Hi April,

First of all, if it helps, you're not alone :-) I've always had problems getting Cleome seeds to germinate. When I do, the germination percentage is always pretty low. According to the University of Wisconsin, Cleome seeds need day to night temperature fluctuations (see link below).

This year, I tried putting the heat mat on a timer that turned the heat off at night and back on in the morning. However, I only got a few degrees of temperature fluctuations that way and it didn't really seem to make any difference (still poor germination).

If there's a way for you to get a day to night temperature fluctuation of at least 10 degrees, you might have better luck than I did. Next year I think I'll try winter sowing the Cleome.

Hope this is helpful,

Art

Here is a link that might be useful: Germinating Cleome Seeds

Thanks Art! I sowed cleome seeds in garden bed 2 weeks ago and temps have been in 70's daytime and 40's past few nights. Maybe a few will germinate. My mom used to have cleomes and they self sowed everywhere. I think I will try to winter sow some next year also. Good luck to ya!

Cleome is really easy to grow. This is how I do it. I rake the dirt lightly. I drop the seeds on the dirt and press it. I cover them very lightly with the dirt. I mist them twice a day.

I definitely think starting them outside is the way to go. I have tried them several times inside, and get few to none. This year I even tried putting them in the garage to freeze for a few weeks, then brought them in and put them under lights - but that didn't work for them - (Columbine & Spinach liked it though). They have never self-seeded for me, but fewer things do here in WI.

I am going to try Virtuosity's method today! I really want some cleomes! Haha

Don't lose hope, they take time to germinate maybe a week to 10 days. The shape of the cotyledon is long oval. Again, don't use strong water, it might wash away the seeds. They're small :)

Cleomes reseed heavily in my beds. I can remember trying to start them ahead of time indoors without much success.I think sowing outside is the way to go.I find them easy to transplant even fairly large.
rose

How I grew the seeds: I planted them in trays outside. The trays were only taken in if a freeze was threatened. Burned in my memory is an old book on germination which discussed how some plants need significant weather fluctuations to germinate. It discussed Cleomes as it's prime example.
Maryland and some other states call them invasive. So I guess if you can simulate the swings in Maryland's winter/spring temperatures you could get success.

715Rose 's point is excellent.

I have two groups of cleomes grown from seed. One, the classic Queen cleome ; the second are seeds from the new Sparkle which is thorn-less. I plucked the seeds off a Sparkle plant, so my seeds are not the first generation of this F1, so will see if they produce thorns or not.

Incidentally the young plants apparently grow slowly like pentas.

Here is a link that might be useful: Sparkle

This post was edited by bugbite on Sun, May 26, 13 at 15:53

I have a handful of cleomes that have sprouted today! Guess I was giving up on them too quickly. Thank you for all the great info.

I winter sowed some queen cleome seeds. They were doing pretty well (germinating at least) when... I sorta dropped the container they were in. They (and the lupines) were the seeds I most anticipated growing so I thought the world was going to end ha ha. Then I got some new dirt, stuck a few seeds in (one container surface sow, one 1/4" deep) and viola... both are growing. I just brought them inside at night, once they sprouted, if it got below 40-ish. Now, how many will survive or bloom this summer I don't know but... different story

My cleome seedlings have a purple reddish tinge to them and are growing very slowly...thinking they may have been bit by the cold but are not dead?