Yes, these are difficult plants that I struggle with, too. I think that my soil is too sandy and fast draining for French Tarragon. Ideally, a deep loam would be better. All of the lavender plants I have grown, have died during the winter. I believe that my zone 5 is too cold for them.

Rober49,

Those are two fine herbs worth working on. I'm further north than St Louis and here all I have to worry about is soil drainage, parched summer soil, soggy spring mud, decent sun exposure, and bitter-cold dry winter winds.

Can you describe your bad luck and your experiences? Meanwhile, here is some anecdotal wisdom that might set you on the middle ground.

Tarragon dies down around this time of year. It will come back strong next year. Tarragon grows like a weed around here, and it does not mind clay soil or soggy conditions (by NE standards). It does not like getting too dry in the summer though.

Lavender in general is pretty tough especially when planted in the ground. Winter hasn't hit yet... so what could have prompted you to have lavender problems?

I almost lost a stack of lavender because it was too dry in pots over the summer. Easier and more mysterious is losing lavender because of too much moisture.

To make the sad ones happy I had to repot them with some clay and make good air flow around the young branches. Lavender tolerates drought up to a point.

My healthiest lavender plants are the ones planted in the ground. But, a good amount of the young ones have a hard time or die in the spring after a long winter.

there's a local plant a nursery that tried to pass off a plant as tarragon that did grow like a weed but it had no smell to it at all & grew tall & spindly. the true French tarragon that I've found in nurseries I've tried planting in all sorts of soils & conditions over the years & it just dies. it rarely makes it thru the summer. maybe i'll try some from seed next year. the same has been true with lavender I planted some this spring & it was dead by july. it makes no sense. I use a lot of tarragon when I cook. the lavender besides being a lovely addition to the garden is a long term bloomer. i'm always adding plants that bloom long term & are attractive to honeybees. the hyssop, Russian sage, oregano, salvia,borage, & cosmos in my yard are a steady source of pollen & nectar. a patch of lavender would be a great addition. bottom line is I'll not be giving up. this mild weather is keeping some plants going. my Russian sage, cosmos, hyssop, & salvia are still blooming & the girls are still foraging on them. I even picked a tomato this morning.

Unfortunately you cannot propagate French tarragon from seed. This is the Russian one and does not compare. I have no problem with Lavender and I grow them in rockeries but French tarragon, I killed yet two plants. It looks like it wants the same growing conditions than lavender but it doesn't.

There's a marigold that

Grows easily in climates where French tarragon struggles. The leaves of this marigold are just as good as French tarragon , maybe even better, to cook with. It also dries beautifully and retains its excellent tarragon flavor. Can't think of the name of the marigold of hand - it's perennial in zone 8 and 9. And maybe 7 too. Get this it is every bit as good as french tarragon and easy to grow. Do not confuse this marigold with Russian tarragon which is worthless to cook with.

is Russian tarragon tall & spindly & spreads easily? maybe that's what one local nursery was trying to pass for the French. it was worthless period. you piqued my interest so I searched 'marigold substitute for French tarragon' & found these:

http://www.examiner.com/article/mexican-marigold-herb-fine-substitute-for-french-tarragon

http://www.bing.com/news/search?q=Marigold+Substitute+For+French+Tarragon&qpvt=marigold+substitute+for+french+tarragon&FORM=EWRE

The marigold newtie is referring to is Tagetes lucida and is known by common names such as Mexican mint marigold and Texas tarragon. Although it truly is a marigold and will produce small, simple flowers in zones with suitably long, hot summers, the taste & fragrance are dead ringers for French tarragon & may be used exactly the same way. French tarragon does not seem happy south of the Mason-Dixon line, so get some of these marigold seeds for spring. I am sure you will be very happy with the results! It also dries very well and retains its culinary properties as well as the real deal. See: Texas tarragon

The key for bringing lavender through the winter seems not so much the cold but the need for excellent drainage, as the roots cannot tolerate wet soil. I finally was able to bring my lavender through the winter by planting in raised beds in leaf compost amended with some very coarse sand and even mixed in some sharp gravel and rocks around the root zone.

I cannot even get lavender thru the summer!

Tarragon does great in containers, I have never bothered to plant it in ground.

I put tarragon in the shade of citrus and fig trees, in soil full of nematodes and it's spreading like crazy. Stayed alive all winter, oh, wild fennel and cabbage are loving that spot too. Maybe grow it near the roots of a deciduous tree is the key? It's a fluke because tarragon is not supposed to grow in my area.

My tarragon grows in full, hot sun, in a raised bed of very sandy soil. I never do anything with it except cut it back. I never water it because it gets all it needs seeping down from tiers above it. When it's a really hot day, it wilts a bit, so you've probably got it right, Mavens, keeping it shaded. I don't have that option. And it still grows rapidly.

the 1st problem I've had with French tarragon is finding real French tarragon. I bought some a couple of times that ended up being invasive weeds. when I have found it, it croaked. I will try again

Yes, this is what we all were discussing a bit earlier on in this thread in response to your post in November. You likely had Russian tarragon which is indeed a weed! True tarragon, as pointed out above, does not set seed. That nursery is not to be trusted! They should not be selling that "fake" tarragon. I would tell them so & likely never shop there again. The site linked below discusses all three plants called tarragon. However, the author of the article claims all three share the same rich flavor & scent, which I find misleading. Interesting article, nonetheless. The 3 tarragons

I've tried tarragon several times from cuttings. It doesn't seem to tolerate summer heat in Georgia (or Florida when I lived there).
This year I have ordered seeds for "Mexican mint marigold" AKA sweet mace. From what I've read online, that plant does much better in summer heat, and the leaves have similar flavor to French tarragon.

Yes to both of the statements in your last sentence, Common Cents. I have grown and used Tagetes lucida as well as French tarragon for years in several different gardens. The flavor and scent are not merely similar; I doubt you could tell the two apart in a side-by-side blindfolded test. I am confident you will be pleased with it.

I'm not throwing in the towel on French tarragon BUT my Mexican marigold seeds just arrived in the mail.