Saponaria/ Soap wort. Need to know more

devon, United Kingdom

Hello, here are my Soap wort plants which I grew from seed at the begining of the year, in the UK . Are they perennials? Will they survive the winter? Do I cut them back before the frost just like i do with my primroses? Need to know lots as I'm still learning. Thank you for looking

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Casper, WY(Zone 4a)

If you are talking about Saponaria ocymoides, yes it is a hardy perennial. Your plant don't match the name. Saponaria ocymoides is a creeper with pink flowers and smooth heartshaped leaves. Your plant look like it grows upright.

I cut back all my perennials in the fall maily because I don't have time in the spring. This also gets rid of bug eggs that may be attached to hatch in the spring. It also looks neater and makes raking leaves easier.

Deep East Texas, TX(Zone 8a)

Are you intending to move the container indoors for winter? The reason I ask is these will be more hardy when planted in ground. Their roots will be more susceptible to freezing in a container.

I don't know your temperature lows but the Saponaria ocymoices spolendens (soapwort) is hardy for temps to -10F below 0F.

Yes, they will be perennial. Mine are in ground and I never cut them back. They tend to sprawl and spread out.

Blomma ~ I think the reason this plant doesn't resemble the Saponaria plant is it has been nurtured in good soil with good moisture. A soapwort plant, in ground and grown hard will look differently but yes, I do believe that is a correct ID.

I am impressed that these are grown from seed. Most folks will start with cuttings or plants which are dug up which is far less of a challenge.

This is a link to the DG PlantFiles on these plants including photos if interested.

Casper, WY(Zone 4a)

nutired in good soil would not change the growth habit which is in the genes. In other words, a creeping plant would not suddenly start growing upward due to better soil. If anything it would creep faster. I too started mine from seed because I never saw it offered for sale. I used commercial seeds.

I am in zone 4 with winter temp sometime going down to -30 degrees, average -20 and it survives.

(Pam) Warren, CT(Zone 5b)

My saponaria looks like that when it starts growing in the spring, then flops as it gets taller. My clumps are more dense, though. The ones in the picture look like separate plants. And they are completely hardy in my zone 5. In fact I rescued some white saponaria from an untended area of vinca and invasive weeds that must have been there for many, many years. I've read -from the classic British gardeners, actually-
that Bouncing Bet, a common name for it, is one of those plants that once you have it, you have it forever. I think you don't have to worry about it.


Deep East Texas, TX(Zone 8a)

I am still comfortable with that being a young, well grown Saponaria. The leaf structure is the indicator to me. And I agree with Pfg, it will start to crawl with age. There is an old adage that in the first year perennials leap, the second year they creep.

Mine was an heirloom, an unidentified passalong received in 2005. I don't have a close up of the leaves but the first photo was when it was newly started in ground at my house. The second was a bloom when I was searching for an ID.

By the end of our summer it looks terrible but it has never failed to return. I mulch it for winter although it never dies back in this warmer zone.

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Casper, WY(Zone 4a)

podster your is correct. Mine began crawling as soon as it sprouted and started to grow. They are only upright in the early stages before the stem becomes too heavy. Saponaria stems are thin, never thick and would not support upright growth past infancy.

first year perennials leap, the second year they creep

not all plants. growth habit is locked in the genes. .

Calgary, AB(Zone 3b)

The plant in question is Saponaria officinalis. It and most other Saponaria spp. are very hardy (I grow several alpine species here).
It would probably winter over without problem even in a pot, in such a mild climate as Devon's.

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