Lysimachia Species, Circle Flower, Yellow Loosestrife

I also live in zone 5a and it is in heavy clay and doesn't escape or go anywhere, but in the place I planted it. It has doubled (the clu...Read Moremp I planted the first year) in 3 or 4 years, but certainly is not invassive or taking over my garden - now the agastache, bee balm, and other plants in the same bed are definitely going crazy and taking over the bed, but not this one - so I recommend it to anyone with heavy clay soil! It seems to love it and stay in it's place there. See picture of mine - that's all there is and it isn't too much bigger than last year.

I got some of this from a fellow gardener, and she told me it would spread. That isn't what happened at all. I planted it along a borde...Read Morer and something just started to eat it up. The leaves were full of holes like what Japanese beetles might cause, but I never saw a beetle near it. It started to wither and die, so I dug it all up. I had another variety of lysimachia planted near these, and that died too. No other plants in any of my gardens had any problem like this. Did a little research and I think the problem could be sawflies, and they seem to prefer loosestrife. So I think I did the right thing by eliminating the plants.

Yellow Loosestrife is not invasive in the Seattle area, that's Garden Loosestrife, two different plants. In my partial sun garden yellow...Read More loosestrife puts on a dependable long flower in the summer. It does spread, but very gradually and is easily controlled by pulling it, its roots are shallow.

Yellow loosestrife is very pretty right now (June 30) here (Zone 4/5), but I would suggest planting it with caution. It spreads steadily...Read More, though not like the real cancers of the garden, creeping harebell or snow-on-the-mountain/bishopsweed. I'm removing it from our garden, despite its pretty face, because I'm tired of dealing with invasives.

I have had this plant growing in full shade with good drainage for 4 years. It flowers reliably and does not spread under these conditions.

This plant showed up in my yard and is now growing widely along the edge and into the woods, looks to me like it's out-competing the resi...Read Moredent bunchberry. I don't have any near neighbors, so this plant must have come from some distance away if it escaped from somebody's garden. I'd be very careful with it!

davidlbangs, when I google "Loosestrife eradication", as you suggested, I see references to purple loosestrife, Lythrum salicaria....Read More (Note that "loosestrife" is a common name, used for plants that are in completely different genera.)
If there are sources that indicate that Lysimachia punctata is a serious invasive threat, it would be useful if the references were posted.

Not proven invasive in Maine. Puts on a show twice a summer and shallow rooted enough to control. Dead heading is a must in controlling t...Read Morehis plant so it gets clipped before second bloom and afterwards. If I have too much it gets traded or composted.

This pretty plant is taking over. It is the ultimate "volunteer", showing up in the middle of rose bushes, above our rockery, etc. It i...Read Mores the most aggressive weed we have here on Lake Sammamish, near Seattle. King County is undertaking a "Yellow Loosestrife eradication effort" which entails public meetings and letters and postcards sent to all lakefront homeowners asking them to eradicate all Yellow Loosestrife.

Searching for "Loosestrife eradication" on Google, I see that this is not uncommon. Governments are aggressively trying to get rid of yellow loosestrife in various regions.

Why the heck would anyone buy an aggressive weed that can't be controlled? Shouldn't your neighbors have some say in whether to have this sprouting all over their yards?

I encourage Dave's Garden to stop promoting dangerously invasive plants.

I had grown mine in full sun about 7 years ago. During the second year, I had ripped out most of it, because of it's invasiveness. The ...Read Morethird year, I removed it completely and potted up a small portion. The fourth year & fifth year, I still had some new shoots, but were easily removed. The fifth year, which was potted for a year, overwintered with no problem. I then transplanted it into full shade. Year six, it had still spread considerably, although the height is definitely less than it was in full sun. Still, it thrives with no sun and the only water it gets is from rainfall; no supplemental water. This one is kind of tough to get rid of, and even tougher to kill.

Hot year, cold year, rainy year, sunny year...this garden perennial never waivers and always puts on a reliable show. I've had it plante...Read Mored for 8 years and although it has a reputation for "escaping" and becoming invasive in other gardens, I've not had a problem in our heavy clay soil. I have it planted at the top of my hillside garden where the drainage is good and it has "stayed put" and only increased it's perimeter modestly each year.

Just wanted you to know that it grows well in Washington state also. Planted it a year ago, lost the tag and couldn't remember what it w...Read Moreas called until I found your website and then identified it. It looks great in my garden - so bright and yellow but think I will need to keep it within better bounds as I can see that it would like to take over!

I have found that Lysimachia does very well in zone 4. Over winters very well. I have not found it to be invasive. It stays in nice clump...Read Mores that do get larger each year, by suckering, but also selfseed. I find it to do well in either shade or full sun, but requires a bit more moisture in the full sun. Transplants ealily but needs to be well watered until established and can also be started from seed. By seed in my zone it take two years to get a nice little clump.

This plant is a great flower to add filler in a flower arrangement, this definitely is a positive but then it throws its seed around whi...Read Morech is then a negative.But the seedlings are easy to hoe out. But is not a spectacular showy plant.

Great perennial for height, foliage color & pretty, small yellow flowers that bloom from late June to September. The variety I have has d...Read Morearker leaves & is a nice contrast with other perennials. Can be grown in sun to part-shade & no special soil requirements that I've encounted. Disease & pest resistant in my experiance as well. Not sure if it reseeds itself or suckers underground, but new plants spring up in the spring a bit away from the mother plant. Just lift & plant where more is wanted. Transplants very easily. Keep new transplants well watered until established.
Over-winters very well in my Southern Ontario zone 6a/b garden.

This plant thrives for me in our Ohio zone 5 gardens. I have it in partial sun in both beds and it has overwintered well for us, too.