I've never stratified catnip seeds, but they've taken several weeks to germinate and that might be why. If you have enough seed why not try them both ways? Soak and plant a few now and in the mean time try the freeze/thaw method with some and see which germinates better.

Thanks, at least I know the terminology now. Stratify. If I Google "stratify catnip", I come up with instructions to freeze for a few months, a week, and even (http://www.gardeningknowhow.com/herb/growing-catnip.htm) to freeze just overnight. At least one reference says keep warm and moist for a few weeks before freezing. That sounds kind of daffy, as if the plant starts to germinate, you'll simply kill it off.

This can't be that hard to understand. Well, I guess while I'm trying to figure this out, I might as well keep 'em in the freezer!

The idea of doing an experiment seems smart, but over a time scale of a few months, there are too many other variables.

You could also save some of your seed to winter sow. I've been growing catnip in the same hanging pot for a few years. When it flowers and goes to seed, the wind blows the seed to the ground around the front door. In late Spring I have catnip sprouting all over the place along the walk and in the hanging pot that I usually just store on the ground for the winter. There's so much growing that the cats can't kill it. The seeds survive below zero temps and all the salt that we have to use on the walk. The plant in the hanging pot doesn't grow that well because it's cramped, but it flowers early and gives me a steady supply of seed.

Good point. Maybe I'll do that. Just sow twice. I just want an indoor plant (which will have protection from my indoor cats!) and I suspect it won't be too long before it is pot-bound. So the issue really isn't the outside temperature, though starting seeds outside in 8b in August can be a dangerous proposition.

Catnip likes full sun. Indoor culture is going to be a tough one to manage. Can you have your container outdoors once you get it started?

FataMorgana

But partial shade outdoors does not equal indoors in regards to lighting.

Yes, I've had catnip grow in partial shade as well - it is wild at my place and grows where it wishes. Where it most wishes to be is my Western NY State full sun. Take whatever you wish that to mean in regards to sun in Texas.

Catnip grown indoors, unless you give it extra lighting and maybe not even then, will be puny and weak compared to a plant grown outdoors.

FataMorgana

Thanks. I appreciate the advice. Points noted.

Yes, the phrase "full sun" is taken, here in summertime Texas, as sort of an inside joke in the gardening world. When the temperature is over 100F in the daytime, and gets down to the high 70s at night, the last thing you want to do is to put something in "full sun". Well, maybe for half a day, well mulched, and watering every two or three days. I've gardened in the Pacific Northwest and California, and "full sun" means something totally different there.

FWIW, I read in a Canadian gardening blog that one way to stratify seeds is to moisten them, perhaps by just putting them in a plastic bag with moist soil for a few days, and then chill them in the coldest part of the fridge for a few days. DO NOT FREEZE.

Now that makes a lot more sense than hydrating them and then freezing them which is what I saw recommended somewhere else.

I've been trying to remember if I've grown catnip from seed, but I can't recall. I was curious about the stratification and saw that more than one source didn't include cold stratifying the seeds in their instructions. Here's what seedsavers.org says to start catnip:

Nepeta cataria (Catnip) - Planting: Sow indoors just beneath the surface of the soil 8-10 weeks before last frost. Seeds will germinate in 7-21 days. Plant out in early spring when a light frost is still possible. Best grown in full sun or partial shade.

FataMorgana