JayPoc
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cold hardiness of carrots

hello all. I wanted to get everyone's experience with regard to cold hardiness of carrots. We're having something of a warm snap, and it looks like it's going to rain frequently over the next week or so. In light of that, I figured I'd sow some carrot seeds. I had given up on ever growing them because invariably the slugs have wiped out my seedlings before they ever had a chance. This year, I decided to give it a go again, but in containers. While the forecast for the next week or so shows low temps above freezing, we surely will have many freezing days in the future (our 90% last frost day is in early to mid may). How cold would it need to be in order for me to feel compelled to move my containers indoors?

Also, how about parsnips? I held off on planting them because the package seemed to indicate they needed it warmer. I thought they were about the same as carrots?

Thanks!

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applestar
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This sticky thread is good for figuring out what temperatures are good for starting seeds, and parsnips are one of the lowest temp germinators --

Subject: DigitS posted a great link for seed germinating temp/time
applestar wrote:Subject: Temperature & the time it takes different seeds to sprout!
rainbowgardener wrote:I posted this once before, but here it is again:


https://tomclothier.hort.net/page11.html

scroll down a bit to the chart:

Percentage of Normal Vegetable Seedlings
Produced at Different Temperatures

so reading across the tomato row: (degrees F)


Soil Temp 32...41....50..........59.......68........77.......86......95....104
Tomatoes 0.....0....82(43)..98(14)...98(8)...97(6)...83(6)..46(9)...0

so at 32 and 41 deg, none of the seeds sprouted. At 50 degrees 82% sprouted, but it took them 43 days to do so (!). At 59 deg, there was almost complete germination by 14 days, at 68 it took 8 days and at 77 only 6. At 86 deg, it still took 6 days, but germination percent is beginning to decline again.

Of course YRMV, but this gives an idea of the effect of temperature on germination rate and percent.

There's another thread with links to winter hardiness somewhere -- I think it's the Fall/Winter crop planting guide -- and parsnips are hardier than carrots.

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rainbowgardener
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The chart applestar linked to says that carrots will have a pretty good germination rate as long as temps are above 50. But if you look at the seed packet it says "plant as soon as the soil can be worked" which in my neck of the woods is well before when soil temp is above 50 or air temps are consistently above it. I usually plant my carrots very early. For me they do germinate that way but very s ... l...o....w...l...y. About the time I have given up on them and have started thinking about whether I should plant more or just put something different in the spot, they show up. They are very cold hardy.

JayPoc
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Thanks both of you. I'm used to seeing the "as soon as the ground can be worked" on carrots too, but this pack said "after all danger of frost" (which I thought was weird). I'll look at the links provided for the temp data.

JayPoc
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Still not sure about my last question in the first paragraph? If you had carrot seeds or seedlings outside in a container, how cold would it need to be for you to bring them inside? I doubt (hope) we'll get any more days in the single digits or teens...but I wouldn't be shocked if we have a few night where the lows could be around 20 or so....

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applestar
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I personally would NOT bring them inside. In any case, it's going to take like 3 weeks for them to sprout. By then the question may be moot?

IF you still get low 20's temp then, I would consider covering, but wouldn't bring inside.... AH! It just occurred to me why this is incongruous -- a container that you could consider BRINGING INSIDE is very likely to be too small for carrots unless you are talking 5 gal buckets.

Even short carrots like Danvers would need at least 8-10" depth I think. Round ball shaped carrots like Parisien Market, Tonda, Rondo.... could grow in 6"-8" depth, but I've decided I don't like them ...it feels too much like I'm being cheated when I find a nice diameter carrot top, pull and get a stubby little round ball of the same diameter. :roll:

JayPoc
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applestar wrote: a container that you could consider BRINGING INSIDE is very likely to be too small for carrots unless you are talking 5 gal buckets.
You guessed it. The carrots are in 5 gal buckets...the turnips are in something akin to a half whisky barrel.

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jal_ut
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Never have planted carrots in a container. Here I plant them directly in the garden early. Yes, they may be slow to come, but always do. Then when I see them I plant another row for a later batch.

They are cold hardy. I have never seen them quit because of a few cold nights down around 30.

You might want to try some direct seeded, and also plant those in the containers out. Have fun!

JayPoc
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jal_ut wrote: They are cold hardy. I have never seen them quit because of a few cold nights down around 30.
Yeah, my only concern is we've had temps in the negatives and single digits in the past couple of weeks, and it wouldn't be unheard of to see those kind of temps in the next few weeks. I'm guessing 10 degrees F would probably kill them, wouldn't you think? What about 15?
jal_ut wrote:Never have planted carrots in a container...You might want to try some direct seeded, and also plant those in the containers out. Have fun!
Not really an option. My soil is extremely rocky (more like, my rocks have some soil in them, in places). I live on top of a shale hill, and the places where I do have actual dirt it's fairly dense. Even so, I've tried in the past. Never got past the young seedling stage due to vicious attack slugs. If I was ever going to try carrots again, it had to be this way...deep, light soil, easier to keep out the slugs.

Peter1142
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Last year my fall sown carrots had no problems with nighttime temps around 18. They are very hardy. Getting them to germinate is another story.

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jal_ut
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Yes, they always take 3 weeks to germinate. I have never had them quit because of cool nights though.
They should grow OK in pots. Something deep enough.
Good luck.

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jal_ut
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Weird, got a double post out of that. (edit)

OK, will comment a bit about slugs. Here in this high dry desert climate, slugs are not a big problem.
We do see them at times when it is rainy and humid. Seems the sun and breeze sends them packing
as soon as the clouds move out.

You seem to have a greater problem? OK, everyone , chime in with your slug remedies.



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