Shiso

Why to heck is shiso so hard to grow? I got some at a nursery one year, it self sowed and came up again the next year, but I can’t get it to start, or thrive if the seeds hatch.

I had one good year with it, but that’s it. I think it’s just fussy, like basil.

I have some luck this year, out of a batch of seeds (like 8) that I’ve sowed indoors with a heating tray under light end of March, took, 5-6 days to germinate (just checked my notes), I’ve 3 plants. Now they are growing happily outside. I remember I’ve tried sowing another batch of seeds (not the same source from ebay) the year before in April, nothing came out.

I guess shiso is sensitive to germination conditions, but once they’ve hardened they survived the awful weather. This year there was a sudden drop of temperature for a week and lots of rain for another 2 weeks in May, the batch of basil and dill that I planted out in mid April, the same time as Shiso, didn’t survived, which normally I consider them relatively easy. Shiso seem to be quite sensitive to fertilizer too, I see some deformation in leaves (the lower right leaf on the photo).

A year, I bought an established one, purple colour, from the plant nursery, it was such a dashing plant, everybody asked about it. I believe most people grow the green ones.

@ewsflash I’d blame the seeds, maybe try again from a reliable source?

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I never even thought to try growing shiso myself, and I cannot find it anywhere in my hood for recipes where it’s called for. I’ll have to hunt for some leaves. Do these grow into fairly tall plants?

Same here. Several sushi places use it as a garnish and I always ask for more. Sometimes I eat there but often I take it home for later.

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Ok I check my plants again, in fact the leaf distortion is only limited in one plant, not the other 2 plants, can’t be a fertilizer problem.

About the same size as basil, in my limited experience.

They are a bit bigger and taller than basil, at the peak of summer.

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Hence my limited experience- thanks, naf.
Do they also grow in the same general conditions as basil (soil, sun, water, etc)?

Yes. And I would say it’s easier than basil. Actually, perilla (shiso) is in the mint family.

I read that after a few weeks’ sun, when the plant is getting mature, you can move it to a partial shade. I’ve never tried that but kept that in a sunny spot all the summer. The plant will die in late autumn or early winter. I’ve heard that it can be overwintered, which I might try this year, if the plant is in good shape.

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I saw on a plant forum, they said seeds have a short shelf life, about a year.

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Shiso is a weed out here! I see the red form ( also known as Perilla crispa) growing by the roadsides and it can self seed like mad.

Shiso, Perilla frutescens, does have some quirks. The seed germinates better after the dry seed has been frozen for a while. Light is generally needed for germination, so press the seed into the soil’s surface and keep it misted. After a day or two in the sun, getting light, it can be barely covered. The light and cold deactivate germination inhibitors. Eventually, the inhibitors break down, but it might take a long time without the cold>light.

Shiso isn’t crazy about being transplanted, so sow the seeds where you want them and thin them to around 12-18 inches (30–45 cm) apart. A well-draining, rich soil that is SLIGHTLY acidic, pH 5.5–6.5 works best. The more you harvest, the more nitrogen-rich fertilizer it will need.

Shiso plants tend to be short-day; as the day length gets shorter, it’ll start going to seed, so plan on harvests while the days are long or grow it under strong plant lights.

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That’s good information, thanks. I must say I’m a little envious of your shiso abundance. You live in the southeast US, don’t you? Sigh- this time of year is the absolute worst to try some. it’s hitting 100 every day with just about no humidity at all for the near future, so I’d have to stand outside with a misting device all day. I have some seed from last year, guess I’ll put it in the freezer until we start getting rain- IF we get rain- and try it again. I understand the seed is probably too old to germinate, but nothing ventured, nothing gained.

I have quite a few volunteers from previous years. Didn’t know it was tricky to grow.

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Yes, I’m in Virginia, the foothills of the Blue Ridge Mountain. Perilla/Shiso has become a weed of concern in many states around here, since it’s super common and toxic to cattle. The weedy form pops up everywhere on the property here, it’s routinely pulled up.

Ironic ewsflash, you want to grow it and can’t; I don’t care for its flavor and it’s everywhere!

Keep the seed in the freezer until early next year. If planted now or later, it will start to flower and go to seed. Unlike basil, giving the plants a severe cut-back usually doesn’t result in lots more foliage.

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Weed of concern- if only.
My cousin that does landscaping in Illinois can’t believe I actually buy viola odorata plants, considers them weeds and kills them. Here they take a lot of care to live through summer and come back the next winter.
Thank you for the growing instructions. I’m going to go buy a couple of packs and throw them in the freezer along with the current seed until next February or so.

I suspect your cousin is actually killing Viola sororia, the Common Blue Violet, not V. odorata. The latter isn’t reliably winter hardy in cold climates and the former is a widespread weed.

If having shiso is a goal, you could consider an indoor plant light, set to a daylength of 12 hours to delay going to seed. I suspect a modestly-sized LED could produce quite a supply.

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In central New York, my shiso has self-sowed in a window box for 2 years now, but only green.

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You’ve reminded me that I bought a grow light a year or two ago. My husband tried it out, said it was too bright (for what I couldn’t tell you), and put it in the garage. Now I have to go find it.

OMG, there’s Shiso coming up all over the place here! I’ll have to take some pictures from the border areas where it’s not getting weeded. Too bad I’m not that fond of it…yet.

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