Judy, sounds like a great and distinctive plant. The answer cames down to degree of control. You could isolate this plant and totally cross by hand, or isolate, and let nature cross by insects, wind, etc., or allow it to cross with the others. In any instance, the parent plant will pass on the gene for all purple foliage, and a percentage of the offspring should exhibit that trait. Even if none of them do, the gene is still present. Whatever you choose, I would save all seeds from this plant and select the purple leaved kids to cross to one-another for hopefully ever greater occurance of the exclusively purple leaf.

line breeding- best to keep plants with purple leaves to themselves to 'fix' trait ie. purple leaf variety. do hand pollination to rule out natural crosses that may taint your efforts. keep only purple leaf seedlings and cross purple with purple to stabilize genetic strain. hopefully with diligence you will get higher percentage of purple seedlings until they all come true from seed, so that they self sow without reverting to green or spotted forms. lol.
big john

Hi Judy, Good advice from Michael and Big John. Frankly, if I discovered such a plant in my garden, I would ruthlessly weed out the other Lunaria to prevent cross pollination. Would try to minimize the risk of losing this trait before it becomes established. As you said, there is a time factor to consider- why take chances with a potential Plant of the Year?! John

Some of the greatest plants come from sports and flukes. I would try to propagate cuttings ..as many as possible without harm to the parent plant. I have never tried rooting Lunaria. I have rooted many that was said could not be done. But I would not leave only the one plant to fate. I would try to clone more. Would be great if you had someone who could tissue culture.

Thank you to everyone for verifying that I should do something about this plant! I did not know how excited to get about it.
The real excitement will come if I can be successful with some of your suggestions.

I found a Tissue Culture "recipe" for home gardeners on a web site and wondered if anyone has ever tried it. I have the sterile things from the hospital where I work so that will be the easy part. The difficult part, still, is the limited amount of plant material to work with.

Judy

Here is a link that might be useful: tissue culture web site

Here is a page with some more great tissue culture links! John

Here is a link that might be useful: Tissue Culture Index

...JUDY...get excited now...LOL. You are further along than you think. Purple leafed anything is extremely popular. I agree with John stableize it and you could have the plant of the year.....................Jim

I have the purple leaved one too.It came up this year from seeds of a planting that is three years old.Does nayne think the seeds will reproduce another purple leaved wonder?

I talked to Dan Hinkley at Heronswood and first he said, "Give it to me!" Then he laughed and said no, but to isolate it and collect the seed and sow ALL of them, then select the best seedlings and do it again and try to get a strain going.

However when I pulled out all the other plants (I did transplant some about an acre away) some of them came back in their original spot from ROOTS! I did not expect that at all. I thought I would try some root cuttings from the parent plant and see if they make it over to another year..?

Btw, the flowers on this plant were much darker and brighter and have a white eye--really stood out and drew lots of comments.

Sounds exciting!
I'm fairly new to plant breeding but have read that Brassicaceaes (Lunaria's family) can be strongly self-incompatible. There are some reasonable simply ways around this such as pollinating in the bud stage. More info can be found in Carol Deppe's "Breed Your Own Vegetable Varieties"
You could also allow it to cross and then select form the F2 generation. This may be easier. I would try both.
By the way both root and stem cuttings should be easy as per your root experience.
Hope this helps, good luck.

i dont know of the plant in question some plants strike in moist sand as well or better than in tissue culture if that helps. but bury them 6 ins deep completly burried and if they strike use bottle method to slowly aclimatise kevin.

Sounds neat. I recently asked Frank Morton about a similar problem, and he said that in the instance of incompatability to cross with something else similar, like on a hybrid kale (hybrid means all plants have identical genomes) cross with a pure hierloom.

Carol Deppe's book is great. I have gotten into correspondence with her about plant breeding.

Billy

Hi Judy,
I am just starting to research Lunaria (Purple Leaf). My 8 year old daughter, Holly has just grown 100 plants from seeds donated by H.R.H. Prince Charles. She is doing this as part of her Brownie Gardening Badge + Fund raising for our local church. She sowed each seed individually during April this year, they seemed to take 4 to 5 weeks to propogate. They are now at various stages of development. We were worried a couple of weeks ago when some of the leaves developed mottled black spots but then realised the leaves were turning purple. Sorry I can't answer your questions, but its interesting reading the responses you have had. I will let you know how our plants develop and if they survive.
Regards
Andy2004