Is anyone growing Tansy (Tanacetum vulgare) in the SouthEast region, zone 7-8, NC/SC? Tansy is supposed to be a good companion plant for basically any fruit tree you can think of, as well as a number of ornamentals that suffer from pests. I am reading that it's deemed invasive in some states, and otherwise is said to be aggressive spreader. However, I read the same things about both Yarrow and Valerian, and my experience with them has not been that dramatic at all. In my heavy clay soil, Yarrow seems to crawl around a bit, but it is extremely shallow rooted and is very easy to pull if needed. I was worried a bit about Valerian when planting it about 1.5 years ago, but none of the worries came true. While it maybe an aggressive spreader up North, here in Zone 7b it is pushing its tolerance for heat (I think). My three original plants produced two very shingly new ones this year within a foot from their base, that's it. I did allow it to go to seed last year, but found not one new seedlings so far..
So I was looking to see if anyone has experience growing Tansy as a companion plant for their fruit and berry plants in this climate, and how big of a "spreader" it actually proved to be? Does it seek new grounds to spread out, and if so, how far and how fast does it move? Once established in the spot, is it difficult to remove?
In my research, Tansy consistently comes up as a repellant to ants, flies of all kinds and mosquitoes. I like how Tansy's properties are summarized in the book "Secrets of Companion Planting for Successful Gardening" by Louise Riotte:
"Tansy is considered poisonous to humans and to cattle ... but planted under fruit trees, particularly peach, it repels borers, and is a good companion to roses, raspberries, blackberries, grapes and other cane fruits. It deters flying insects, Japanese beetles, striped cucumber beetles and squash bugs, helps repel flies and ants. The dried leaves are useful for storing woolens and furs. ... The plant contains volatile oil, wax, stearine, chlorophyll, bitter resin, yellow coloring matter, tannin and gallic acid, bitter extractive gum and tanacetic acid (which is crystallizable) and precipitated lime, baryta and oxide of lead. Because of its concentration of potassium, tansy is useful on the compost pile."
They weren't very bright, but they were very, very big. Ad contrast:
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