Jacks are ephemerals and mine are starting to die down, though I have some that are just popping up as well. The spathes will produce clusters of "red" berries which can be placed in the ground as soon as they are ready. Peel the outer red pulp off before you put them in the ground. Either wear gloves or do your best not to touch the outer coating as it can cause an allergic reaction in some people.

Jacks are NOT ephemeral in zone 5. Mine persist until fall.

Mine persist to the fall too (USZone5) except for the ones which are in sunnier dry areas. I don't bother removing the seed coats -- I just sprinkle the berries on top of the ground in the fall and cover them with leaves, and I've had good germination this way.

My bad, the jacks in my yard with spathes do persist until the fall.

great! i'll look for the spathes this weekend. so should i remove the berries and hang on to them until the fall? i just looked up spathe on google...

so it looks as though the spathe on my jacks are fading. is that normal?

it's too bad, because it was a real treat to see (this is the first time i've seen jacks), and wanted to show someone, but the spathe was gone!

--robbie--

I have a Jack in my front perennial bed. Would you believe I had at least 50 seedlings. Every seed must have germinated. This is the one that bloomed again last fall in our crazy weather.

Yes, the spathe fades and the berries form. The berries don't fully ripen until the fall (when they are ripe, they are are bright red and come off the stalk easily). At this time you can do nothing if you want seedlings around the jack, or remove the stalk and scatter the berries elsewhere and cover with leaves. As someone else mentioned, you can remove the red seedcoat -- many books recommend this -- but I've never bothered doing this. Jacks seed around in Nature without anyone removing the coat.

I should have mentioned that if your jack is young, it may not produce berries even though it flowered. The youngest plants don't bloom, then they typically bloom for a few years but no berries, and then they start producing berries. Eventually the common jack can get to be almost 3 feet tall and produce a lot of berries. They are long-lived plants (perhaps even a 100 years!)

thanks for the info, lisa! can't wait until it reaches 3'! i'm not sure of the age of these. we received them last year from a woman who gardens in queens, and brought them to our house upstate and planted them. at that time, i think they were already dormant? we have three of them --- and they were about one foot tall. in fact, they were hidden by some mayapples. they looked great, though! i'll keep an eye out for the berries. hopefully we'll get some!

i just did a google search on "Arisaema"... this will keep me occupied for a quite a bit!

thanks for all the info!
--robbie--

my friend an i are doin a science fair project but we dont know if the plant is blooming now so we can feed it to mice and see how they react to this medicina plant.

Wow. Really? Pick another project. This just sounds mean and cruel.

I suggest you read the "hazard" section in the PFAF datasheet on jack-in-the-pulpit. It's not lie. I've known people to taste "indian turnip" aka jack-in-the-pulpit and according to them the sensation makes the warning noted look tame.

Show a little compassion to the living beings around you. The compassion or the pain you put out into the world will certainly come back to you so let it be compassion.

FataMorgana

Here is a link that might be useful: PFAF - Arisaema triphyllum