sunset zone 22 very near the edge of zone 24, about five to seven miles from the ocean.
Would Imperial Star artichoke grown from seed be better than what I have? When would I plant Imperial Star artichokes in my area? Thank you in advance for all replies.
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My previous cat Rocket thought that every time I ate something he
should get some canned cat food. Marmaduke, the cat I have now,
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Are you sure it is an artichoke and not a cardoon (Cynara cardunculus)?
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No, I am not sure. How can I tell which it is? Would you like me to email you pictures of them?
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should get some canned cat food. Marmaduke, the cat I have now,
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Daniel Prince wrote:

Its not so easy to distinguish between the two. Cardoon seedlings and and young plants are generally more vigorous in growth, the leaf a little wider and has a more metallic, silvery sheen. There are many who would suggest that the ribs of the young spring leaves make for very good eating (look to Italian recipe books for more info) but it is generally accepted that the buds are not as useful. The excellent book "Vegetables" by Roger Phillips&Martyn Rix (the Pan Garden Plants Series) has a very good section on artichokes and cardoons. I have grown the Imperial Star artichoke from seed and they give a very nice even line of plants without the thorniness that often comes with other varieties. My 4yr old plants are still cropping very well both spring and autumn. Hope this is of some help - Connie
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