Pyrethrum in Montana

Can Pyrethrum be grown in the Flathead Valley of northwestern Montana? If so, what are the water requirements and how expensive is the seed?

We are not sure that pyrethrum would be hardy in your area. The crop is grown commercially in Kenya, so obviously it thrives in warm areas. We do know that the species is hardy to zones 4-9, but the high pyrethroid strains probably are not quite as hardy, perhaps with a zone rating more like 6-9. Montana is well below zone 6, so overwintering of the crop could be unreliable. A small trial plot is definitely recommended before scaling up to commercial production.
We recommend growing the Certified Kenyan strain of pyrethrum. This is the most important strain that is grown for the commercial pyrethrum market. Unfortunately, in 2000, there is no seed available due to crop failure. We are hopeful that new seed will be available in 2001 or 2002.